Datasets:

olivierdehaene

/

xkcd

like 6

Mysteries

Mysteries

https://www.xkcd.com/1501

https://www.explainxkcd.com/wiki/index.php/1501:_Mysteries

[In a frame at the top left of the panel:] Mysteries [A chart with two crossing lines with double arrows. Each arrow is labeled:] X-axis left: Not that weird X-axis right: Weird as Hell Y-axis top: I have no explanation Y-axis bottom: Explanation seems pretty clear [In the chart there are 22 bullets. Each bullet is labeled. Below the labels are given from top to bottom in each of the four quadrants of the chart:] [Top left quadrant:] Who Carly Simon is singing about in You're So Vain UVB-76 Lindbergh baby Toynbee tiles Jimmy Hoffa [Top right quadrant:] MH370 Lead Masks Case DB Cooper The Wow signal Salish Sea feet Mary Celeste [Bottom left quadrant:] Voynich manuscript JFK Why I keep putting ice cream back in the fridge instead of the freezer Oak Island Money Pit [Bottom right quadrant:] Zodiac letters Amelia Earhart Lost Colony Kentucky meat shower Bigfoot Loch Ness Monster Dyatlov Pass incident

This comic shows a graph in which several "mysteries" are mentioned and placed on the graph according to how weird they are on the x-axis and the y-axis indicates whether Randall has an explanation or not for the mystery. Each item is listed in the table below . Items near the top-right corner (such as the MH 370 disappearance) are both mysterious and strange. Items near the bottom-left corner (such as Randall's absent-mindedness regarding ice cream) have a clear explanation and are not really strange either. Items near the top-left corner (such as the meaning of You're So Vain ) are mysterious but not really strange. Items near the bottom-right corner (such as the Dyatlov Pass incident ) have a clear explanation but are quite strange. The title text refers to the mystery of Randall staying up late to read Wikipedia articles, when he was already supposed to be asleep an hour ago. This is apparently not very unusual for him (see for instance 214: The Problem with Wikipedia ). And this mystery actually has an obvious explanation: Following up on an idea that eventually led to today's cartoon. Some of these mysteries have already been explored in xkcd. See 950: Mystery Solved where Randall "solves" Amelia Earhart, Lost Roanoke Colony, Jimmy Hoffa; 593: Voynich Manuscript ; and 1400: D.B. Cooper . Note that Randall uses similar diagrams in both 388: Fuck Grapefruit , 1242: Scary Names and 2466: In Your Classroom , which also contain different items. The first two also have an extra point, and the last two extra points mentioned in the title text. But all these points are in the title text because they are far off the chart, whereas in this comic it's the description of the point that is too long to fit on the chart. Extra info outside the chart is also used in the title text of 1785: Wifi , but this is a line graph. The X axis in the graph indicates weirdness. The table assumes that the item to the far left is 0% (not that weird) and the item to the far right is 100% (weird as hell). The Y axis indicates if Randall has an explanation. The table assumes that the item at the bottom is 100% (Randall has a clear explanation) and the item at the top is 0% (Randall has no explanation). [In a frame at the top left of the panel:] Mysteries [A chart with two crossing lines with double arrows. Each arrow is labeled:] X-axis left: Not that weird X-axis right: Weird as Hell Y-axis top: I have no explanation Y-axis bottom: Explanation seems pretty clear [In the chart there are 22 bullets. Each bullet is labeled. Below the labels are given from top to bottom in each of the four quadrants of the chart:] [Top left quadrant:] Who Carly Simon is singing about in You're So Vain UVB-76 Lindbergh baby Toynbee tiles Jimmy Hoffa [Top right quadrant:] MH370 Lead Masks Case DB Cooper The Wow signal Salish Sea feet Mary Celeste [Bottom left quadrant:] Voynich manuscript JFK Why I keep putting ice cream back in the fridge instead of the freezer Oak Island Money Pit [Bottom right quadrant:] Zodiac letters Amelia Earhart Lost Colony Kentucky meat shower Bigfoot Loch Ness Monster Dyatlov Pass incident

Wasted Time

Wasted Time

https://www.xkcd.com/1502

https://www.explainxkcd.com/wiki/index.php/1502:_Wasted_Time

[Cueball holding his smartphone in both hands is talking to White Hat.] Cueball: This new keyboard is like 30% faster! I'm never going back. [White hat replies and Cueball lifts his arms.] White Hat: Good, put those years of horror behind you. Cueball: C'mon. Sure, sometimes my focus on efficiency doesn't make sense. But we type a lot . [Cueball holding his smartphone in one hand while talking to White Hat.] Cueball: That 30% improvement pretty quickly adds up to a huge amount of wasted time rescued. [White hat replies and Cueball lifts one arm.] White Hat: I just watched you open Google News and then close it without reading it five times in a row. Cueball: The fact that I spend most of my time so stupidly only makes it more important not to waste any here.

In this comic, White Hat is pointing out to Cueball that his obsession with efficiency is inconsistent, something that is likely true of many people who claim to prize efficiency. Here, Cueball raves about his new mobile keyboard which allows him to type 30% faster than his old keyboard. He notes that people (presumably himself particularly) do a lot of mobile typing, and a 30% reduction in the time that takes would allow more time for other activities. White Hat, on the other hand, mocks Cueball for caring so much about mobile typing speed, suggesting that this may not be the first time Cueball has obsessed over minor improvements in efficiency. White Hat also notes that he's just seen Cueball open and close Google News five times without reading anything, providing an example of how Cueball's other actions do not embody the same commitment to efficiency that he claims to have. Cueball defends himself by saying that, since he wastes so much time, it's that much more important to improve efficiency in his life to make more time for important matters. The title text (presumably White Hat's reply) counters this defense by suggesting that Cueball may be better off using a slower keyboard, so that he will have less time to waste on stupid activities. This type of argument may be an example of a logical fallacy argument which suggests, perhaps incorrectly, that Cueball should spend less time doing stupid things to the extent that he spends longer doing things he already does. Interestingly, in this comic, White Hat appears as the voice of reason to Cueball, an inversion of their typical dynamic (see for instance 1386: People are Stupid and 1459: Documents ). The role-reversal may be an acknowledgment that while Cueball may often make a fool of White Hat, he's far from perfect himself. Randall 's misadventures in time management are a recurring topic (see 874: Time Management and the Time management category ). Mobile keyboard efficiency was previously tangentially referenced in 1068: Swiftkey , and Randall's habit of opening news sites only to quickly get bored or distracted was shown in 1411: Loop . [Cueball holding his smartphone in both hands is talking to White Hat.] Cueball: This new keyboard is like 30% faster! I'm never going back. [White hat replies and Cueball lifts his arms.] White Hat: Good, put those years of horror behind you. Cueball: C'mon. Sure, sometimes my focus on efficiency doesn't make sense. But we type a lot . [Cueball holding his smartphone in one hand while talking to White Hat.] Cueball: That 30% improvement pretty quickly adds up to a huge amount of wasted time rescued. [White hat replies and Cueball lifts one arm.] White Hat: I just watched you open Google News and then close it without reading it five times in a row. Cueball: The fact that I spend most of my time so stupidly only makes it more important not to waste any here.

Squirrel Plan

Squirrel Plan

https://www.xkcd.com/1503

https://www.explainxkcd.com/wiki/index.php/1503:_Squirrel_Plan

[There are three squirrels. One is suspended from a balloon. The other two are sitting on the ground, looking up at it.] Squirrel to the right: Once you've chewed a hole in the Sun, shoot the balloon to fall back to earth, then pull the parachute ripcord to land. Squirrel tied to balloon: Are you sure it's full of acorns? Squirrel to the right: Look how bright and magnificent it is! What else could be in there?

These particular squirrels are ambitious but misguided, like the characters in the myth of Icarus and Daedalus (it should be noted that Randall does not see it that way, as seen in the bottom of "Interplanetary Cessna" ), or the Tower of Babel . The squirrels' understanding of astrophysics is lacking, regarding the distance to the sun and appropriate transportation to reach it in addition to the need to resist the sun's heat and exist in the vacuum of space. Their belief that the sun is made of acorns reflects their uniquely acorn-focused worldview, a reference to the tendency of real-life squirrels to gather and store acorns as winter food, as well as their single-minded dedication to overcoming obstacles (even elaborately-constructed obstacle courses ) for the sake of obtaining nuts. The title text reveals that "halfway to the sun," 75 million kilometers from all known acorns in our universe, the airborne squirrel seems to jeopardize the entire mission because he wants to test if the balloon itself is full of acorns. Basic observational skills will tell anyone that acorns do not float [ citation needed ] , but the idea follows the logic stated by the squirrels: If the sun, being so magnificent, must be full of acorns, then a balloon powerful enough to take a squirrel to the sun must also be powered by something amazing, like acorns. Obviously, neither the sun or balloons are filled with acorns [ citation needed ] . Usage of balloons for space travel is a prominent motif in early science fiction; see, for example, " The Unparalleled Adventure of One Hans Pfaall " by Edgar Allan Poe. [There are three squirrels. One is suspended from a balloon. The other two are sitting on the ground, looking up at it.] Squirrel to the right: Once you've chewed a hole in the Sun, shoot the balloon to fall back to earth, then pull the parachute ripcord to land. Squirrel tied to balloon: Are you sure it's full of acorns? Squirrel to the right: Look how bright and magnificent it is! What else could be in there?

Opportunity

Opportunity

https://www.xkcd.com/1504

https://www.explainxkcd.com/wiki/index.php/1504:_Opportunity

[The year (or year and first sentence) for each panel is written in a small frame at the top of each panel. It breaks the top frame of the panels.] [Ponytail is sitting at a computer, facing left. Hairbun stands behind her.] 2010: Ponytail: After six years, Spirit is down, but Opportunity is still going strong. Hairbun: Tough little rover! [Opportunity traveling on Mars. Text is written in frames with zigzag lines] 2015: Off-screen: Eleven years, wow. Off-screen 2: Wasn't the original mission 90 days? Off-screen: This is starting to get weird. [Cueball and Megan sitting at a computer, facing right.] 2023: Cueball: The battery is totally disconnected. How can it still be moving?? Megan: Given what it did to the Mars 2020 rover, we may never know. [Two Martian inhabitants looking like Cueball and Megan stands on a cliff edge pointing towards a dark, mountainous region. Behind them are a tower and a hover car] 2450, terraformed Mars, Martian imperial capital: Martian Cueball: Everything the light touches is our kingdom. Martian Megan: What's that dark area? Martian Cueball: That is Opportunity's half of the planet. We must never go there.

This comic is talking about the robotic science platform Opportunity . On January 25, 2004, the Opportunity rover landed on the surface of Mars for the purpose of gathering data about the surface of Mars. Opportunity has proven remarkably robust, and the comic extrapolates the rover's resilience to absurdity for comedic effect. As of Feb 12th, 2019, the Opportunity rover has finally been declared dead after 5352 Sols (Mars Days) or 5500 Earth days on Mars. On Feb 13th, 2019, Randall eulogies the Opportunity Rover in 2111: Opportunity Rover . The comic depicts the two scientists Ponytail and Hairbun at ground control being amazed at this fact already in 2010, and (maybe the same two) scientists continue to discuss this in 2015 in the second panel. They mention another Martian rover, Spirit that was also sent to Mars on the same date as Opportunity. Unfortunately, it became stuck and a sandstorm covered its solar panels. On March 22, 2010, it was thought that Spirit's batteries finally ran out, marking the end of its mission. This was covered in 695: Spirit , in which the Spirit rover is also portrayed with an anthropomorphic personality. In 2023, Opportunity is still moving despite having supposedly no power source. It also became aggressive and deactivated the Perseverance rover sent in 2020 . Cueball and Megan can't explain how it moves, but investigating is now too dangerous. This evolution is similar to the stories of HAL 9000 (from 2001: A Space Odyssey ) and V'Ger (from Star Trek: The Motion Picture ), both of which became dangerous to human beings. By 2450, humans have colonized and terraformed Mars. Maybe it is the 2023 Cueball and Megan's descendants that are looking out over their huge "kingdom" from the capital on Mars. However Opportunity is by now dominating half of the planet and will not allow humans to enter its dark reign. "Everything the light touches" is a reference to a line by Mufasa in The Lion King . Mufasa's son Simba then asks "What about that shadowy place?" and Mufasa tells him "That is beyond our borders. You must never go there". This was used again in 1608: Hoverboard , where Cueball tells the same line to Ponytail in the left part of the world. In " what if " "Sunset on the British Empire" , concerning the end of the sun shining on the British Empire, Cueball tells a child that everything the light touches is their kingdom, and the child asks (in the title text) "What about that shadowy place over there?" to which Cueball replies (also in the title text), "That's France. We'll get it one of these days." The title text forecasts the first words of the first astronauts on the surface of Mars. At first, the astronaut copies the first words of Neil Armstrong on the Moon ("That's one small step for [a] man, one giant leap for mankind") but it is interrupted by the Opportunity rover. Opportunity has a drill to collect Martian rock samples, but here it is heavily suggested that the drill is being used as a weapon against the astronaut. [The year (or year and first sentence) for each panel is written in a small frame at the top of each panel. It breaks the top frame of the panels.] [Ponytail is sitting at a computer, facing left. Hairbun stands behind her.] 2010: Ponytail: After six years, Spirit is down, but Opportunity is still going strong. Hairbun: Tough little rover! [Opportunity traveling on Mars. Text is written in frames with zigzag lines] 2015: Off-screen: Eleven years, wow. Off-screen 2: Wasn't the original mission 90 days? Off-screen: This is starting to get weird. [Cueball and Megan sitting at a computer, facing right.] 2023: Cueball: The battery is totally disconnected. How can it still be moving?? Megan: Given what it did to the Mars 2020 rover, we may never know. [Two Martian inhabitants looking like Cueball and Megan stands on a cliff edge pointing towards a dark, mountainous region. Behind them are a tower and a hover car] 2450, terraformed Mars, Martian imperial capital: Martian Cueball: Everything the light touches is our kingdom. Martian Megan: What's that dark area? Martian Cueball: That is Opportunity's half of the planet. We must never go there.

Ontological Argument

Ontological Argument

https://www.xkcd.com/1505

https://www.explainxkcd.com/wiki/index.php/1505:_Ontological_Argument

[Megan and Cueball are walking side-by-side.] Megan: ...but wouldn't a God who could find a flaw in the ontological argument be even greater?

Ontology is the study of being , reality , and existence . “The ontological argument ” is an attempt at proving the existence of God through reasoning about the nature of “being”. Megan 's statement in the comic is likely a reference to what is considered the first ontological argument, that of 11th Century philosopher Anselm of Canterbury . His argument starts by defining God as “that than which nothing greater can be conceived ”. Another step in the argument is that you can conceive of such a being even if you don't believe it exists. Yet another step is the statement that a being, of which one can conceive, and which exists, is certainly greater than a being of which one can conceive and which does not exist. Implicit in the argument are two essential premises, both of which are controversial. These are a) that the existence of such a being is possible, and b) that existence is a great-making quality. The comic makes fun of Anselm's ontological argument by extending to absurdity the claim that a being who exists is greater than one who does not exist, and that therefore God must exist. A God who can disprove the ontological argument must be greater than one who cannot disprove the ontological argument, therefore the ontological argument proves the existence of a God that disproves it. This argument, though a joke, carries some weight. If Anselm's argument is sound, then disproving it is impossible, and God cannot do it. But if doing things is a great-making quality (a common assumption), then surely doing impossible things would be an even stronger great-making quality. Therefore the argument is able to be disproven, albeit only by God, which contradicts the initial premise that the argument is sound. Therefore, either doing things is not great-making, or the entire ontological argument is invalid reasoning. The title text carries the absurdity a step further. The comic also may be drawing an analogy to the omnipotence paradox , as it also refers to the idea that God's power would be greater if He could do the logically impossible. If Randall believes that Anselm's ontological argument is logically sound and based on true premises, then he should think it is impossible to disprove. Therefore, he references the omnipotence paradox by requiring that God do such an impossible thing in order to have maximally great power. A popular parody of the ontological argument is that of Richard Dawkins , in his best-selling book “ The God Delusion ”. His parody is a version of the argument which attempts to prove that God does not exist. It is similar in approach to this comic and to the omnipotence paradox, in that it also requires a God that can do the logically impossible. In Dawkins' version— borrowed from the Australian philosopher Douglas Gasking —God's greatness is demonstrated by his creation of the world. A being that somehow overcomes the great handicap of not existing and goes on to create the world would certainly be greater than a being that exists and creates the world. Therefore God, who by definition is “that than which nothing greater can be conceived”, must not exist. Another, rather more famous parody, but which is entirely unrelated to the comic in approach, is that of Gaunilo of Marmoutiers , in which he argues for the existence of a maximally great island. This parody, added to the comic, seems to tell us what happened to the legendary Atlantis . It is worth noting that Anselm himself rebutted Gaunilo's argument, claiming that it was based on a fundamental misunderstanding of Anselm's original argument. Not all ontological arguments for the existence of God rely on the notion that a God that exists is greater than one that does not exist. Examples include the modal ontological argument from Alvin Plantinga , and Gödel's ontological proof . Graham Oppy , an authority on ontological arguments, attempts to classify here what exactly makes arguments ontological; he concludes that it is that they are a priori in nature. He also classifies them into eight categories: definitional , conceptual, modal, Meinongian , experiential , mereological , higher order, and Hegelian . This comic, in particular in the way Megan and Cueball are walking and in its reference to theology, greatly resembles the earlier comic 1315: Questions for God . [Megan and Cueball are walking side-by-side.] Megan: ...but wouldn't a God who could find a flaw in the ontological argument be even greater?

xkcloud

xkcloud

https://www.xkcd.com/1506

https://www.explainxkcd.com/wiki/index.php/1506:_xkcloud

[This transcript only transcribes what can be seen in the first picture shown at the top of the explanation here. For more see link below.] [One large frame with a five part comic and a large red button at the bottom.] [Cueball sitting behind a desk.] Cueball: We've made a huge mistake. Desk: XKCD.COM [Cueball stands and indicates a motley collection of computers and related equipment strewn around the desk.] Cueball: I figured starting a cloud services company would be easy. Cueball: After all, I've got tons of computers! [A zoomed view on Cueballs head.] Cueball: Facebook, Twitter, Tumblr— they all struggle to protect privacy and user data... Cueball: And we offered a solution. Cueball: I forget what it was, though. [Cueball is standing with his arms up.] Cueball: Anyway, long story short, we screwed up immediately and lost tons of their data. Cueball: Also a bunch of stuff is literally on fire? [Cueball standing behind a desk.] Cueball: We can fix this. Cueball: But we need your help. Desk: XKCD.COM [Below the above is a large red rectangular clickable button, that will take the reader on to the interactive part of the comic. On the button it says in large white letters:] CLICK HERE To help us recover user data before Facebook & Co notice we lost it. [The standard text for the next possible pages can be seen on the link to the continued transcript . Also here will be a list (which may not be possible to make complete) with possible text for the lost data.]

This was the sixth April fools' comic released by Randall . The previous fools comic was 1350: Lorenz from Tuesday April 1st 2014. The next was 1663: Garden scheduled for release Friday April 1st 2016, but in the end released on Monday April 4th 2016. In this interactive April Fools' Day comic Cueball , presumably representing Randall , admits to the readers he built a flimsy cloud services company using spare computers and parts. Included in the cloud hardware are (from left to right) a Macintosh , several old laptops, an Alienware tower, a Nintendo VirtualBoy , an old desktop with the cover off, and an Atari Pong Console . He named the company after xkcd, xkcloud being a portmanteau of " xkcd " and " cloud ", here pronounced XK-cloud. The portmanteau incidentally still contains all four xkcd letters in the correct order: xkcLOUd. This was later reused for the xkcd keyboard in 2150: XKeyboarCD , where the word Keyboard, has an X before the word and a C before the D with the xkcd letters capitalized. After providing his services to various (very big) companies ( Facebook , Twitter and Tumblr ), that are very concerned with securing the users data, his setup failed (some portions may even have caught fire? He is not sure). This has caused him to lose the data he was required to preserve as part of his service. He thus requests the readers help to make up and re-imagine the lost data by pressing the large red button at the bottom of the comic. Preferably before Facebook & Co notice we lost it. If you take him up on his request and push the button, you will be taken to a "survey" where you will get the chance to help by either trying to combine a posted picture with its lost text or, vice versa, by trying to combine a posted text with its lost picture. In either case you get a selection of texts/pictures to choose from but can also choose to write your own text or even draw the picture. After doing this you get to see this combination in the news feed together with several other posts (which other people have helped combine from other lost data). And then you can continue helping as long as you like. The content of the "surveys" appear to come from reader submissions, and are different upon every click. This is thus both an interactive and a dynamic comic with only the first picture shown on top of this page. By inviting the xkcd readers to add content that will be displayed in the comic later, the result of all the interactions leads to the generation of crowd-sourced content . It was not immediately clear if the reader-created drawings or captions are, in fact, being cycled into the surveys and feeds, or if the displayed items were all created by Randall and the reader-created content is simply discarded. With the huge amount of different comments and drawings that already appeared on the first day, and since especially the drawings look like they are created in the simple Paint app (i.e. not by Randall), there can be no doubt that most of the content is created by the users. However he must have made some pictures to get it all started, and at least one of these can be seen here . This comic resembles last years April Fools' comic 1350: Lorenz where user input also generated a very complex crowd-sourced comic. In both comics it was possible to create a permalink to save a given version of the comic to share with others. An earlier comic was also related to problems with cloud computing: 908: The Cloud . Due to the very complex nature of this comic, there are lots of details that may need an explanation. This can be found in the sections below. On every of the pages after the front page Cueball sits at his desk labeled XKCD.COM Below him are xkcloud's policy: Our policy regarding your personal data : As can be seen he is getting desperate because people keep sending them more data. He has no place to store it. And he do not even know who the data belongs to. So now he hopes someone else recognize the data (what you are doing if you choose to help). In the end he simply pleads for people to stop and then shouts Help . If you click on the desk you are sent back to the front page of the comic. But below Help is their real contact detail Don't contact us : We are open for anyone to chat here. Hey you! Come right over and say hello to us! ~ euphoria.io/room/xkcd [This transcript only transcribes what can be seen in the first picture shown at the top of the explanation here. For more see link below.] [One large frame with a five part comic and a large red button at the bottom.] [Cueball sitting behind a desk.] Cueball: We've made a huge mistake. Desk: XKCD.COM [Cueball stands and indicates a motley collection of computers and related equipment strewn around the desk.] Cueball: I figured starting a cloud services company would be easy. Cueball: After all, I've got tons of computers! [A zoomed view on Cueballs head.] Cueball: Facebook, Twitter, Tumblr— they all struggle to protect privacy and user data... Cueball: And we offered a solution. Cueball: I forget what it was, though. [Cueball is standing with his arms up.] Cueball: Anyway, long story short, we screwed up immediately and lost tons of their data. Cueball: Also a bunch of stuff is literally on fire? [Cueball standing behind a desk.] Cueball: We can fix this. Cueball: But we need your help. Desk: XKCD.COM [Below the above is a large red rectangular clickable button, that will take the reader on to the interactive part of the comic. On the button it says in large white letters:] CLICK HERE To help us recover user data before Facebook & Co notice we lost it. [The standard text for the next possible pages can be seen on the link to the continued transcript . Also here will be a list (which may not be possible to make complete) with possible text for the lost data.]

Metaball

Metaball

https://www.xkcd.com/1507

https://www.explainxkcd.com/wiki/index.php/1507:_Metaball

[Megan runs towards a bouncing soccer football.] [Megan kicks the soccer football upwards.] [Cueball leaps towards the ball as it falls towards a basketball hoop. Hairbun also stretches her arm up.] Ponytail (offscreen): Out! [Ponytail walks toward them consulting a piece of paper divided in sections:] [Megan (offscreen):] What do you mean , out?! Ponytail: The ball clipped the corner of the baseball zone. Infield fly rule. [Megan (offscreen):] Aw, maaan ...

In the first two panels of this game Megan kicks a football (also known as a soccer ball in some regions), but the surprise comes in the next panel when it turns out she tried to kick it into a basketball hoop where Cueball is either trying to catch, stop or dunk the ball. Hairbun is also reaching an arm up after the ball. But then Ponytail yells " Out! ". When Megan asks Ponytail why the ball is out, Ponytail explains it is due to the infield fly rule that was invoked when the ball crossed into the baseball zone - a very complicated rule to understand for baseball outsiders. They are playing a ball game that incorporates the rules of many games that use a ball . The rules seem to be based on the location of the ball . Ponytail is holding a map which divides the area into zones. Each time the ball enters a new zone, the rules change to become the rules of the ball game represented in that zone. The name "Metaball" is the combination of the prefix " meta " and the word " ball ". Not long before this comic there was another comic with "meta" in the title: 1447: Meta-Analysis . The entire joke is meta in 917: Hofstadter . Megan is out according to the rules of baseball, because the football that she initially kicked in the football zone in an attempt to score in the basketball hoop (in the basketball zone), clipped the corner of the baseball zone. And suddenly her high kick turned into a pop fly and Ponytail (presumably the referee (and creator/ruler) of this game) invoked the infield fly rule which forces the batter out. In this case that would be the kicker Megan as she is the last to have touched the ball. In baseball the infield fly rule can be invoked by the umpire (i.e. the referee in baseball, Ponytail in this case), to prevent an infielder from intentionally dropping a fair ball when runners are on multiple bases, forcing the runners on base to advance and allowing the infielder's team to quickly perform a double or triple play by throwing the ball to where the runners are trying to get and performing force out on their base. The infield fly rule, once called out by the umpire, forces the batter to be out whether or not the infielder tries to get the batter out. While complicated, and difficult for outsider to understand, the rule has been in baseball for a long time and makes sense in context. The title text continues the comic. After Megan is ruled out, even though Cueball misses the catch, the ball now enters the golf section of the field, meaning that the players would have to hit the ball into a golf hole to score. Given that the ball is much larger than a standard golf ball, this would prove difficult. However, before they get this far, the situation changes as the ball rolls into a separate section of the field called the ice hazard. On a golf course a hazard is either a bunker (with sand) or a water hazard . If the latter type freezes over it could be called an ice hazard. However, in this Metaball game this section of the course is apparently used to play some form of ice hockey . And since the game has been held up when Megan was called out, they will now have to restart the game with a face-off (a skirmish between two players of opposing teams to restart the game). It can be argued that an ice hockey puck can be considered a ball, since ice hockey has evolved from, and is a variation of, older stick-and-ball games. And since they play both baseball, basketball and golf with the association football, they could also continue playing ice hockey with this ball instead of a puck. For the record there are several other versions of hockey that are played with a ball ( ball hockey for instance) and at least one of these is played on ice (see broomball ). In these games face-offs are also used. It seems likely that Randall has chosen some of the most popular sports of the US - and then used a soccer/football instead of an American football . Given the timing of this comic with the US collegiate basketball tournament , we may assume Randall is writing as a response to that. He has previously given an opinion on sports (see for instance 904: Sports , 1107: Sports Cheat Sheet and 1480: Super Bowl ). This concept is very similar to Calvinball from the comic strip Calvin and Hobbes by American cartoonist Bill Watterson . [Megan runs towards a bouncing soccer football.] [Megan kicks the soccer football upwards.] [Cueball leaps towards the ball as it falls towards a basketball hoop. Hairbun also stretches her arm up.] Ponytail (offscreen): Out! [Ponytail walks toward them consulting a piece of paper divided in sections:] [Megan (offscreen):] What do you mean , out?! Ponytail: The ball clipped the corner of the baseball zone. Infield fly rule. [Megan (offscreen):] Aw, maaan ...

Operating Systems

Operating Systems

https://www.xkcd.com/1508

https://www.explainxkcd.com/wiki/index.php/1508:_Operating_Systems

[All text is in capitals. At the top of the panel:] Operating Systems running in my house [At the bottom there is time-line that runs from 1990 to 2066. It has small indicators for every year, larger for every 5 years and largest for every 10 years. Below the 10 year indicators are written the years. Also the year 2015 is marked:] 1990 2000 2010 Now 2020 2030 2040 2050 2060 [Bars above the time-line in four levels are labeled with operating system names, representing the time period for that OS. Below is a list of the bars on the time-line in order of first appearance (with approximate year ranges given). Also the level from 1-4 is indicated, with level 1 just above the time-line and level 4 the highest level above the line:] [Level 1 from 1988 to 1998 (extends a little left past the beginning of the time-line but not off panel):] MS DOS [Level 2 from 1993 to 2007:] Windows [Level 3 from 1994 to 2001:] Mac OS [Level 1 from 1999 to 2018:] Linux [Level 2 from 2009 to 2023. On the way the bar merges with iOS around 2018 thru 2022:] OS X [Level 3 from 2009 to 2016:] Android [Level 4 from 2013 to 2022. On the way to 2022 the bar moves down past Android to merge with OS X after 2018:] iOS [Level 1 from 2018 to 2028. The text is written in square brackets:] [Something].js [Level 3 from 2022 to 2029:] TinderOS [Level 2 from 2023 to 2032:] Nest [Level 1 from 2028 to 2041:] Elon Musk Project: [Level 3 from 2030 to 2036:] DOS, but ironically [Level 2 from 2034 to 2041:] Blood Drone [This is not a bar, but the text (in three lines) is in a double bar-height (level 1-2) square bracket. The bracket extends from 2042 to 2051:] [Human civilization ends in fire] [Level 1 from 2059 going past the end of the panel past 2066:] GNU/Hurd

In this comic, Randall gives an overview of the past, present and (speculatively) future of the operating systems running in his house at any given time. Notably, because Randall is fascinated by technology, he has had more than one OS running in his household since the mid '90's. The timeline tracks how Operating Systems have come and gone over the years, and the gradual shift from desktop Operating Systems to mobile can be observed. Beyond the present day, we see some of Randall's humorous predictions as to which technologies and companies will dominate the Operating System landscape in the future. It may be that the OS that is closest to the time-line is also the one he mainly uses during these extended periods. Previous and current systems: His predictions for the future include: The title text refers to Richard Stallman , the founder of the Free Software movement and the GNU and Hurd projects. A survivor of the fire that ended the human civilization has uncovered a slightly burned ( singed ) picture of him. Those gathered can see, either directly from the picture or because they already know of Stallman, that this was a man that really believed in something. In this case it was free software . Inspired by his image, they rebuild their lost civilization and finish Hurd development. The GNU/Hurd reference might also be a pun, as in a "herd" of Gnus "running" in his living room, as wild animals reclaim the Earth after the end of human civilization. GNU is a collection of free software utilities, particularly the system utilities used with the Linux Kernel to form the Linux operating system (often called GNU/Linux by those who wish to emphasize the contribution of the GNU project). Hurd is an operating system kernel designed as part of GNU project that could be used in place of the Linux kernel to produce a complete GNU operating system. Hurd has a microkernel architecture, which has many perceived advantages over Linux's monolithic kernel, and is thought by many to be technically superior, despite its low adoption rate compared to the Linux kernel. Randall has made several comics about free software and also about Stallman. See this list of comics featuring Richard Stallman . Most of these are also about free software in some form. [All text is in capitals. At the top of the panel:] Operating Systems running in my house [At the bottom there is time-line that runs from 1990 to 2066. It has small indicators for every year, larger for every 5 years and largest for every 10 years. Below the 10 year indicators are written the years. Also the year 2015 is marked:] 1990 2000 2010 Now 2020 2030 2040 2050 2060 [Bars above the time-line in four levels are labeled with operating system names, representing the time period for that OS. Below is a list of the bars on the time-line in order of first appearance (with approximate year ranges given). Also the level from 1-4 is indicated, with level 1 just above the time-line and level 4 the highest level above the line:] [Level 1 from 1988 to 1998 (extends a little left past the beginning of the time-line but not off panel):] MS DOS [Level 2 from 1993 to 2007:] Windows [Level 3 from 1994 to 2001:] Mac OS [Level 1 from 1999 to 2018:] Linux [Level 2 from 2009 to 2023. On the way the bar merges with iOS around 2018 thru 2022:] OS X [Level 3 from 2009 to 2016:] Android [Level 4 from 2013 to 2022. On the way to 2022 the bar moves down past Android to merge with OS X after 2018:] iOS [Level 1 from 2018 to 2028. The text is written in square brackets:] [Something].js [Level 3 from 2022 to 2029:] TinderOS [Level 2 from 2023 to 2032:] Nest [Level 1 from 2028 to 2041:] Elon Musk Project: [Level 3 from 2030 to 2036:] DOS, but ironically [Level 2 from 2034 to 2041:] Blood Drone [This is not a bar, but the text (in three lines) is in a double bar-height (level 1-2) square bracket. The bracket extends from 2042 to 2051:] [Human civilization ends in fire] [Level 1 from 2059 going past the end of the panel past 2066:] GNU/Hurd

Scenery Cheat Sheet

Scenery Cheat Sheet

https://www.xkcd.com/1509

https://www.explainxkcd.com/wiki/index.php/1509:_Scenery_Cheat_Sheet

[Above the frame is the following text.] A cheat sheet for figuring out where in the US you are by recognizing the background from movies (for use by GeoGuessr players and crash-landed astronauts) [In the frame is a map of the mainland USA with the 48 mainland states lined out in thin gray lines. All areas on the map have been enclosed in sections divided by curved black lines. These sections sizes goes from encompassing several states down to just a small section of a single state. The sections cover the entire USA without any holes. There is also one section in the Atlantic Ocean. All sections are labeled. If the section is large enough the text stands inside, if it is too small, the text is outside and an arrow will point to the relevant section [Here below all the text on the map (mainly film titles) will be transcribed from top to bottom and (when possible) by going through the columns that seems to appear in the sections when going from left to right. The State Postal Codes will be used when referring to the states covered by each section] [Small section covering the west coast around the state border between WA and OR, which is surrounded on three sides by the next section mentioned below. It is labeled with an arrow:] The Goonies [Large section covering WA, OR and top of CA. The section has two titles, with the second one standing with smaller font below the first:] Twilight 50 Shades of Grey [Small section around San Francisco, CA:] Zodiac [Very tiny section covering only Alcatraz off the coast of San Francisco, CA. It lies inside section mentioned above. It is labeled with an arrow:] The Rock [Large section covering most of MT as well as part of WY, SD and NE. The section has two titles:] Dances with Wolves Starship Troopers [Medium section covering most of ID and part of MT:] Napoleon Dynamite [Medium section covering part of OR, ID, NV and UT:] The Sandlot [Medium section mainly covering the top part of NV:] Wild Wild West [Medium section covering most of NV and small part of CA. The section has two titles, with the second one standing with smaller font below the first plus description:] Top Gun & the part of Independence Day where Will Smith crashes [Small section covering central CA:] That movie about wine & talking [Medium section covering a large part of the southern part of CA around Hollywood, Los Angeles:] Every movie with a big budget, explosions or someone who says "cool!" [Medium section covering half of WY and small parts of UT and CO:] Brokeback Mountain [Medium section covering part of WY, CO and NE. The part in parenthesis in a smaller font:] Oregon Trail (the only part I ever got to) [Large section covering small part of UT and the half bottom of UT and CO and top half of AZ and NM:] Roadrunner cartoons [Medium section covering a small part of the southern CA and small part of AZ. The part beneath the title in a smaller font:] The Truman Show, but with desert as the background [Small part at the bottom of AZ. The section has two titles:] Tombstone & The Mask of Zorro [Large section covering the a small part of AZ, the bottom half of NM as well as a third of TX:] No Country for Old Men [Large section covering all of ND, most of MN, half of SD and a small part of MT:] Fargo [Medium section covering most of NE and small parts of MN and IA. The section has three titles. The top two are marked with a square bracket to the left. The text of this given before the third title:] Interstellar Star Trek (2009) ] Earth parts Field of Dreams [Medium section covering large parts of IA, MO and IL:] The Music Man [Medium section covering mainly KS, but also a small part of Co and OK:] The Wizard of Oz [Medium section covering most of OK and small part of MO and AR:] Twister [Medium section covering the top part of TX and small parts of OK and AR:] True Grit [Large section covering a third of TX (the eastern part all the way down) and small parts of AR and LA. The section has three titles:] Office Space Dazed and Confused Kill Bill [Small section around and below Chicago, IL, which is surrounded on three sides by the next large section mentioned below. It is labeled with an arrow:] Blues Brothers [Very small section almost a circle centered around Detroit, MI completely inside the section here below. It is labeled with an arrow:] 8 Mile [Large section covering all of WI, MI, IN and OH as well as parts of IL and KY. That is except for the two small sections described above, which are inlaid in this one. There are two items in this section. The one below is in smaller font:] A Christmas Story &That song about Jack and Diane [Medium section covering half of AR, small parts of IL and MO as well as bits of KY, TN and MS:] Anything by Mark Twain [Medium section covering half of TN and part of KY:] Walk the Line [Large section covering all of AL most of MS and half of GA. There are two titles in this section:] Big Fish O Brother Where Art Thou [Small section covering top of LA and small part of MS:] Duck Dynasty [Medium section covering the bottom half of LA and the very bottom of MS. There is a very small section at the bottom of LA that are not included in this but in the next. There are two titles in this section:] Princess and the Frog All Dogs go to Heaven [Small section covering the very eastern end of the bottom of LA – maybe including New Orleans. It is labeled with an arrow:] Beasts of the Southern Wild [Medium section covering half of PA and western part NY:] Groundhog Day [Small section covering the middle part of VA as well as small parts of PA, MD and WV:] Dirty Dancing [Medium section covering most of WV, half of TN, a small parts of KY as well as tiny bits of VA, NC and GA:] October Sky [Large section covering all of SC, most of NC as well as half of VA and GA. There are two titles in this section:] Gone with the Wind Forrest Gump [Large section covering most of FL except the bottom part which are covered by the next two sections:] The Truman Show [Small section covering the very bottom of FL except the east coast. It is labeled with an arrow:] Adaptation [Small section covering the very bottom the east coast of FL. It is labeled with an arrow:] Miami Vice [Small section covering most of the top of VT and a small part of NY. It is labeled with an arrow:] Super Troopers [Small section covering the central part of NY.] My Side of the Mountain (book) [Small section covering the eastern part of NY, western part of MA, top part of CT as well as bits of VT and RI.:] War of the Worlds (2005) [Small section covering the eastern part of PA and small bits of NY and MD. There are two titles in this section:] Signs & The Village [Medium section covering several large cities of the east coast including New York City, Philadelphia and Washington, DC. It covers most of DE and NJ and large parts of MD (with DC) and the bit of NY with the city. The text is not a title and the it is written in square brackets…:] [Generic city] [Small section covering the east coast along VA and NC, but also with small bits of MD and DE at the top:] Deep Impact [Medium section covering all of ME, the top tip of NH and eastern top of VT:] Pet Semetary [Small section covering the most of the bottom parts of NH and VT:] What about Bob [Very small section surrounding Boston in MA. It is labeled with an arrow:] The Departed [Small section covering the east coast along MA, RI, CT and NJ:] Jaws [Large section off the east coast in the Atlantic Ocean:] The Hunt for Red October

In this comic Randall jokes that large areas of the continental (mainland) United States can be characterized by the locations of a single movie. Especially in the Midwest, there are several very large areas that he describes with just one film. The map is the most detailed in the northeast , which is where Randall lives. The map is divided into the 48 states of the mainland by thin gray lines. On top of these are drawn black lines that divide the map into 50 sections. (A 51st section is located in the Atlantic Ocean.) Inside each section is at least one reference that is supposed to describe the entire area encompassed by the section. In most cases it is the title of a movie (or two to three titles), but it could also be more general specter of movies (all movies with a big budget, or those with whose title is an east coast city name) or it could even be a book/song that describes the relevant area. The map's heading describes the idea behind it; if you know this and the relevant movies, you can use it to determine where you are by comparing your knowledge of the movies with the scenery you can see from where you stand. Below the heading, the two groups of people who will get the most use out of this sheet are listed. The first is "GeoGuessrs". GeoGuessr is a game using Google Street View images, which drops the player in a random location and challenges them to work out where they are. (It was previously referenced in 1214: Geoguessr ). The second group is "crash-landed astronauts". Obviously, if you've just crash-landed on Earth, knowing your location would be very helpful. Some entries (for instance, Groundhog Day ) reflect the locations where the stories are set, and others (like Dances with Wolves ) reflect where they were filmed. Others are even more detached, as it is the sceneries from the movie that resembles a given place, even though it is neither filmed there or takes place there. It could also be a cartoon, which is of course only set in an imaginary world that may resemble the real world. The title text references Anton Chigurh (portrayed by Javier Bardem ), who is the main antagonist of the film No Country For Old Men . In this case he would have taken over the role of Wile E. Coyote , and would thus hunt down The Road Runner at the boundary between the sections for these two movies, which would be somewhere in the New Mexico desert. [Above the frame is the following text.] A cheat sheet for figuring out where in the US you are by recognizing the background from movies (for use by GeoGuessr players and crash-landed astronauts) [In the frame is a map of the mainland USA with the 48 mainland states lined out in thin gray lines. All areas on the map have been enclosed in sections divided by curved black lines. These sections sizes goes from encompassing several states down to just a small section of a single state. The sections cover the entire USA without any holes. There is also one section in the Atlantic Ocean. All sections are labeled. If the section is large enough the text stands inside, if it is too small, the text is outside and an arrow will point to the relevant section [Here below all the text on the map (mainly film titles) will be transcribed from top to bottom and (when possible) by going through the columns that seems to appear in the sections when going from left to right. The State Postal Codes will be used when referring to the states covered by each section] [Small section covering the west coast around the state border between WA and OR, which is surrounded on three sides by the next section mentioned below. It is labeled with an arrow:] The Goonies [Large section covering WA, OR and top of CA. The section has two titles, with the second one standing with smaller font below the first:] Twilight 50 Shades of Grey [Small section around San Francisco, CA:] Zodiac [Very tiny section covering only Alcatraz off the coast of San Francisco, CA. It lies inside section mentioned above. It is labeled with an arrow:] The Rock [Large section covering most of MT as well as part of WY, SD and NE. The section has two titles:] Dances with Wolves Starship Troopers [Medium section covering most of ID and part of MT:] Napoleon Dynamite [Medium section covering part of OR, ID, NV and UT:] The Sandlot [Medium section mainly covering the top part of NV:] Wild Wild West [Medium section covering most of NV and small part of CA. The section has two titles, with the second one standing with smaller font below the first plus description:] Top Gun & the part of Independence Day where Will Smith crashes [Small section covering central CA:] That movie about wine & talking [Medium section covering a large part of the southern part of CA around Hollywood, Los Angeles:] Every movie with a big budget, explosions or someone who says "cool!" [Medium section covering half of WY and small parts of UT and CO:] Brokeback Mountain [Medium section covering part of WY, CO and NE. The part in parenthesis in a smaller font:] Oregon Trail (the only part I ever got to) [Large section covering small part of UT and the half bottom of UT and CO and top half of AZ and NM:] Roadrunner cartoons [Medium section covering a small part of the southern CA and small part of AZ. The part beneath the title in a smaller font:] The Truman Show, but with desert as the background [Small part at the bottom of AZ. The section has two titles:] Tombstone & The Mask of Zorro [Large section covering the a small part of AZ, the bottom half of NM as well as a third of TX:] No Country for Old Men [Large section covering all of ND, most of MN, half of SD and a small part of MT:] Fargo [Medium section covering most of NE and small parts of MN and IA. The section has three titles. The top two are marked with a square bracket to the left. The text of this given before the third title:] Interstellar Star Trek (2009) ] Earth parts Field of Dreams [Medium section covering large parts of IA, MO and IL:] The Music Man [Medium section covering mainly KS, but also a small part of Co and OK:] The Wizard of Oz [Medium section covering most of OK and small part of MO and AR:] Twister [Medium section covering the top part of TX and small parts of OK and AR:] True Grit [Large section covering a third of TX (the eastern part all the way down) and small parts of AR and LA. The section has three titles:] Office Space Dazed and Confused Kill Bill [Small section around and below Chicago, IL, which is surrounded on three sides by the next large section mentioned below. It is labeled with an arrow:] Blues Brothers [Very small section almost a circle centered around Detroit, MI completely inside the section here below. It is labeled with an arrow:] 8 Mile [Large section covering all of WI, MI, IN and OH as well as parts of IL and KY. That is except for the two small sections described above, which are inlaid in this one. There are two items in this section. The one below is in smaller font:] A Christmas Story &That song about Jack and Diane [Medium section covering half of AR, small parts of IL and MO as well as bits of KY, TN and MS:] Anything by Mark Twain [Medium section covering half of TN and part of KY:] Walk the Line [Large section covering all of AL most of MS and half of GA. There are two titles in this section:] Big Fish O Brother Where Art Thou [Small section covering top of LA and small part of MS:] Duck Dynasty [Medium section covering the bottom half of LA and the very bottom of MS. There is a very small section at the bottom of LA that are not included in this but in the next. There are two titles in this section:] Princess and the Frog All Dogs go to Heaven [Small section covering the very eastern end of the bottom of LA – maybe including New Orleans. It is labeled with an arrow:] Beasts of the Southern Wild [Medium section covering half of PA and western part NY:] Groundhog Day [Small section covering the middle part of VA as well as small parts of PA, MD and WV:] Dirty Dancing [Medium section covering most of WV, half of TN, a small parts of KY as well as tiny bits of VA, NC and GA:] October Sky [Large section covering all of SC, most of NC as well as half of VA and GA. There are two titles in this section:] Gone with the Wind Forrest Gump [Large section covering most of FL except the bottom part which are covered by the next two sections:] The Truman Show [Small section covering the very bottom of FL except the east coast. It is labeled with an arrow:] Adaptation [Small section covering the very bottom the east coast of FL. It is labeled with an arrow:] Miami Vice [Small section covering most of the top of VT and a small part of NY. It is labeled with an arrow:] Super Troopers [Small section covering the central part of NY.] My Side of the Mountain (book) [Small section covering the eastern part of NY, western part of MA, top part of CT as well as bits of VT and RI.:] War of the Worlds (2005) [Small section covering the eastern part of PA and small bits of NY and MD. There are two titles in this section:] Signs & The Village [Medium section covering several large cities of the east coast including New York City, Philadelphia and Washington, DC. It covers most of DE and NJ and large parts of MD (with DC) and the bit of NY with the city. The text is not a title and the it is written in square brackets…:] [Generic city] [Small section covering the east coast along VA and NC, but also with small bits of MD and DE at the top:] Deep Impact [Medium section covering all of ME, the top tip of NH and eastern top of VT:] Pet Semetary [Small section covering the most of the bottom parts of NH and VT:] What about Bob [Very small section surrounding Boston in MA. It is labeled with an arrow:] The Departed [Small section covering the east coast along MA, RI, CT and NJ:] Jaws [Large section off the east coast in the Atlantic Ocean:] The Hunt for Red October

Napoleon

Napoleon

https://www.xkcd.com/1510

https://www.explainxkcd.com/wiki/index.php/1510:_Napoleon

[Two Cueball-like soldiers with guns present Napoleon (recognizable by his Napoleon hat, aka a bicorne ) to an officer sitting behind his desk. The officer is pointing at Napoleon who has a small chain on his hands.] Soldier at the front: This is Napoleon. He tried to take over the world. Officer Cueball: Exile him to Elba! [Three Cueball-like soldiers with guns present Napoleon again to the same officer sitting behind his desk. The officer has one hand held in front of him with his palm up. This time Napoleon has a larger chain on his hands and a ball and chain on his right leg. His head and hat is battered from the battle.] Soldier at the front: It's us again. Napoleon escaped from Elba and tried to conquer the world. Again. Officer Cueball: Send him someplace truly remote, like Saint Helena. Soldier at the front: Yes, sir. [At the top of the panel is a text in a frame that breaks the panel's frame:] Several Years Later... [Four Cueball-like soldiers with guns (one partly outside the frame) stand behind Napoleon and one more soldier stands in front of him as they again present him to the same officer. The officer is now standing behind his desk, holding it with one hand while the other is pointing up in the air. This time Napoleon has a octopus on his head, is dripping wet, still has the larger chain on his hands and the ball and chain on his right leg. Furthermore his legs are shackled. There are pools of water on the floor.] Soldier at the front: Well, he swam back. Officer Cueball: We must mount an expedition to the South Pole, where we will encase Napoleon in the Antarctic ice!" [At the top of the panel is a text in a frame that breaks the panel's frame:] A century later... [President Kennedy is giving a speech standing on a podium behind a lectern, while Napoleon is standing behind him with the same restraining devices as before. Napoleon now has icicles dangling from his hat and a small piece of ice on his right leg around the knee.] President Kennedy: We choose to go to the moon, not because it is easy...

Napoleon Bonaparte was one of the greatest military leaders in history, conquering most of Europe in the space of a decade. In 1814, after being forced to abdicate as Emperor of the French, he was exiled to the island of Elba . However, in February 1815 Napoleon escaped back to France, quickly raised an army, and overthrew the Bourbon Restoration monarchy for a period known as The Hundred Days . At the end of this period (actually lasting 111 days), Napoleon was defeated by British and Prussian forces at the Battle of Waterloo , and surrendered a month later. This time he was exiled to Saint Helena , an island much more remote than Elba—in fact, one of the most remote places on Earth. In reality, Napoleon made no serious attempts to escape Saint Helena, although Admiral Thomas Cochrane reports in his memoirs that while on his way to lead the fledgling Chilean Navy in their revolution against Spain he intended to stop at St. Helena in order to free Napoleon and put him in charge of all the South American rebel armies. In the event, before he arrived at the island he learned that Napoleon had died there, six years after his surrender. However, this comic imagines a world in which Napoleon escaped once again, swimming back to Europe. Saint Helena is 2,000 km (1,200 mi.) from the Afro-Eurasian landmass, making such a swim rather implausible, especially considering the ball and chain around his ankle. And Napoleon is depicted fresh out of the water, suggesting that he did not simply swim to Africa and make his way back to Europe, but rather swam straight to Europe, a journey of roughly 6,100 km (3,800 mi.). The comic implies that Napoleon proves impossible to confine, despite escalating attempts to send him to more remote locations and apply increasingly confining restraints (handcuffs, then adding a ball and chain on one ankle, then chaining the ball to both ankles). In addition to being able to swim impossible distances, he seems to also somehow escape imprisonment in the ice of Antarctica. He also seems to be immortal (or well-preserved by the ice of Antarctica), remaining alive and apparently in great physical condition while nearly 200 years old. The final panel shows U.S. President John F. Kennedy 's " We choose to go to the Moon " speech, but implies an alternate ending to the line "not because it is easy, but because it is hard." Rather, it appears that we choose to go to the Moon not because it is easy, but because it will be hard for Napoleon to return. The title text is an apparent conversation between President Richard Nixon and an aide. Nixon is asked what we will do if we fail to maroon Napoleon on the Moon, and replies "Have Safire write up a speech." This is a reference to Nixon speechwriter William Safire , who wrote the draft speech "In Event of Moon Disaster" , to have been delivered by Nixon should the Apollo 11 astronauts be stranded on the Moon. This comic thus proposes an inversion of the actual scenario—instead of Nixon delivering Safire's speech because someone's been stranded on the moon, in this comic he'd be delivering it if someone weren't stranded on the moon. "In Event of Moon Disaster" was also the topic of 1484: Apollo Speeches , published two months before this comic. In the title text of 1291: Shoot for the Moon the idea of missing the Moon, and ending up orbiting the Sun is the subject. [Two Cueball-like soldiers with guns present Napoleon (recognizable by his Napoleon hat, aka a bicorne ) to an officer sitting behind his desk. The officer is pointing at Napoleon who has a small chain on his hands.] Soldier at the front: This is Napoleon. He tried to take over the world. Officer Cueball: Exile him to Elba! [Three Cueball-like soldiers with guns present Napoleon again to the same officer sitting behind his desk. The officer has one hand held in front of him with his palm up. This time Napoleon has a larger chain on his hands and a ball and chain on his right leg. His head and hat is battered from the battle.] Soldier at the front: It's us again. Napoleon escaped from Elba and tried to conquer the world. Again. Officer Cueball: Send him someplace truly remote, like Saint Helena. Soldier at the front: Yes, sir. [At the top of the panel is a text in a frame that breaks the panel's frame:] Several Years Later... [Four Cueball-like soldiers with guns (one partly outside the frame) stand behind Napoleon and one more soldier stands in front of him as they again present him to the same officer. The officer is now standing behind his desk, holding it with one hand while the other is pointing up in the air. This time Napoleon has a octopus on his head, is dripping wet, still has the larger chain on his hands and the ball and chain on his right leg. Furthermore his legs are shackled. There are pools of water on the floor.] Soldier at the front: Well, he swam back. Officer Cueball: We must mount an expedition to the South Pole, where we will encase Napoleon in the Antarctic ice!" [At the top of the panel is a text in a frame that breaks the panel's frame:] A century later... [President Kennedy is giving a speech standing on a podium behind a lectern, while Napoleon is standing behind him with the same restraining devices as before. Napoleon now has icicles dangling from his hat and a small piece of ice on his right leg around the knee.] President Kennedy: We choose to go to the moon, not because it is easy...

Spice Girl

Spice Girl

https://www.xkcd.com/1511

https://www.explainxkcd.com/wiki/index.php/1511:_Spice_Girl

[Cueball is trying to barricade a door with his own body (although it already has a bar in front of it). He is in a room that is deteriorating with Hairbun who is loading a shotgun while sitting behind some sort of box.] Knocking on the door: Thump Thump Voice (see here ): Which Spice Girl are you?! Voice (see here ): The merciful one, or the one who started this war? [Caption below the frame:] When I see those quiz titles, I like to imagine they're being shouted through a door in a postapocalyptic dystopia.

The Spice Girls are a British pop girl group formed in 1994. It consists of five girls who each have a "spice girl" nickname. The five girls with their respective nicknames are: In 1554: Spice Girls he shows how difficult it is to remember these five names... This is one example of a trend of online quizzes that would "identify" the user with one person/personality of a group based on a series of personality questions. This will most often concern which member of a band, TV cast/film cast or character from books, etc. the quiz taker most resembles. In this comic it is specifically Spice girl quizzes that are the subject. In this comic, Randall is suggesting that in order to cope with what he probably considers to be irritating clickbait links to these quizzes, he imagines the link titles as being shouted through a door in a postapocalyptic dystopia . This is a reference to a trope in movies set in such postapocalyptic settings (which Randall presumably enjoys more) in which the heroes must determine whether an unknown agent is friend or foe, which in some such media occurs by shouting through locked doors. It is not likely that Randall would actually complete these quizzes, but if he did in this fantasy setting, the stakes would be higher and each answer would be fraught with dangerous meaning. It would thus also be much more fun taking the quiz and the result would seem to be important. In Randall's fantasy dystopian future, the character who is subject of the dialogue may be one of two Spice Girls, described alternately as the one who is merciful and the one started the war (which likely resulted in the said dystopia). It is possible there are only two remaining Spice Girls, or that there are simply only two likely options in the particular circumstances of the comic. It is also unclear if Randall may be suggesting two fictional Spice Girls, or if in his fantasy future, two of the actual original Spice Girls fit the criteria mentioned. The Merciful One could be a reference to the song with the same name by Zohar , another British music ensemble. As a result of the way a speech line was drawn in this comic, there was initially ambiguity as to the source of the dialogue. The official transcript now states: "A CRUEL INTERLOPER, external to the scene and room, pounds on the door and shouts at the two figures in our sight." The four little lines at the source end of the speech line are often used by Randall to denote sound coming from an unseen source. The quiz question is being shouted by an angry agent or crowd outside the door, presumably in reference to the female character seen in the comic. Presumably if she is "the one who started this war", the person(s) outside would be hostile toward her. In this case, it looks like the female character (who otherwise appears to be a Hairbun character) does not have any intention of answering, and is preparing for when the people outside break down the door by loading her shotgun to defend herself. In this interpretation, the title text is said by "Hairbun" Spice indicating that when they get through the door they will be in trouble. The title text refers to the lyrics from the Spice Girls' debut single, Wannabe (Listen to Wannabe on YouTube ) Here below is the relevant excerpt from the song where the letters in the last four lines refer to the spice girls as given above . This rap bridge is sung by Scary Spice except for the line with Easy V which is sung by Ginger Spice: So here's a story from A to Z, You wanna get with me You gotta listen carefully We got Em in the place who likes it in your face You got G like MC who likes it on an Easy V doesn't come for free, she's a real lady And as for me, ha ha, you'll see These lyrics function as a little introduction to the (then) less-well-known girl group. The final line takes on a threat-like tone in this new context of the comic. And it doesn't help that it is Scary Spice who sings it. The text may seem a little confusing to understand, especially the line that finishes on an . According to another lyrics-site, which also has explanations to some parts of the text, it means that G and MC likes it (sex) together with ecstasy - as "On an E" is slang for being on ecstasy (see it used in this discussion ). They could not sing this directly without resulting in a PG rating, thus they inserted the "E" in the next line as E asy V, a line which is even sung by another spice girl, Ginger spice, where the rest of this bridge is sung by Scary Spice. [Cueball is trying to barricade a door with his own body (although it already has a bar in front of it). He is in a room that is deteriorating with Hairbun who is loading a shotgun while sitting behind some sort of box.] Knocking on the door: Thump Thump Voice (see here ): Which Spice Girl are you?! Voice (see here ): The merciful one, or the one who started this war? [Caption below the frame:] When I see those quiz titles, I like to imagine they're being shouted through a door in a postapocalyptic dystopia.

Horoscopes

Horoscopes

https://www.xkcd.com/1512

https://www.explainxkcd.com/wiki/index.php/1512:_Horoscopes

[Above the frame:] Horoscopes With an actual basis in fact [A list with the name of each astrological sign in the first column (in gray) and a horoscope for each sign in the second column. Here given in table form] Aries • You may have been conceived after a 4th of July fireworks show Taurus • You may have been conceived on a hot August day Gemini • You may have been conceived as the leaves began to change Cancer • You may have been conceived by people trying on costumes Leo • You may have been conceived during Thanksgiving Virgo • You may have been conceived while a Christmas song played Libra • You may have been conceived after a New Year's Eve party Scorpio • You may have been conceived by people stuck inside after a long winter Sagittarius • You may have been conceived during March Madness Capricorn • You may have been conceived during a sexy Easter egg hunt Aquarius • You may have been conceived on Mother's day Pisces • You may have been conceived at someone's wedding

Horoscopes purport to predict someone's personality or future, based on the position of planets and stars at the time of their birth and at present. Horoscopes commonly group people into twelve groups based on zodiac signs . The names of the horoscope Zodiac signs are based on the names of twelve constellations that were the backdrop for the path of the sun in the ancient times when the rules of settings horoscopes were originally developed. Today, due to precession of the Earth's axis of rotation (and to a lesser degree due to the modern formal definitions of constellations), the Zodiac signs do not correspond fully to the names of actual constellations in the path of the Sun. One's zodiac sign is determined by the position of the sun on their birthday, with each sign representing a specific 30.4 day period (1/12th of a year), starting from the First point of Aries . Modern science has found no basis for horoscopes , which is why the comic jokes about the fact that its horoscopes at least may be true. Actual horoscopes are typically so vague that they could be true for almost anyone regardless of their sign. Note that this horoscope mainly makes sense for people living in the northern hemisphere (as mentioned in the title text) and it is especially tailored for an audience in the United States , as most cultural references are centered on "Western" or even specific "American" culture, several won't even work in Europe, for example. However, with the principle understood, it is easy to apply local traditions for more accuracy in non-Western cultures. The 12 category zodiac signs in horoscopes are based on birth dates. The average length of pregnancy, culturally considered to be nine months, is actually given as the 40 weeks (9.2 months) after the last menstrual period. However, what is relevant here is that it is only 38 weeks after conception (8.75 month). The first two weeks of the 40 week period is before Ovulation , and the conception cannot occur before that. Based on this knowledge Randall can do some informed guessing about the context of someone's conception (apart from the obvious ), depending on the sign. For example, people of the sign Virgo have been born between August 23 and September 22. This makes it most likely that they are conceived during December the year before. Given contemporary holiday music preferences, Christmas songs were likely to be playing the day they were conceived. This leads to the guess "You may have been conceived while a Christmas song played". See detailed description of all the signs and explanation of the horoscopes in the table below. Randall phrases his "predictions" as possibilities ("you may have") rather than declarations, acknowledging that it is a guess, and that it, unlike actual horoscopes, doesn't necessarily apply to everyone. The title text refers to the Coriolis effect which applies to a body that is moving relative to an object that is spinning. Since the Earth is rotating, a force (the Coriolis force) causes moving objects to be deflected to the right in the northern hemisphere and to the left in the southern hemisphere . This effect is the reason that weather systems (most clearly seen for hurricanes ) spiral in one direction in the northern hemisphere and in the opposite direction in the southern hemisphere. There is also a common misconception that the Coriolis force in respect of the Earth affects objects on a much smaller scale, such as the direction water will spiral down a drain in the two hemispheres (see also 843: Misconceptions ). In reality, the relative rotational speed of the Earth (one rotation per day) is insufficient to affect anything but large-scale, relatively slow movement, such as prevailing winds and ocean currents . Randall plays on this type of misconception to make a joke involving reversing the flow of time. So whereas babies are born nine months after conception in the northern hemisphere (clockwise) the Coriolis effect is the reason why babies are being born nine months before in the southern hemisphere (counterclockwise). Note that unlike these horoscopes, which are declared to have an "actual basis in fact", it makes no sense for the conception of a baby to happen after its birth [ citation needed ] . Here below is a table with data and explanation of the individual horoscopes: [Above the frame:] Horoscopes With an actual basis in fact [A list with the name of each astrological sign in the first column (in gray) and a horoscope for each sign in the second column. Here given in table form] Aries • You may have been conceived after a 4th of July fireworks show Taurus • You may have been conceived on a hot August day Gemini • You may have been conceived as the leaves began to change Cancer • You may have been conceived by people trying on costumes Leo • You may have been conceived during Thanksgiving Virgo • You may have been conceived while a Christmas song played Libra • You may have been conceived after a New Year's Eve party Scorpio • You may have been conceived by people stuck inside after a long winter Sagittarius • You may have been conceived during March Madness Capricorn • You may have been conceived during a sexy Easter egg hunt Aquarius • You may have been conceived on Mother's day Pisces • You may have been conceived at someone's wedding

Code Quality

Code Quality

https://www.xkcd.com/1513

https://www.explainxkcd.com/wiki/index.php/1513:_Code_Quality

[Cueball showing Ponytail his laptop.] Cueball: Keep in mind that I'm self-taught, so my code may be a little messy. Ponytail: Lemme see - I'm sure it's fine. [Ponytail sits at desk, Cueball stand behind her.] Ponytail: ...Wow. This is like being in a house built by a child using nothing but a hatchet and a picture of a house. [Same scene.] Ponytail: It's like a salad recipe written by a corporate lawyer using a phone autocorrect that only knew Excel formulas. [Same scene.] Ponytail: It's like someone took a transcript of a couple arguing at IKEA and made random edits until it compiled without errors. Cueball: Okay, I'll read a style guide.

This comic is the first in the Code Quality series: It is about the apprehension of asking for help from an expert who is a friend. Often we fear that we will be judged and they will think less of us, which is what occurs in this comic. Ponytail is about to look at some source code Cueball has written, and he is warning her that he is self-taught so his code probably won't be written the way she is used to. In spite of Ponytail's initial (polite) optimism, she comments in three increasingly harsh similes (and a fourth in the title text). First, she suggests that reading his code is like being in a house built by a child, using a hatchet (a small axe) to put together what he thought was a house based on a picture. She is saying that the code shows a lack of command of the language being programmed. This is like the common expression "If all you have is a hammer, everything looks like a nail." New programmers make use of the same techniques repeatedly, using them for situations where other techniques would be far more efficient or faster. Second, she suggests that it looks like a salad recipe, written by a corporate lawyer on a phone with auto-correct that only corrects things to formulas from Microsoft Excel. She is saying that the code is verbose and the corrections that were done are illogical. This presumably relates to the developer not being an expert in their craft, and fixing the problems as they come up instead of re-examining the problem and solving it in a better way. Third, she describes it as a transcript of a couple arguing at a branch of the Swedish retail chain IKEA , that was then randomly edited until the computer compiled it with no errors. She is saying that the intent of the code is unclear due to the seemingly random use of the language. This is very similar to an infinite amount of monkeys bashing away on typewriters for an infinite amount of time that will eventually produce the complete works of Shakespeare. (A couple's argument may be even less coherent at IKEA than at the average store, since IKEA products always have idiosyncratic names and many of them are difficult to pronounce or transcribe for anyone who doesn't speak Swedish.) This might happen if the code was written so badly that it does not compile, and people edited the code until it compiles so they can see what the code accomplishes. The fact that Cueball's code is in this bad of a shape indicates he really hasn't learned the programming language; he just happens to have a program that works in some shape or fashion. Finally, Cueball makes the rather weak assurance that he will read "a style guide", which articulates the intended use of the language. It seems clear from Ponytail's commentary that his code quality would benefit from far more training in computer programming. The title text refers to emoji . Ponytail's comment implies that some of Cueball's variables contained emoji, perhaps in an effort to capture the emotional content of the arguments which show through the requirements document. Emoji have become a recurrent theme on xkcd, but this may have been the first comic to use them for a pun. Many crying-face emoji are possible if variables can include full Unicode (e.g., 😢,😭,😂,😿,😹), as well as faces with sweat drops that are often mistaken for tears (😪,😥,😰,🥵). In some programming languages it would be impossible to use them in variable names, as the symbols would break the language's syntax rules. Exceptions to this include Swift and Perl ( [1] ), but most languages with compilers that support Unicode characters can include this kind of emoji, even for languages that predate Unicode like C++ and Lisp . In any event, Cueball's code may best be represented by a bunch of people crying, as that seems to be the only proper response to it. Although few programming languages require a perfectly rigid style, so long as the code is syntactically accurate, most programmers follow some sort of style to make the code easier to read. This includes indenting lines to show levels and using descriptive variable identifiers with special capitalization, (e.g., camelCase , capitalizing each word except for the first in a sentence, or snake_case , separating lowercase words with underscores). [Cueball showing Ponytail his laptop.] Cueball: Keep in mind that I'm self-taught, so my code may be a little messy. Ponytail: Lemme see - I'm sure it's fine. [Ponytail sits at desk, Cueball stand behind her.] Ponytail: ...Wow. This is like being in a house built by a child using nothing but a hatchet and a picture of a house. [Same scene.] Ponytail: It's like a salad recipe written by a corporate lawyer using a phone autocorrect that only knew Excel formulas. [Same scene.] Ponytail: It's like someone took a transcript of a couple arguing at IKEA and made random edits until it compiled without errors. Cueball: Okay, I'll read a style guide.

PermaCal

PermaCal

https://www.xkcd.com/1514

https://www.explainxkcd.com/wiki/index.php/1514:_PermaCal

[Megan and Cueball are in the panel. Cueball appears to be holding a phone, tapping.] Megan: What day is it? Cueball: Sunday the 19 th . Megan: But you said it was the 19 th yesterday. Cueball: It changed again ? Crap, better add another leap day. [Caption below the panel:] My simplified calendar system assumes the date never changes, then corrects any drift via leap days.

This comic proposes a new calendar system, named PermaCal (a malamanteau of the words "permanent" and "calendar"). In it, the date stays constant. In order to accomplish that, as each day passes, it is interpreted as "drift", and a new PermaCal leap day (analogous to the leap day of the Gregorian calendar ) is added to compensate. In the comic, which was published on Monday April 20, 2015, Megan wonders why today would be the 19th, since Cueball said it was the 19th a day ago. Cueball interprets the news from Megan, that a day has passed, as "drift" in the date, and resolves to add another leap day to PermaCal so that his calendar will be correct. He is presumably becoming frustrated that he has to do this so often. Leap days in the Gregorian calendar are days added to the end of February every year that is a multiple of 4, but not by 100, unless it's also a multiple of 400. The purpose is to synchronize the calendar with Earth's orbit without having a partial day each year. Leap seconds are necessary because the earth rotation is not constant, but speeds up and slows down over time. The leap seconds account for the differences in the length of our 24 hour day and a solar day (the time taken for Earth to rotate once with respect to the sun), and are announced several months beforehand. NTP servers are used to keep local computer time from drifting. They also are used to announce Leap seconds . In the context of this comic, leap seconds would refer to a different system in which there is a new leap second each second, so the time also stays constant, down to the resolution of one second. This would require something like setting the NTP leap second bit anew every second. The title text presumably refers to moving to a resolution of one millisecond via leap milliseconds. This would require at least 1000 updates being requested every second, using enormous network bandwidth and resulting in a Distributed Denial-of-service attack (DDoS) situation. The comic relates to several DDoS problems due to NTP server misuse and abuse over the years. Part of the humor stems from the problems that leap seconds are causing for some computers. [1] The last leap second disrupted computers at big companies such as Reddit , LinkedIn , Gizmodo and FourSquare . Google first introduced a new approach of smearing the leap second , smoothly changing the reported time over an undisclosed number of hours around midnight UTC on December 31, 2008. The smooth shape of the adjustment is graphed at synchronization - Math behind Google leap second smear formula - Stack Overflow . A new calendar was also proposed in comic 1061: EST . [Megan and Cueball are in the panel. Cueball appears to be holding a phone, tapping.] Megan: What day is it? Cueball: Sunday the 19 th . Megan: But you said it was the 19 th yesterday. Cueball: It changed again ? Crap, better add another leap day. [Caption below the panel:] My simplified calendar system assumes the date never changes, then corrects any drift via leap days.

Basketball Earth

Basketball Earth

https://www.xkcd.com/1515

https://www.explainxkcd.com/wiki/index.php/1515:_Basketball_Earth

[Cueball is standing next to a floating Basketball Earth indicating it with his left hand. The continents are clearly visible as seen from above the Atlantic Ocean. This remains the same all through the comic, except that the Basketball Earth rotates a bit from frame to frame.] Cueball: If the Earth were the size of a basketball, [Cueball is now indicating, with his right hand, a small pockmarked moon (also floating), in the correct proportions (regarding size not for their distance) to the Basketball Earth, which is on his other side. Black Hat walks into the panel towards Earth.] Cueball: The Moon would be— Black Hat: Hey, cool! [Black Hat is touching the Basketball Earth with a digit.] Cueball: Um. [In the next scene, we see a megatsunami on the verge of crashing down onto a coastal city with skyscrapers. The A's are cut off on each side of the panels frames, i.e. they begin outside and finish outside the frame.] AAAAAAAA [Back to Cueball standing with the Basketball Earth in the same position as the first panel.] Cueball: Let's try that again. If the Earth were the size of a basketball, [Same situation as when Black Hat walked in, except now it is Megan that walks into the frame towards the Basketball Earth holding a sports water bottle.] Cueball: The Moon would be— [Megan squirts the Basketball Earth with the liquid in her water bottle while Cueball just stands watching with the Moon behind him]. [Megan just walks away while Cueball stares at his "water" Basketball Earth where the continents have disappeared completely beneath the liquid.] [Back to Cueball standing with the Basketball Earth in the same position as the first panel.] Cueball: If the Earth were the size of a basketball, [Same situation as when Black Hat walked in, except now he spots a cat coming into the frame from the left.] Cueball: The Moon— would… [While Cueball watches with the Moon behind him, the cat jumps at the Basketball Earth.] Cat: Mrowl! [Cueball continues to watch while the cat rolls around playing with the Basketball Earth as if it was a ball of yarn.] Cat: Rrrrr [Back to Cueball standing with the Basketball Earth in the same position as the first panel.] Cueball: If the Earth were the size of a basketball, [Same situation as when Black Hat walked in, except this time it is Ponytail who enters the frame at a run coming from the left.] Cueball: The Moon would, uh… [While Cueball watches with the Moon behind him, Ponytail has grabbed the Basketball Earth and is dribbling it out of the frame, still running.] [Zoom out from Cueball who continues to watch while Ponytail reaches a basketball hoop and jumps towards it with the Basketball Earth, obviously in an attempt to make a slam dunk.]

In this comic Cueball is repeatedly attempting to make a size comparison between the Earth and the Moon . But he only gets to say If the Earth were the size of a basketball, the Moon would be- . Then he is interrupted again and again. (See the title text of 1074: Moon Landing for the same Earth comparison). A basketball is about 25 cm in diameter and from this it can be inferred that the Moon should then be less than 7 cm in diameter, a typical size for other smaller balls in different sports. Cueball handily illustrates this with two "balls" of the relevant sizes. At first, you think that they just look like the Earth and the Moon. But they are invisibly suspended, and — as seems clear from the first row of panels — they are actually the real Moon and Earth shrunk to the relevant size, hence the title Basketball Earth . This would place Cueball and his "friends" in God -like positions, outside Earth. Maybe they are even in a different dimension since they can stand and observe the system. But before Cueball can finish with this common type of comparison, he is interrupted and must begin all over again. We thus never learn what object he would have compared the Moon with. It seems, likely, however, that he would use another ball for the comparison. And the best ball to use would be a tennis ball . See the same sort of comparison of Earth/Moon with basketball/tennis ball in this illustrative video that asks the question: How far away is the Moon? . From this, it is also obvious that the system Cueball shows is not to scale with regard to that distance, which should be 7.37 m! This is not necessarily a mistake of the comic, since Cueball never claims that these two balls are in orbit or that they are even the real ones. He is just (in vain) trying to make a size comparison of the two. (Though perhaps further exposition and demonstration might take place after the size comparison.) A basketball has an average diameter of 24.6 cm (9.7 inches) vs. a tennis ball, which has an average diameter of 6.7 cm (2.6 inches). The ratio between these two diameters is 0.273, which is the same (to three digits) as the ratio given on the Wikipedia page for the Moon: Mean radius 1737.10 km (0.273 Earths) . If he had used a baseball , which is slightly larger, this would still be good enough for demonstrative purposes, as it would have been with an apple. It is common to describe the relationship between very large (and very small) objects by analogy to common objects on a more human scale. Here is a similar example where someone has made a comparison of the sizes of the Solar system based on a Sun the size of a basketball . And here, coming from smaller scales, is an example that states the following: "Imagine an atom magnified to the size of a football stadium. The nucleus of the atom would be the size of a pea in the centre of the stadium." It is almost certainly not a coincidence that this comic was released on Earth Day , which is celebrated annually on April 22 to demonstrate support for environmental protection. This seems to be something that Randall cares about a lot, as he has made several comics demonstrating the need for the human race to begin taking better care of our globe. See, for instance, 1321: Cold and 1379: 4.5 Degrees . This comic clearly demonstrates four examples where the inhabitants of Earth did not take care of the well being of our globe, although here on a somewhat grander scale than what individuals can usually do. The typical case is that people did not do this out of bad intentions, but only because they were careless, curious, playful, or just plain stupid. This comic may be seen as a spiritual successor to 445: I Am Not Good with Boomerangs and its follow-up, 475: Further Boomerang Difficulties in depicting various failed outcomes to the same opening panel. The four interruptions are described and explained below. Each of the four attempts has its own row of four panels in the comic. It is clear from panels one and two in each row that the Basketball Earth is rotating quite fast compared to the time frame of the comic since the continents have moved considerably between frames. It is thus not necessarily the interrupters that have moved the Basketball Earth between frames two and three, except of course in the final interruption. No matter how fast it rotates or whatever happens, we always see the Basketball Earth from the same side, as seen from far above the Atlantic Ocean . We can see the continents of the Americas as well as Africa and sometimes part of Europe , all of which are the borders for this ocean. It seems most likely that Cueball starts all over every time, with a completely fresh and new Earth-Moon system, since they look the same regardless of the catastrophe befalling the prior Basketball Earth, and the interruptions—the second especially—would be difficult to reverse. We can thus suppose that there is still "normal" life going on for each Basketball Earth before the interruption. Most or all of this life would presumably perish for all of the last three cases. In the first interruption, Black Hat comes in and is amazed by this cool floating globe. Of course, being Black Hat, he has to prod this nice globe with a digit. But by putting his finger into one of the oceans of this "real" Basketball Earth without a second thought, he apparently generates a megatsunami that rolls in over an unidentified city with skyscrapers, utterly dwarfed by a breaking wave. This is similar to a scene in " Men in Black II " where K messed with a globe that actually is a small planet, and his finger becomes visible in the sky of its inhabitants. It is also similar to a "Pearls before swine" strip where the character Pig encounters Atlas and the earth in a diner, points to where he lives, and accidentally pokes himself in the eye. It is also reminiscent of Deep Impact in which a meteor strike causes exactly such a tsunami to hit the East Coast of the United States . Since Black Hat puts his finger down in the Atlantic Ocean, the tsunami would hit all bordering coastlines. Since the coast seems to be an eastern coast (assuming a vantage point of South --> North), and because Randall lives there, the city could be New York City or Boston or one of the other large US cities on the East Coast. Of course, the wave would also affect the coastline (far into land) for all the other continents. The second interruption occurs when Megan arrives and pours liquid (perhaps water) from a sports water bottle onto the Basketball Earth, seemingly flooding its entire surface. This would cause extensive flooding , almost certainly extinguishing all multicellular land-dwelling life. The most familiar analogous situation is from the Bible in the Genesis flood narrative about Noah's Ark . The deluge from Megan's bottle would also change the composition of the ocean and create enormous churn and pressure changes, with widespread or catastrophic effects even on multicellular marine life. And if it were some sort of sports drink inside... In the third interruption, a cat walks into the shot and then playfully attacks the Basketball Earth, rolling around like it would do with a ball of yarn (see real-life example in this video ). This also seems to be an allusion to the logo of the popular web browser Mozilla Firefox, which depicts a fox curled around the earth in a similar manner to that shown in the comic. The people living upon this Basketball Earth would experience cataclysmic events far greater than Blackhat's digital prodding caused, especially as the Basketball Earth is no longer suspended and was thus taken "out of its orbit" and will eventually hit the floor very hard. One way or another, that will surely cause (undepicted) disasters of tremendous magnitude. In the fourth and final interruption, Ponytail uses Basketball Earth as an actual basketball. She comes running by Cueball, grabs the Basketball Earth, probably bouncing it off the floor while dribbling towards the basketball hoop where she actually jumps in an attempt to dunk the Basketball Earth. This would not be good for any residents of Basketball Earth [ citation needed ] ; the combined pressure, movement, and impact damage from this simple sequence would surely kill off all complex life on Basketball Earth. This simile-callback is continued in the title text with the idea that "every basketball in existence" (i.e., every basketball upon the Basketball Earth, as well as the Basketball Earth itself) is counted towards the score from a single dunking. Randall may have a good estimate of how many basketballs there are, perhaps through research for some what if? question or other research, but almost certainly assumes that there are no extraterrestrial basketballs not on Basketball Earth. But there might be some question about whether the Basketball Earth's own sub-scale basketballs fall within the regulations. If we go by the strict rules of league Basketball, the answer would only be two points , as it is illegal to have more than one basketball in play at a time. [Cueball is standing next to a floating Basketball Earth indicating it with his left hand. The continents are clearly visible as seen from above the Atlantic Ocean. This remains the same all through the comic, except that the Basketball Earth rotates a bit from frame to frame.] Cueball: If the Earth were the size of a basketball, [Cueball is now indicating, with his right hand, a small pockmarked moon (also floating), in the correct proportions (regarding size not for their distance) to the Basketball Earth, which is on his other side. Black Hat walks into the panel towards Earth.] Cueball: The Moon would be— Black Hat: Hey, cool! [Black Hat is touching the Basketball Earth with a digit.] Cueball: Um. [In the next scene, we see a megatsunami on the verge of crashing down onto a coastal city with skyscrapers. The A's are cut off on each side of the panels frames, i.e. they begin outside and finish outside the frame.] AAAAAAAA [Back to Cueball standing with the Basketball Earth in the same position as the first panel.] Cueball: Let's try that again. If the Earth were the size of a basketball, [Same situation as when Black Hat walked in, except now it is Megan that walks into the frame towards the Basketball Earth holding a sports water bottle.] Cueball: The Moon would be— [Megan squirts the Basketball Earth with the liquid in her water bottle while Cueball just stands watching with the Moon behind him]. [Megan just walks away while Cueball stares at his "water" Basketball Earth where the continents have disappeared completely beneath the liquid.] [Back to Cueball standing with the Basketball Earth in the same position as the first panel.] Cueball: If the Earth were the size of a basketball, [Same situation as when Black Hat walked in, except now he spots a cat coming into the frame from the left.] Cueball: The Moon— would… [While Cueball watches with the Moon behind him, the cat jumps at the Basketball Earth.] Cat: Mrowl! [Cueball continues to watch while the cat rolls around playing with the Basketball Earth as if it was a ball of yarn.] Cat: Rrrrr [Back to Cueball standing with the Basketball Earth in the same position as the first panel.] Cueball: If the Earth were the size of a basketball, [Same situation as when Black Hat walked in, except this time it is Ponytail who enters the frame at a run coming from the left.] Cueball: The Moon would, uh… [While Cueball watches with the Moon behind him, Ponytail has grabbed the Basketball Earth and is dribbling it out of the frame, still running.] [Zoom out from Cueball who continues to watch while Ponytail reaches a basketball hoop and jumps towards it with the Basketball Earth, obviously in an attempt to make a slam dunk.]

Win by Induction

Win by Induction

https://www.xkcd.com/1516

https://www.explainxkcd.com/wiki/index.php/1516:_Win_by_Induction

[There is a long queue of Pikachu extending out of the frame to the left. They are all just out from their ball, at least the last eight Pikachu's open balls lie in two parts on the ground at their feet. They are standing in front of Megan and Cueball. Cueball is holding a closed pokéball while Megan checks the time on her watch. The frontmost Pikachu, holding a closed pokéball, speaks.] Pikachu at the front: Pikachu, I choose you!

In the Pokémon franchise, human characters called Trainers capture fantastical creatures from the wild, the titular Pokémon (a shortened form of "Pocket Monsters"), and train them to battle one another. Pokémon are captured and stored in devices called Poké Balls, which shrink the creatures down to pocket size (hence "Pocket Monsters"). The anime's English dub has enshrined the phrase " <Pokémon's name> , I choose you!" into popular culture memory. When Trainers do battle, they often shout this phrase while throwing the ball to the ground, releasing the Pokémon at full size. In this comic, a Pokémon chosen at some point was a Pikachu (the "poster child" for Pokémon, and the most publicly-known type), which does not intend to engage in the battle himself. Instead, the Pikachu chooses another Pikachu to fight for him. This process then repeats itself. Behind the Pikachu with the Pokéball is a long line of other Pikachu, suggesting that this process has been going on for a while. Nearby stands Cueball , holding a closed Pokéball, and Megan , looking at her watch. This suggests that Cueball intends to have his own Pokémon fight the Pikachu, but is waiting to see which enemy his Pokémon must face before the battle can actually begin (waiting in vain, if the above described process repeats indefinitely), while Megan is growing impatient with the delay. Given that Cueball is holding a closed Pokéball he has not deployed yet, Megan cannot herself be his Pokémon. She could be his opponent, or a spectator. The joke in this comic comes from analogy with the mathematical proof by induction , which is a proof about a base case, followed by a never ending sequence of steps, each step leading to the next. Induction proves an assertion is true for one case, and then infers that it must also be true for all related cases. The title suggests that the process of Pikachu choosing Pikachu will never end, effectively postponing the battle indefinitely. But the title is win by induction, by which Randall implies that we have been given enough information to reason logically whether Megan or Cueball will win. We have here turned mathematical induction on its head: part of the humour in the comic is that the logic of induction doesn't work in reverse. We cannot reason about an initial case by inferring something from a related case whose proof is dependent on knowledge about the initial case. Or perhaps the "win" referred to is precisely that the battle is indefinitely postponed. The name "induction" comes from logic and discrete mathematics, and is thus unrelated to the physical phenomena of electromagnetic induction ; but the fact that Pikachu is an "Electric-type" Pokémon could be word play connecting the two ideas. If there were always only a single Pikachu in each Pokéball, this would spawn an unlimited number of Pikachu growing at a constant rate. Since, as the title text notes, there are occasionally two of them in a Pokéball, this would lead to exponential growth assuming each of the spawned Pikachu in this case is bearing a Pokéball! This may be a reference to the rate of twins, which is approximately 1/30 in humans. Pikachu was used in one of the storylines of 1350: Lorenz . See all the attack moves it made here . [There is a long queue of Pikachu extending out of the frame to the left. They are all just out from their ball, at least the last eight Pikachu's open balls lie in two parts on the ground at their feet. They are standing in front of Megan and Cueball. Cueball is holding a closed pokéball while Megan checks the time on her watch. The frontmost Pikachu, holding a closed pokéball, speaks.] Pikachu at the front: Pikachu, I choose you!

Spectroscopy

Spectroscopy

https://www.xkcd.com/1517

https://www.explainxkcd.com/wiki/index.php/1517:_Spectroscopy

[A dark panel with a bright star in the center. To the left a planet (drawn as a new moon) approaches the star. Text is written above in white with two musical notes, one on each side of the text.] I watch the sunlight [Same image but now the planet transits the star. Small lines around the planet indicate the atmosphere, as seen from the light from the star passing through it. Text is again written above in white with two different musical notes, one on each side of the text.] Dance across your face [A white frame with a black line. It Is the spectrum of the planets atmosphere. Two distinct absorption peaks are visible. The first one is labeled with an arrow. Text is again written above, now in black, with two, again, different musical notes, one on each side of the text.] I can see you breathe Label: O 2 [Below the panels is the following caption:] Faith Hill on exoplanet spectroscopy

This comic mixes the method of using spectroscopy to detect oxygen on exoplanets (planets outside our Solar system ) with the lyrics for the Faith Hill song " Breathe " (listen to "Breathe" on YouTube ). From the lyrics: I watch the sunlight dance across your face I can feel you breathe In the comic the word "feel" has been changed to "see". The two first panels are one line in the song. The last line is from the chorus and is repeated five times during the song, although not right after the first two lines. In the first and second panel the singer examines the spectra of a remote planet by watching the sunlight during the transit of the planet as this sunlight dances across the planet's face . Finally we determine that breathable oxygen exists. Since we cannot (as Faith can) feel the planet we have to see it. And by doing this I can see you breathe . Measuring the light output of stars (spectra) we are able to determine a number of details of the star, including rotation, relative radial velocity, chemical composition, temperature, and to some degree, distance and size. When a planet, as pictured, moves between the star and the observer, then by looking at the spectrum received, the viewer is able to determine the contents of the planet's atmosphere from the specific wavelengths of light that are absorbed in this. If it turns out that the atmosphere absorbs the lines corresponding to molecular oxygen (O 2 ) this is a clear indication that the planet has large quantities of breathable oxygen (but not necessarily life ). However, there must be oxygen in large amounts in the atmosphere to sustain most of the life forms that we know of here on Earth (though not all ). It is thus clear why Randall would be interested in exoplanets with oxygen. This comic came out four days after this article about NASA's New NExSS Initiative . NASA will search for signs of life on other planets, for instance by using "the light passing through the atmospheres of these exoplanets". And they "will study chemicals that have been detected on other worlds, such as oxygen and methane, to see if they were produced by biology". The title text refers to determining radial velocity in the ESPRESSO program (Echelle SPectrograph for Rocky Exoplanet- and Stable Spectroscopic Observations). By noting that the radial velocity of the star changes slightly as the planet that orbits it moves around the star (centrifugal acceleration), the ESPRESSO program should be able to detect the masses of planets as they are moving towards the Earth in their orbit around their distant stars. The ESPRESSO program is so precise that it should be able to detect planets as small as Earth and the other of the Solar system's inner planets. Randall is now even more excited about ESPRESSO than he is about the oxygen levels, because it is now possible to detect these "very" small planets. So he is no longer listening to "Breathe", but to another Faith Hill song: " This Kiss " (listen to "This Kiss" on YouTube ). From the lyrics : It's centripetal motion On the rooftop under the sky The first line is part of the chorus and it is repeated four times, but Randall has changed the main word to "centrifugal". There is, however, disagreement on-line whether it is centripetal or centrifugal. The second line is not sung in connection with the chorus, and it is only changed a bit, so "the" is changed to "a". Also the "on" which is part of his line here is not part of the quoted line in the title text. The song is not about measuring but, of course, about "The Kiss". Since the ESPRESSO is part of the Very Large Telescope , it is located on the Cerro Paranal mountain in the Atacama desert in Chile at an elevation of 2,635 meters (8,645 ft.) above sea level. So it could be said that it is measuring on a rooftop under the sky. Although it is radial velocity it measures, not centrifugal motion , the object it does measure will all be experiencing this fictitious force (also see 123: Centrifugal Force ), as the planets are in orbit around a star. Randall has previously made several references to exoplanets in his comics, most notable are the two comics with the same name: 786: Exoplanets and 1071: Exoplanets . The latter comic came out when there were exactly 786 exoplanets found. Today more than 1900 have been discovered (1915 as of Wikipedia on the release day of this comic), much more than twice that amount. And now they can find even smaller planets, and detect the atmosphere. Much have happened since the first exoplanet comic came out in 2010. Five comics later in 1522: Astronomy he mentions astrobiology in the title text, closely relating it to this comic. [A dark panel with a bright star in the center. To the left a planet (drawn as a new moon) approaches the star. Text is written above in white with two musical notes, one on each side of the text.] I watch the sunlight [Same image but now the planet transits the star. Small lines around the planet indicate the atmosphere, as seen from the light from the star passing through it. Text is again written above in white with two different musical notes, one on each side of the text.] Dance across your face [A white frame with a black line. It Is the spectrum of the planets atmosphere. Two distinct absorption peaks are visible. The first one is labeled with an arrow. Text is again written above, now in black, with two, again, different musical notes, one on each side of the text.] I can see you breathe Label: O 2 [Below the panels is the following caption:] Faith Hill on exoplanet spectroscopy

Typical Morning Routine

Typical Morning Routine

https://www.xkcd.com/1518

https://www.explainxkcd.com/wiki/index.php/1518:_Typical_Morning_Routine

[The panel is completely black, with white text. Small lines indicate from where the two voices are coming, and also from where the alarm goes off. A small broken square surrounds the first word spoken.] Alarm: Bleep Bleep Voice (right): Urgh Voice (left): Your alarm is going off Voice (right): Huh? Voice (left): Make it stop. Voice (right) Urrgh [The panel is completely black, with white text. Small lines indicate from where the two voices are coming. Several small lines surrounds the last "sound" which is not spoken. The alarm noise is continued from the previous panel and continues over the top of the frame directly into the next panel.] Alarm: Bleep Bleep Bleep B Voice (left): Hit snooze. Voice (right): I'm trying . I closed the alarm app and I can't... I'll just pop out the battery. Voice (right): Whoops! Clang [The lights have turned on so it is now a white panel with black text. The voice to the right came from Hairy with morning hair. He is leaning over the side of the bed, looking down the air vent through which he has dropped the phone. The other person to the left is not shown. The alarm noise (now coming from the air vent as visualized by the lines coming out of the vent) still continues from the previous panel and continues over the top of the frame directly into the next panel.] Alarm: eep Bleep Bleep Ble Off-Screen voice: Make it stop! Hairy: It... fell down the vent. [Hairy is sitting in his bed with a laptop. The person to the left is still off-screen. The alarm noise still continues from the previous panel and continues over the top of the frame out of the comic the the right.] Alarm: ep Bleep Bleep Bleep Ble Off-Screen voice: Can you brick it remotely? Hairy: Trying... I think I fumbled it into airplane mode? Off-Screen voice: The battery could last for weeks. Hairy: You know, maybe we should just move. This comic follows a similar storyline to 349: Success and 530: I'm An Idiot , where Cueball , like Hairy here, encounters an issue and attempts progressively more absurd solutions. There is a callback to this in the title text of 1946: Hawaii .

Waking up to an alarm can be annoying, especially when it is your partner's alarm, and they are slow to wake up and even then have difficulty figuring out how to turn the alarm off. This comic takes this situation to a ridiculous extreme, from whence the comic derives its humor, especially when paired with the title describing this situation as a "Typical Morning Routine". Of course the typical could refer only to the part of the "routine" until the phone is dropped into an air vent. In this comic, Hairy with morning hair is shown using his smartphone as his alarm clock. Another unseen person is sharing the bed with Hairy and growing more irate as Hairy's alarm continues beeping. Even simple actions like turning off an alarm can be easily fumbled by a just-awakened groggy person. In this case, Hairy accidentally exited the alarm app without stopping the alarm. In some OSes, simply exiting the app doesn't close it, requiring you to use the app switcher to close it. After giving up on shutting down the alarm the usual way, Hairy, in annoyance, decides to remove the battery, which will disable the phone's entire operation. However, while trying to remove the battery in the dark, he accidentally drops his device down a floor air vent (most likely part of forced air central heating common in North America) next to the bed. While the vent is covered by a grille, it is apparently coarse enough (or perhaps missing a few pieces, creating a large hole) to allow the phone to pass through if it falls at a particular location and angle. Also, the vent apparently does not descend very far before bending, allowing the phone to survive the fall intact. As of when this comic was posted, Randall uses both iOS and Android according to 1508: Operating Systems —although there is no reason to be certain that the character in this comic is using the same operating systems as Randall. However, the fact that Hairy tries to remove the battery strongly suggests it cannot be an iOS device, given that all iOS devices have non-removable batteries. If he were a little handy, Hairy might be able to open the vent and retrieve the phone—or perhaps not, if the phone slid further into the ventwork or Hairy lacked the necessary tools. Instead of trying to physically recover the phone, Hairy attempts to remotely brick the phone from his laptop, permanently disabling all its functions (including the alarm app). This attempt fails because Hairy had accidentally put the device into airplane mode before dropping his phone, thereby cutting off all wireless communications with the device and preventing any attempt at remote control. Airplane mode also has the unfortunate (in this situation) side effect of increasing the phone's battery life (though playing loud sounds incessantly should still limit it to a day or so, notwithstanding the pessimistic assessment of Hairy's companion). Rather than finding a solution to the problem with the phone, Hairy proposes that they just move out instead. Relevant for the title text: There is a semi-common logic puzzle involving a ping-pong ball falling down a pipe with a kink in it. In this puzzle, the solution is to pour water into the pipe until the ping-pong ball floats up. In the title text, one of the two characters remembers this problem and attempts to apply it to this situation. Since phones do not float in water, a modified version is proposed using mercury instead. The phone would certainly float on mercury, as it is a very dense liquid (the only metal that is liquid at room temperature). The extremely toxic nature of mercury makes pouring it into the air supply a very dangerous idea. Also the required amount of mercury would be extremely expensive. The weight of the mercury would also be substantial (13.5 kg/liter or 113 lb/gallon), and would likely break something in the air duct system. Both mercury and water could also push the phone further into the duct system instead of bringing it back. The end of the title text, declaring that the mercury idea would definitely make this situation better and not worse could be either a sarcastic commentary on these problems or a desperate attempt to bolster confidence that this extreme solution will work when everything else has failed. Given that Hairy was willing to sacrifice the phone anyway (by attempting to brick it), he would probably be better off pouring water down the vent—it wouldn't bring the phone within reach, but it would disable and thereby silence it (unless the phone is completely waterproof (and the waterproofing layer wasn’t damaged by the fall), which most phones aren't, especially those where the battery can be removed). Of course, Hairy probably wouldn't have gotten into this mess if he had not just been awakened brutally by a very loud alarm, making it difficult to think clearly (or, alternatively, if he just had a standard alarm clock that he could have unplugged or even a mechanical one that he could, say, hit with a hammer until it broke; or just flip the off switch). [The panel is completely black, with white text. Small lines indicate from where the two voices are coming, and also from where the alarm goes off. A small broken square surrounds the first word spoken.] Alarm: Bleep Bleep Voice (right): Urgh Voice (left): Your alarm is going off Voice (right): Huh? Voice (left): Make it stop. Voice (right) Urrgh [The panel is completely black, with white text. Small lines indicate from where the two voices are coming. Several small lines surrounds the last "sound" which is not spoken. The alarm noise is continued from the previous panel and continues over the top of the frame directly into the next panel.] Alarm: Bleep Bleep Bleep B Voice (left): Hit snooze. Voice (right): I'm trying . I closed the alarm app and I can't... I'll just pop out the battery. Voice (right): Whoops! Clang [The lights have turned on so it is now a white panel with black text. The voice to the right came from Hairy with morning hair. He is leaning over the side of the bed, looking down the air vent through which he has dropped the phone. The other person to the left is not shown. The alarm noise (now coming from the air vent as visualized by the lines coming out of the vent) still continues from the previous panel and continues over the top of the frame directly into the next panel.] Alarm: eep Bleep Bleep Ble Off-Screen voice: Make it stop! Hairy: It... fell down the vent. [Hairy is sitting in his bed with a laptop. The person to the left is still off-screen. The alarm noise still continues from the previous panel and continues over the top of the frame out of the comic the the right.] Alarm: ep Bleep Bleep Bleep Ble Off-Screen voice: Can you brick it remotely? Hairy: Trying... I think I fumbled it into airplane mode? Off-Screen voice: The battery could last for weeks. Hairy: You know, maybe we should just move. This comic follows a similar storyline to 349: Success and 530: I'm An Idiot , where Cueball , like Hairy here, encounters an issue and attempts progressively more absurd solutions. There is a callback to this in the title text of 1946: Hawaii .

Venus

Venus

https://www.xkcd.com/1519

https://www.explainxkcd.com/wiki/index.php/1519:_Venus

[Miss Lenhart is standing in front of an image depicting a section of a temperate Venus' surface, with greenhouses, grass, flowers and a river flowing into a sea.] Miss Lenhart: Venus was once temperate. It had seas and rivers, and Venusians cultivated vast fields of beautiful flowers. [The image now shows the entirety of Venus, with continents and oceans. The greenhouses appear to be fleeing from Venus.] Miss Lenhart: Until their greenhouses fled the planet due to the runaway greenhouse effect. [Miss Lenhart is shown to be standing in front of a classroom. Science Girl is sitting in the front row.] Miss Lenhart: The Venusians pursued their greenhouses to Earth, settling in the Netherlands and kickstarting the Dutch floral industry. Any questions? Off-panel student (presumably Science Girl): Because you're retiring in a month, do you just not care what you say anymore? Miss Lenhart: What?! I ride the skies atop a screaming bird of truth! Also, yes, I do not.

Miss Lenhart is teaching a class on science about the planet Venus . In the first panel, we see her teaching the history of Venus. Venus may have had water on its surface billions of years ago, but if that's true all hydrogen since then was eventually lost due to dissociation. However, there is no evidence that Venus ever had fields of flowers, or Venusians, or any other form of life. The runaway greenhouse effect on the second panel is a play on words. While the term normally refers to a rapid rise in temperature caused by greenhouse gases, Miss Lenhart uses the term literally and claims the existence of sentient greenhouses that actually ran away. In reality, the effect caused Venus to develop a thick atmosphere of carbon dioxide, which raised its temperature above to approx. 460 °C (860 °F), hotter than daytime on Mercury. This eventually destroyed all evidence of anything that had been on the surface of Venus billions of years ago. The third panel ties the previous distortion of Miss Lenhart into the very real historic reputation of the Netherlands as flower growers and as a further fabrication by Miss Lenhart the Dutch flower industry was in fact started by the Venusians. In the final panel we learn that she is a month away from retirement and doesn't care about relaying accurate information anymore. She just wants to have a laugh at the expense of the naive school children. Although it is clear that Science Girl in the front row was not fooled. The title text jokes about the butterfly effect , the idea that a butterfly flapping its wings in Japan can cause a Tornado in the U.S.. In this case the butterflies would just help pollinate the flowers. The butterfly effect is a term coined by Edward Norton Lorenz who had the comic 1350: Lorenz named after him due to its chaotic nature. Although Miss Lenhart was supposed to retire a month after this comic she seems to return a year later for a math course at university level, in 1724: Proofs , where she continues the trend from this class. It is probable that she retired from a primary or secondary school teaching position, likely to collect a pension, before taking a side job at a university/college level. [Miss Lenhart is standing in front of an image depicting a section of a temperate Venus' surface, with greenhouses, grass, flowers and a river flowing into a sea.] Miss Lenhart: Venus was once temperate. It had seas and rivers, and Venusians cultivated vast fields of beautiful flowers. [The image now shows the entirety of Venus, with continents and oceans. The greenhouses appear to be fleeing from Venus.] Miss Lenhart: Until their greenhouses fled the planet due to the runaway greenhouse effect. [Miss Lenhart is shown to be standing in front of a classroom. Science Girl is sitting in the front row.] Miss Lenhart: The Venusians pursued their greenhouses to Earth, settling in the Netherlands and kickstarting the Dutch floral industry. Any questions? Off-panel student (presumably Science Girl): Because you're retiring in a month, do you just not care what you say anymore? Miss Lenhart: What?! I ride the skies atop a screaming bird of truth! Also, yes, I do not.

Degree-Off

Degree-Off

https://www.xkcd.com/1520

https://www.explainxkcd.com/wiki/index.php/1520:_Degree-Off

[Hairy is acting as the host of a TV talk show, Degree-Off holding a microphone up. Cueball, a character who looks like a grown-up Science Girl, and Megan are acting as representatives of physics, biology and chemistry respectively. They each stand behind their own lectern with the respective subject label.] Hairy: Welcome to the Degree-Off , where we determine which field is the best! Physics, wanna go first? Cueball (Phys): Sure! I'd like to tell the story of Richard Feynman's Manhattan project lockpicking pranks... Labels: Phys Bio Chem [Zoom in so Megan is no longer visible. Cueball lifts his hand] Cueball (Phys): ...and as he said, "all science is either physics or stamp collecting." Cueball (Phys): Thank you. Hairy: Great! Bio, you wanna go next? Grown-Up Science Girl (Bio): Okay. Labels: Phys Bio [Zoom in on Grown-Up Science Girl so only she and her lectern are shown. A graph is shown above her. There us a label for the y-axis to the left of the axis which has four ticks with numbers. The x-axis is a timeline without ticks but three years indicating the start center and end of the axis. The graph shows a curve falling off, with one great spike up around 1920.] Y-axis label: Per 100,000 Y-axis: 800 600 400 200 X-axis: 1900 1950 2000 GUSG (Bio): This is a graph of the death rate from infectious disease in this country. Labels: Bio [Zoom back to original scene with Hairy holding the microphone down and Grown-Up Science Girl raising her left hand, while Cueball looks at her.] GUSG (Bio): The heroes of my field have slain one of the four horsemen of the apocalypse. Labels: Phys Bio Chem [Zoom in on only Cueball and Grown-Up Science Girl who is pointing aggressively at Cueball who leans away from her one hand on his lectern for support.] GUSG (Bio): While the heroes of your field gathered in the desert to create a new one. Labels: Phys Bio [Zoom back to previous scene all are holding their hands down.] Cueball (Phys): ...Jeez, what the hell? I thought this was supposed to be fun and lighthearted! GUSG (Bio): You must have been thinking of stamp collecting. Labels: Phys Bio Chem

Cueball (physics), a grown-up Science Girl (biology), and Megan (chemistry) appear to be on a talk show called Degree-Off, hosted by Hairy , where representatives of different fields, try to explain why their field is the best and why to get a degree in their field. The title "Degree-Off" is a portmanteau of " degree ", as in the recognized completion of studies at a school or university, and " face-off ", a direct confrontation between two people or groups. Since there are three participants, this is not a true face-off, unless Megan, who does not speak, is not counted. The host asks the physicist Cueball to go first. He light-heartedly begins to tell what appears to be long story, beginning with a Richard Feynman anecdote. During the Manhattan Project in Los Alamos, Richard Feynman got bored because of the isolation and started learning lock picking on the secret documents safes. Using these new skills, he played lots of pranks on his colleagues, like leaving notes and spooking them into believing there was a spy among them (which, of course, there was ). He finishes his case with a quote from Ernest Rutherford , implying that his speech was quite long and winding. The quote communicates the idea that physics is the only fundamental framework, so that the job of chemists, biologists and other scientist simply is to catalog and systematize observations ("collect stamps") on phenomena too complicated to presently be fully described in terms of physics. This idea was earlier lampooned by Randall in 435: Purity (and is also stated in the title text of 1158: Rubber Sheet ). The biologist goes next, showing with a graph (see below) that the field of biology has helped reduce disease. She then goes on to claim that the heroes in biology (the part known as Medicine) have even " slain " one of the Four Horsemen of the Apocalypse . Different traditions designate the Four Horsemen differently, but it is common for their number to include Plague or Pestilence. Science Girl claims that the field of biology has eliminated widespread Pestilence - at the time of writing it was not readily apparent that the old dog still has some teeth (although the rate of death from infectious disease in 2020–21 is still less than 200 per 100 thousand, far lower than the early 20th century). The imagery of Pestilence being thwarted by modern medicine was also used in the book Good Omens , by Terry Pratchett (of whom Randall is a fan, see 1498: Terry Pratchett ) and Neil Gaiman , where Pestilence has retired after the discovery of Penicillin , and been replaced by Pollution . The graph shows the death rate from infectious disease in the USA with the range of 1900-2000. The spike is attributable to the 1918 flu pandemic . It has been published in the paper Trends in Infectious Disease Mortality in the United States During the 20th Century . Science Girl then goes on to directly accuse Cueball (i.e. physicists) of creating a new Horseman to replace the one slain by the biologists. She refers to the development of the atomic bomb , which was built and tested in the New Mexico desert . The new horseman is therefore the atomic bomb, or the various perils associated with it. Science Girl's implied condemnation of the physics community has been echoed by some of the scientists involved in the project itself. After the test detonation of the first nuclear weapon on July 16, 1945, J. Robert Oppenheimer , the director of the Los Alamos National Laboratory , found himself quoting the Bhagavad Gita : "Now I am become Death, the destroyer of worlds." This harsh moral judgement shocks Cueball, who exclaims "I thought this was supposed to be fun and lighthearted!" While the set-up is of a frivolous friendly competition, Science Girl's presentation is surprisingly dark. Her retort in the final panel reveals that she was angered by the off-hand dismissal of 'soft' sciences as "stamp-collecting", and turned the game from a light-hearted fun into something more serious. In the title text the biologist goes on to declare in All caps that she is surprised a physicist isn't "harder", after all their condescending towards the "squishy" sciences. The use of 'hard' and 'squishy' is a play on the colloquial division between the so-called 'hard' sciences (such as physics and chemistry) and 'soft' sciences (such as biology and geology). 'Hard' sciences usually refer to the perception that in fields like physics, precisely repeatable experiments and measurements are possible, as opposed to 'soft' sciences seen as placing less emphasis on precisely quantifiable predictability - however Science Girl is extending 'hard' to its meaning of 'stoic', mocking Cueball for not being able to weather a personal moral attack. Again she is indicating that she's upset by directly referencing a mocking portrayal of other fields allegedly made by Cueball. To be fair to Cueball, the outbreak of disease is more a topic for epidemiology, and biology has spawned multiple diseases, atrocities, and bad movies. However, the Manhattan Project marked the first time in history that humanity possessed the ability to destroy itself - and shortly thereafter humanity got perilously close to doing so . In 520: Cuttlefish Randall shows that he personally respects biologists - or at least fears them. Within a year Randall has made several other comics about nuclear weapons, this one was the first of these the second, 1539: Planning , came out just 1½ month after this one and after that these two were released early in 2016: 1626: Judgment Day and 1655: Doomsday Clock . Nuclear weapons are also mentioned twice in Thing Explainer , specifically they are explained in the explanation for Machine for burning cities about thermonuclear bombs , but they are also mentioned in Boat that goes under the sea about a submarine that carries nukes. All three comics and both explanations in the book, does like this comic, comment on how insane it is that we have created enough firepower to obliterate Earth several times (or at least scourge it for any human life). [Hairy is acting as the host of a TV talk show, Degree-Off holding a microphone up. Cueball, a character who looks like a grown-up Science Girl, and Megan are acting as representatives of physics, biology and chemistry respectively. They each stand behind their own lectern with the respective subject label.] Hairy: Welcome to the Degree-Off , where we determine which field is the best! Physics, wanna go first? Cueball (Phys): Sure! I'd like to tell the story of Richard Feynman's Manhattan project lockpicking pranks... Labels: Phys Bio Chem [Zoom in so Megan is no longer visible. Cueball lifts his hand] Cueball (Phys): ...and as he said, "all science is either physics or stamp collecting." Cueball (Phys): Thank you. Hairy: Great! Bio, you wanna go next? Grown-Up Science Girl (Bio): Okay. Labels: Phys Bio [Zoom in on Grown-Up Science Girl so only she and her lectern are shown. A graph is shown above her. There us a label for the y-axis to the left of the axis which has four ticks with numbers. The x-axis is a timeline without ticks but three years indicating the start center and end of the axis. The graph shows a curve falling off, with one great spike up around 1920.] Y-axis label: Per 100,000 Y-axis: 800 600 400 200 X-axis: 1900 1950 2000 GUSG (Bio): This is a graph of the death rate from infectious disease in this country. Labels: Bio [Zoom back to original scene with Hairy holding the microphone down and Grown-Up Science Girl raising her left hand, while Cueball looks at her.] GUSG (Bio): The heroes of my field have slain one of the four horsemen of the apocalypse. Labels: Phys Bio Chem [Zoom in on only Cueball and Grown-Up Science Girl who is pointing aggressively at Cueball who leans away from her one hand on his lectern for support.] GUSG (Bio): While the heroes of your field gathered in the desert to create a new one. Labels: Phys Bio [Zoom back to previous scene all are holding their hands down.] Cueball (Phys): ...Jeez, what the hell? I thought this was supposed to be fun and lighthearted! GUSG (Bio): You must have been thinking of stamp collecting. Labels: Phys Bio Chem

Sword in the Stone

Sword in the Stone

https://www.xkcd.com/1521

https://www.explainxkcd.com/wiki/index.php/1521:_Sword_in_the_Stone

[Megan walks up to a sword in a stone.] [Megan attempts to pull the sword out of the stone.] [A beam of light and music plays as she removes the sword.] [While standing with the swords a voice from the sky speaks in gray shaky letters:] Celestial voice: The Throne of England is yours [Megan takes out her smart phone and searches:] Wikipedia England [Megan reads on her phone.] [Megan starts to replace the sword back into the stone.]

In this comic, Megan pulls a sword out of a stone. A flash of light comes down and music plays, and a heavenly voice tells her she has ascended to the throne of England . Megan then pulls out her phone and searches on Wikipedia for England . After having read for a while she begins, while reading on, to replace the sword into the rock. The comic references the fables of King Arthur and the Knights of the Round Table . In Arthurian legend, whoever can remove The Sword in the Stone is the lawful king of Britain (although this comic, as some versions of the legend, refers incorrectly to England). Arthur is an orphan being raised in secret; he notices the sword, removes it, and is proclaimed king. The sword is sometimes identified as Excalibur , although in other versions Excalibur was acquired by King Arthur from the Lady of the Lake . The most familiar version of this story is The Sword in the Stone by T. H. White which is based on Le Morte d'Arthur by Sir Thomas Malory . The animated musical by Walt Disney is a well-known version of this fairytale based on White's book. A key element in the joke is that as Megan begins to read about England, especially information concerning being an English ruler, she quickly thinks better of this and begins to put the sword back in its place. The punchline that Megan puts the sword back after reading about England suggests that the "gift" of being the leader of England is not worth the risk and/or work associate. British history is rife with monarchic strife, and a brief inquiry into their causes of death will show that almost one in three British rulers have died either in battle or from murder, etc. This would quickly lead most sane people to conclude that the risks associated with ruling England far outweigh the benefits. The title text furthers this plot, having Megan comment on the hassle when the only thing she was interested in was the cool sword. Apparently, Megan is not enthusiastic about power, and her choice is made when she sees how problematic it could be to reign over the country of England. There is also a subtle play on the fact that in the T. H. White version, Arthur likewise is unaware of the significance of pulling the sword from the stone - he is simply looking for a sword to replace the one belonging to his step-brother Kay that was stolen under his watch, to avoid embarrassment and reproach. From the time of the Roman Empire all the way up to Charles II's reclamation of the throne, the area now known as England has seen several migration waves, Viking raids, invasions and fierce power struggles among aristocratic families. Besides the constant threat of usurpation, as evidenced by the numerous wars for the crown, such as the Norman conquest and the War of the Roses , there were also constant difficulties in managing the frontier regions. This can be seen from Hadrian's Wall , a creation of the titular Roman Emperor designed to keep the ever difficult Scots out of the areas of Roman control (the Scots would be a constant problem for England up until the reign of King James VI and I ; think of the movie Braveheart for a good example of the regular headaches they caused, seen from the English point of view), as well as the Welsh uprisings that occurred with such consistency that you could set your watch by them. It is worth emphasizing that the term "England" is anachronistic in this context. At the time Arthur supposedly existed, there was no England — England was formed by Germanic tribes who settled in Britain between the fifth and seventh centuries . In many of the stories, including the earliest, Arthur was in fact depicted as a leader of the native Romano-Britons in their attempts to repel these invaders. England would not exist had Arthur succeeded. The anachronism is not new; it entered Arthurian legend in the Middle Ages. (Thomas Malory's Le Morte d'Arthur , for example, refers to Arthur as King of England.) In Arthurian legend, it was stated that Arthur would return when needed (in some versions he was explicitly associated with the Mab Darogan , a Welsh Messianic figure who would finally drive the English out of Britain and reclaim it for the native Britons). It is possible that Megan in this comic is a 21st-century reincarnation of Arthur. The timing of this comic might relate to the birth of princess Charlotte Elizabeth Diana on May 2, 2015, just four days before this comic, and the burden of a royal of having a whole life in public shaking hands of strangers. Since 2013 the line of succession was changed to absolute primogeniture , meaning that she will keep her current position in the line (4th after her older brother ) even if she later gets baby brothers. Before this year, that would not have been the case, as the male gender took rank over birth order. It is also probably not a coincidence that this comic was published the day before the UK General Election , occurring on May 7, 2015. This election decides the modern-day leader of the UK. And the problems they face today may even be more likely to cause Megan to give away the throne, than the risk of untimely death she would have faced in Arthur's days. A similar Wikipedia gag appears in 911: Magic School Bus . The sword in the stone also appears in 2578: Sword Pull . [Megan walks up to a sword in a stone.] [Megan attempts to pull the sword out of the stone.] [A beam of light and music plays as she removes the sword.] [While standing with the swords a voice from the sky speaks in gray shaky letters:] Celestial voice: The Throne of England is yours [Megan takes out her smart phone and searches:] Wikipedia England [Megan reads on her phone.] [Megan starts to replace the sword back into the stone.]

Astronomy

Astronomy

https://www.xkcd.com/1522

https://www.explainxkcd.com/wiki/index.php/1522:_Astronomy

[In front of a starry black sky, Megan looks at the stars through a telescope about twice her size, touching it at the base. She remains in the exact same position through all four panels.] [Beret Guy enters the panel holding a ladder and a magnifying glass.] [Beret Guy places the ladder next to Megan and her telescope. The ladder is stands like a triangle, is slightly larger than Megan, but smaller than the telescope.] [Beret guy climbs to the top of the ladder, and looks at the stars through a magnifying glass.] Usually, however, Beret Guy has strange powers , so it's quite possible that his method would yield similar or even better results than Megan's approach; see for instance 1490: Atoms . Given his naivety, it's also possible he just doesn't realize they should look any different. His naivety of astronomy is demonstrated in 811: Starlight . The history of astronomy is filled with drastic misunderstanding of distances to celestial bodies, even up to the present day like Randall has covered in 1342: Ancient Stars . Thus, the comic could be in reference to the general overestimation of distances, albeit taken to the opposite extreme.

For objects at a great distance one can achieve a better view by using a telescope as it is the typical method in Astronomy . Looking through a lens or a microscope in biology and other disciplines does magnify short distant objects. And a magnifying glass works more like a microscope when your eye lense is close to the focus of the magnifying glass, but when looking at distant objects you have to increase the distance between the glass and your eye where the focal length of your magnifying glass must be increased to meters instead of centimeters or less on a close view. But in general a Galilean Telescope works at the same principle as a magnifying glass together with your eye lens, the magnifying glass only has to have a long focal length which is optimized for far distances. In the comic, the objects being viewed by Megan could be stars , galaxies and the planets of our Solar System . Megan is using a telescope. Beret Guy attempts to view them using a step-ladder to get closer to the stars, and then looking at them through his simple hand-held magnifying glass. This approach could be successful only if the stars were a few meters away, so that the ladder would take him within a few centimeters of the study object. In fact the visible stars are several light years away (typically 18-20 orders of magnitude further away) and getting two meters up on a ladder won't make any perceivable difference. [ citation needed ] The title text assumes (for comic effect) that the only thing wrong with Beret Guy's strategy is the instability of the ladder endangering the expensive microscopes used by biologists for Astrobiology . Astrobiology is the study of life (or the possibility thereof) elsewhere in the universe, and here it would be either the planets and moons in our Solar System or exoplanets they needed to look at. This is the second comic related to studying exoplanets in two weeks, the first being 1517: Spectroscopy (see more references there). Since we cannot go there, they do, of course, not use any microscopes in the direct studies. However, one typical magnifier in biology is the electron microscope , used to study microbiology , and they cost a lot and are very heavy. It is therefore inadvisable to carry one up a ladder, and it could possibly become very expensive if you did try it anyway. [In front of a starry black sky, Megan looks at the stars through a telescope about twice her size, touching it at the base. She remains in the exact same position through all four panels.] [Beret Guy enters the panel holding a ladder and a magnifying glass.] [Beret Guy places the ladder next to Megan and her telescope. The ladder is stands like a triangle, is slightly larger than Megan, but smaller than the telescope.] [Beret guy climbs to the top of the ladder, and looks at the stars through a magnifying glass.] Usually, however, Beret Guy has strange powers , so it's quite possible that his method would yield similar or even better results than Megan's approach; see for instance 1490: Atoms . Given his naivety, it's also possible he just doesn't realize they should look any different. His naivety of astronomy is demonstrated in 811: Starlight . The history of astronomy is filled with drastic misunderstanding of distances to celestial bodies, even up to the present day like Randall has covered in 1342: Ancient Stars . Thus, the comic could be in reference to the general overestimation of distances, albeit taken to the opposite extreme.

Microdrones

Microdrones

https://www.xkcd.com/1523

https://www.explainxkcd.com/wiki/index.php/1523:_Microdrones

[Cueball is standing behind Megan who sits at a desk typing on her laptop.] Cueball: So how do we regulate all these micro drones? Cueball: I mean, Amazon delivery bots sound cool... [Cueball stands alone surrounded by three micro drones.] Cueball: But I worry that overnight we'll realize we're surrounded by these things, no one will know who's controlling them, and then bam , sci-fi dystopia. [Megan turns in her chair towards Cueball.] Megan: If you wanna slow it down, why not just remove all regulations, but then make drone theft legal? [Cueball takes his hand to his chin and Megan turns back to type on the laptop.] Cueball: ...I like that. Megan: You write to congress. Megan: I'll stock up on butterfly nets.

Amazon Prime Air is a conceptual drone -based delivery system currently in development by Amazon.com. While on one level he thinks the idea is cool, Cueball worries about living in a sci-fi dystopia, with those drones flying all around him, tracking his actions, etc. In the third panel, Megan suggests sending a message to Congress, suggesting a law for making the stealing of drones legal. This would alleviate the problem of drones flying around everywhere because if they did people would catch them to use for themselves. In the final panel Megan begins to search for butterfly nets so they are ready to catch the microdrones when the law to make it legal to steal the drones goes through. This tactic may not work as well as planned; drones will likely simply fly higher or employ other security measures since there are no regulations on drone behavior. The title text suggests one of five things: Amazon drones is also the subject of the title text in 1625: Substitutions 2 and there are two quadcopters over the volcano lake in 1608: Hoverboard . Also, Cueball is abducted by seemly sentient drones in 1630: Quadcopter . [Cueball is standing behind Megan who sits at a desk typing on her laptop.] Cueball: So how do we regulate all these micro drones? Cueball: I mean, Amazon delivery bots sound cool... [Cueball stands alone surrounded by three micro drones.] Cueball: But I worry that overnight we'll realize we're surrounded by these things, no one will know who's controlling them, and then bam , sci-fi dystopia. [Megan turns in her chair towards Cueball.] Megan: If you wanna slow it down, why not just remove all regulations, but then make drone theft legal? [Cueball takes his hand to his chin and Megan turns back to type on the laptop.] Cueball: ...I like that. Megan: You write to congress. Megan: I'll stock up on butterfly nets.

Dimensions

Dimensions

https://www.xkcd.com/1524

https://www.explainxkcd.com/wiki/index.php/1524:_Dimensions

[Cueball is sitting up against a tree, Megan lies with her hands behind her neck in front him under the foliage of the tree.] Cueball: Of the four dimensions I could have spent my life being pushed inexorably forward through, I guess "time" isn't the worst. Interestingly, Randall has already, back in the December 2014 issue of Wired magazine, published the xkcd guide to dimensions where the main part of this comic was already used in panel 9 out of 20. This issue of Wired magazine was about multiple dimensions, and Randall's section is about imagining higher dimension. The article is a mix of xkcd-style comics and captions explaining them. The panel in question show Cueball saying, "Of all the dimensions I could have spent my life being pushed inexorably through, I guess "time" isn't the worst." (the only difference being that "all the" has been changed to "the four" in this comic). In panel 15 of the Wired comic series, Randall considers how dimensions can be represented in a two-dimensional comic strip: a character moving within a panel represents movement in space but movement from panel to panel represents movement in time.

This cartoon is a romantic musing about time, and how even though we may not always realize it the progression of time is one of the better things in life. To accurately describe the world requires at minimum three spatial dimensions and the fourth dimension, time. The spatial dimensions don't necessarily have to be the familiar Cartesian system (Forward/backward, Right/Left, Up/Down), but can be described in many ways (like the spherical or cylindrical system). In spite of the fact that we are being pushed around the universe by being on Earth, we can exercise some control over these spatial dimensions by moving, and therefore our trajectory through these dimensions is not inexorable (impossible to stop). As we only can go one direction in time and have no way of changing the speed, we also are figuratively being pushed through time, and this movement is inexorable. Cueball sits under a tree un-moving with Megan simply enjoying the passage of time and says, "Of the four dimensions I could have spent my life being pushed inexorably forward through, I guess "time" isn't the worst." All of this amounts to an unusually erudite way for Cueball to say he feels content with how his life has turned out, despite the natural doubts one has as they get older. In the title text, Cueball then continues to muse about his favorite dimensions and places time in his top three dimensions. This means that one of the three spatial dimensions must be his least favorite. Though it is impossible to determine how he defines his favorite dimensions, as dimensions can be defined somewhat arbitrarily, they likely are length, height, and time as comics only use these three (time being represented by panels). Since rising steadily and digging downward are both pretty lethal, one could assume that Randall's least favorite dimension is up/down. (See also the one of my favorite halves comment in 1556: The Sky ) This could also be a reference to 1190: Time . Previously Randall has made a comic about a man who was pushed sideways — so he was pushed both through time and fell sideways: 417: The Man Who Fell Sideways . [Cueball is sitting up against a tree, Megan lies with her hands behind her neck in front him under the foliage of the tree.] Cueball: Of the four dimensions I could have spent my life being pushed inexorably forward through, I guess "time" isn't the worst. Interestingly, Randall has already, back in the December 2014 issue of Wired magazine, published the xkcd guide to dimensions where the main part of this comic was already used in panel 9 out of 20. This issue of Wired magazine was about multiple dimensions, and Randall's section is about imagining higher dimension. The article is a mix of xkcd-style comics and captions explaining them. The panel in question show Cueball saying, "Of all the dimensions I could have spent my life being pushed inexorably through, I guess "time" isn't the worst." (the only difference being that "all the" has been changed to "the four" in this comic). In panel 15 of the Wired comic series, Randall considers how dimensions can be represented in a two-dimensional comic strip: a character moving within a panel represents movement in space but movement from panel to panel represents movement in time.

Emojic 8 Ball

https://www.xkcd.com/1525

https://www.explainxkcd.com/wiki/index.php/1525:_Emojic_8_Ball

[An image of a shiny black ball with a white circle forming a black window at its center. Above the image is a title where the number 8 is written in a black circle, making it look like an 8-ball.] Emojic 8 Ball [Below the title is an input field with a placeholder text in grayed out text:] How will I die? [Below is a gray submit button.] Ask [The Emojic 8 Ball is below the ask button. The text in the input field can be changed by the user before pressing the ask button. After the submit button is pressed, 1 to 3 emoji symbols appear in the black window, framed inside a light blue equilateral triangle with one end pointing straight up. Once this has been done once, then a link appears below the panel with this text: Permalink].

Emojic 8 Ball is a parody of the Magic 8-Ball using emoji instead of words. "Emojic" is a portmanteau of "emoji" and "magic". A real Magic 8 Ball is a toy designed to visually resemble a real pool ball , which responds to questions (posed as yes-or-no questions) asked of it, ostensibly by magic. The responses are provided through a window on one face that displays text phrases printed on a triangular shape as depicted in this comic. Vintage balls contained a die with multiple triangular facets suspended in a dark fluid, while modern balls feature an electronic screen. The ball in this comic provides responses in the form of graphical Unicode "text" (which this comic is suggesting are emoji ). It is possible that this may be commentary on the inclusion of such "meaningless" symbols into Unicode. Ask a question and get a meaningless reply, even more meaningless than the answers given by a Magic 8 Ball. It could also be commentary about the ambiguous nature of advice from fortune tellers, horoscopes, etc. Each emoji has an ambiguous meaning (for example, depending on context, the cow symbol 🐄 could refer to beef or farming). The interpretation has more to do with the person receiving the fortune than anything given by the so-called fortune reader. With the default question being "How will I die?", this may also be partially a reference to " Machine of Death ". This book from 2010 is a collection of short stories edited by amongst other Ryan North (of Dinosaur Comics ) mentioned here since the idea was based on one of his comics . Since Randall Munroe wrote one of the stories the reference is very likely. All the stories are based around a device, the "Machine of Death", that can predict, with 100% accuracy though generally with extreme ambiguity, how people die from a drop of their blood. In many of the stories very unusual deaths are predicted, often in a very literal way, but not so you know when or where you will die. From the official home page the entire book can be downloaded for free as a PDF file (broken) 2020/06 archive.org copy . (Randall's story begins on page 421 - or page 218 of the two sided PDF file. It is simply called "?"). The "Machine of Death" may also have been referenced in the fourth panel of 1341: Types of Editors . Emoji were previously referenced in 1513: Code Quality . Emoji has since then become a recurrent theme on xkcd. But this is the first one with Emoji in the title. Note: if you see mostly squares (possibly with six numbers/letters inside) in the 8 Ball instead of actual symbols or pictures, it means your system doesn't have fonts that support the Emoji unicode characters. Scroll down to the discussion section below for suggestions on how to get and install the right font for your system, as well as to see a list of emoji characters so you can easily see if they're working or not. [An image of a shiny black ball with a white circle forming a black window at its center. Above the image is a title where the number 8 is written in a black circle, making it look like an 8-ball.] Emojic 8 Ball [Below the title is an input field with a placeholder text in grayed out text:] How will I die? [Below is a gray submit button.] Ask [The Emojic 8 Ball is below the ask button. The text in the input field can be changed by the user before pressing the ask button. After the submit button is pressed, 1 to 3 emoji symbols appear in the black window, framed inside a light blue equilateral triangle with one end pointing straight up. Once this has been done once, then a link appears below the panel with this text: Permalink].

Placebo Blocker

Placebo Blocker

https://www.xkcd.com/1526

https://www.explainxkcd.com/wiki/index.php/1526:_Placebo_Blocker

[Hairbun is standing in front of Cueball who does all the talking. Below them is a footnote.] Cueball: Some researchers* are starting to figure out the mechanism behind the placebo effect. Cueball: We've used their work to create a new drug: A placebo effect blocker . Footnote: * Hall et al, DOI: 10.1016/J.MOLMED.2015.02.009 [Zoom in on Cueball who now holds his arms out.] Cueball: Now we just need to run a trial! We'll get two groups, give them both placebos, then give one the real placebo blocker, and the other a... Cueball: ...wait. [Hairbun holds her chin, while Cueball just stand there for a beat panel.] [Hairbun looks again at Cueball who begins to take the lid off of a medicine bottle.] Hairbun: ...My head hurts. Cueball: Mine too. Cueball: Here, want a sugar pill?

This comic is a joke about the difficulty of testing a drug that is supposed to block the placebo effect. A placebo experiment is used for testing a drug candidate. It has two groups: one that gets a real drug candidate, and one that gets a fake. The placebo effect describes the observation that the group that gets the fake often show signs of having received a working drug - though commonly weaker than in the group that gets an effective real drug. Cueball states to Hairbun , with a citation from the real world, that his team created a Placebo Blocker, a drug designed to prevent the placebo effect. Cueball begins to design a test for this new drug. Following typical experimental design, patients would be split into two groups: a control group, and the group that receives the treatment. Cueball knows that the treatment given to the control group is supposed to be designed so that it is not influenced by the variable trying to be isolated. As the placebo effect is the effect under investigation, a placebo can not be used as a control treatment as a comparison with a placebo blocker. Cueball tries to design around this. In his test, both groups would receive a placebo as a treatment for an unspecified condition (the Treatment Placebo ); in addition the test group would receive the Placebo Blocker drug, while the control group would get a placebo pill instead (the Placebo-Blocker Placebo ). If this works as expected, the Treatment Placebo would be blocked by the Placebo Blocker in the test group, while in the control group, the Placebo-Blocker Placebo may have a placebo effect in blocking the placebo effect of the Treatment Placebo , and the difference between these effects can be measured to test the effectiveness of the Placebo Blocker . Cueball and Hairbun think about this trial until they both develop headache from frustration. Cueball then kindly offers Hairbun a sugar pill. While this might have helped cure the headache via the placebo effect had he told her it was a headache treatment, by revealing the pill as merely a sugar pill, it may reduce the effect (though it has been shown that placebos tend to work even if the subject is aware that they are placebos). In the title text, Cueball mentions that his sugar pills against headache works even better together with the new experimental placebo boosters . Incidentally, he indicates that he keeps those in the same bottle with his sugar pills. Assuming someone believes placebo boosters are in the jar this would allow them to take the sugar pills and receive a greater placebo effect, as the placebo effect is based upon faith in the treatment, regardless of whether there are placebo boosters in the jar. It is possible but unlikely that: Questionable neuroscience research is also discussed in 1453: fMRI . The placebo effect refers to the phenomenon in which patients given an inactive treatment such as a sugar pill can still show improvement relative to an untreated patient. The placebo effect is thus very important to consider when testing new drugs, since even ineffective drugs can have a positive effect on the patients due to the placebo effect. Modern drug experiments are hence conducted as double-blind trials , where the patients are randomly given either the treatment or a placebo without either they or the administering doctors knowing who receives the new drug and who received the placebo pill. (It is important that the doctor does not know, as if they did, it may affect the way they interact with the patient.) Generally the patients need to believe that they are receiving an active treatment, but one study showed that the effect can occur even if the patients are told that they are receiving a placebo pill. The key factor seems to be that the patients must believe that a positive effect will occur. For example, (1) patients experience a greater effect if they believe that the treatment is expensive and (2) patients who know that they have not been given an active treatment will experience the effect if they are told that placebos can have a positive effect through the power of the mind. Furthermore, the placebo can increase the effectiveness of treatments which seem larger (this is why over-the-counter pain medication is often administered as two half-doses rather than just one full dose). Several reasons for the placebo effect have been proposed, from study artifacts - such as under-reporting of negative outcomes by patients who think they are being treated, to neurological explanations for how mental state can translate into physical outcomes. Placebo-blockers do actually already exist. A side-effect of the opiate antagonist Naloxone is that it blocks the placebo effect . It should be noted that placebo does not actually improve the objective condition, only the patient's subjective perception of it (i.e. the patients do not get better more than they randomly would, but the placebo makes them think they do). [ citation needed ] The placebo effect is one of the greatest mysteries in modern medicine. It is typically found that the placebo effect is an effective treatment in itself in addition to the effectiveness of drugs and other treatments, and it has been found to cause small improvements to cancer outcomes. In other cases such as pain relief, the placebo effect is claimed to be comparable with the effectiveness of the drug itself - but this is a misunderstanding: this is not evidence of placebo working, but of the drug not working . The comic refers to the recent study by Kathryn T. Hall, Joseph Loscalzo, and Ted J. Kaptchuk. (2015) Genetics and the placebo effect: the placebome. Trends in Mol Medicine. Volume 21, Issue 5, May 2015, Pages 285–294 - however, bear in mind that one has to treat studies very carefully Kaptchuk vs Placebo It is possible to test the placebo blocker using three groups: a test group who receive a placebo and a placebo blocker, a control group who receive a placebo but no blocker, and a second control group who receive no treatment whatsoever, as a lack of treatment is the variable that an actual placebo is designed to control for. Still it might be hard to determine if the pills are having a negative effect or blocking the placebo effect, so multiple trials with multiple illnesses may have to be carried out. [Hairbun is standing in front of Cueball who does all the talking. Below them is a footnote.] Cueball: Some researchers* are starting to figure out the mechanism behind the placebo effect. Cueball: We've used their work to create a new drug: A placebo effect blocker . Footnote: * Hall et al, DOI: 10.1016/J.MOLMED.2015.02.009 [Zoom in on Cueball who now holds his arms out.] Cueball: Now we just need to run a trial! We'll get two groups, give them both placebos, then give one the real placebo blocker, and the other a... Cueball: ...wait. [Hairbun holds her chin, while Cueball just stand there for a beat panel.] [Hairbun looks again at Cueball who begins to take the lid off of a medicine bottle.] Hairbun: ...My head hurts. Cueball: Mine too. Cueball: Here, want a sugar pill?

Humans

Humans

https://www.xkcd.com/1527

https://www.explainxkcd.com/wiki/index.php/1527:_Humans

[Two robots are hovering in mid-air in the comic; what appear to be their optical arrays are facing each other.] Robot 1: You know, new research suggests ancient human kings and queens were covered in colorful fabric. Robot 2: Ugh, I like movie humans more. Screaming pink warriors with metal crowns poking through the skin on their heads! Robot 2: Now they're, what, big pillows? Robot 2: Science ruins everything. It is worth noting that this comic was released a few weeks before the scheduled release of Jurassic World , a reboot of the Jurassic Park movie franchise. This new movie, while supposedly aware of recent advances in dinosaur research, still depicts dinosaurs as giant lizards without feathers. It seems likely that the robot's comment about "pink humans" is targeted at this movie, especially given Randall's many earlier references to Jurassic Park and his fear of velociraptors .

The comic is set in the future, with two hovering robots discussing ancient history, in particular the clothing styles of kings and queens of the now extinct human species. It appears that robot archeologists have long ago unearthed remains from one or more human civilizations, providing evidence to build a concept of what humans must have looked, acted and even sounded like. Recently they must have discovered or determined new evidence, which presumably indicates the wearing of colorful clothing by human monarchs. Until this occurred they had very little if any reason to believe that any humans wore clothing. Noting the previous knowledge that some humans had metal rings around their heads, they have drawn the conclusion that these formed a separate species "Human Kings" and the crown is a natural outgrowth of the skeleton. Alternatively, the narrative of the fictional, horned Star Wars villain Darth Maul may have somehow survived into the era of robot film and misinterpreted as describing a human, though Maul's skin is red, not pink. When dinosaur bones were first dug up, the idea that dinosaurs were scaly, reptilian-like creatures was developed with the information available at the time. In recent times, it's been discovered that most dinosaurs actually had feathers , and in well preserved specimens, often from the Jiufotang Formation in Northern China, feathers of various forms are clearly visible. As this runs counter to the widespread and long-held image of dinosaurs as dramatic reptiles, the public has been reluctant to accept this new discovery, especially as the addition of feathers often conjures up the image of a giant chicken. (See 1104: Feathers ). Had it been discovered that dinosaurs were in fact covered with 6-inch long razor tipped spikes, people may have accepted this immediately as it conforms to the stereotype of dinosaurs as killing machines. In the same way, the new information on kings and queens being covered in fabric runs counter to the movie inspired image that the robot on the right had about humans, picturing them as being pink warriors that could grow metal out of their heads. The head-metal image may have been inspired by the discovery of kings and queens buried or entombed with their crowns lying on top of their skulls - for example the Electress Palatine Anna Maria de'Medici . If the robot beings in this comic don't know enough about human anatomy, they may assume that the metal crown is a specialized part of the human skeleton. Shown at least some evidence pointing to the truth - that humans typically wore clothing, and that a monarch's crown is only a symbol worn atop the head and not part of their body - the robot is predictably disappointed. Humans wearing clothing reduces them, in its opinion, to "big pillows," much like dinosaurs with feathers reduces them from primal beasts to "big chickens." Something made of cloth (or covered in it), at least in this robot's mind, cannot be a significant actor in history. The robot fails to reason that, among other things, history was what it was, and its wanting things to have been a certain way does not make it so. In addition, just as the clothing-wearing human is more than a mere pillow, and would have held much fearsome power over the world, a feathered dinosaur is not necessarily merely a giant chicken, but is still a powerful killing machine. The title text references our failure to change the popular image of dinosaurs to reflect the way they truthfully once were. Randall jokingly suggests that we should apply the same "featherless is cooler" logic to popular images of bald eagles ( since they are modern dinosaurs ), and remove their feathers (only in depictions of them, presumably), leaving them entirely bald. He appears hopeful that such a direct comparison, using the national symbol of the US no less, would provoke the public to change its mind about how dinosaurs are viewed, since modern raptors (birds of prey) are typically viewed with awe and respect, and are not often associated with the "chicken" stereotype mentioned above. [Two robots are hovering in mid-air in the comic; what appear to be their optical arrays are facing each other.] Robot 1: You know, new research suggests ancient human kings and queens were covered in colorful fabric. Robot 2: Ugh, I like movie humans more. Screaming pink warriors with metal crowns poking through the skin on their heads! Robot 2: Now they're, what, big pillows? Robot 2: Science ruins everything. It is worth noting that this comic was released a few weeks before the scheduled release of Jurassic World , a reboot of the Jurassic Park movie franchise. This new movie, while supposedly aware of recent advances in dinosaur research, still depicts dinosaurs as giant lizards without feathers. It seems likely that the robot's comment about "pink humans" is targeted at this movie, especially given Randall's many earlier references to Jurassic Park and his fear of velociraptors .

Vodka

Vodka

https://www.xkcd.com/1528

https://www.explainxkcd.com/wiki/index.php/1528:_Vodka

[Ponytail and Megan sit together at a table with two small shot glasses on the table. Ponytail is imbibing from a large bottle, while Megan is cradling a relatively large glass.] Ponytail: Maybe this is the vodka talking, but: Ponytail: Hi! I'm made from potatoes!

Vodka is a distilled beverage composed primarily of water and ethanol, sometimes with traces of impurities and flavorings. Traditionally, vodka is made by the distillation of fermented cereal grains or potatoes , though some modern brands use other substances, such as fruits or sugar. When people use the phrase "maybe it's the [type of alcohol] talking", they usually mean that they are speaking under the influence of alcohol and are saying things they probably wouldn't say when sober . This is similar to the Latin saying " in vino veritas " - in wine there is truth. However, in this comic, it appears that the vodka itself is literally speaking through Ponytail to discuss its origin, potatoes in this case. Other comics in which things have been taken too literally include 1099: Tuesdays and 1364: Like I'm Five . In the title text the vodka is implying it can be made from many other things beside potatoes. Vodka can be manufactured from potatoes, grain, and most other plants. Most illegal distilled vodka is often made with whatever one has on hand. However, vodkas are often repeatedly distilled to remove the "foreshots" (the first few ounces of alcohol that drip from the condenser), the "heads" (the higher alcohols which are first to condense during distillation) and the "tails" (the lower fusel oils which are last to be distilled). Removal of these leaves a clear solution consisting almost entirely of ethanol and water. This is in contrast to other distilled beverages like whiskey , brandy and rum . In 1541: Voice Ponytail is again possessed by a non-human entity , or maybe she is just making pranks with Megan in both cases. [Ponytail and Megan sit together at a table with two small shot glasses on the table. Ponytail is imbibing from a large bottle, while Megan is cradling a relatively large glass.] Ponytail: Maybe this is the vodka talking, but: Ponytail: Hi! I'm made from potatoes!

Bracket

Bracket

https://www.xkcd.com/1529

https://www.explainxkcd.com/wiki/index.php/1529:_Bracket

[A tournament bracket. With the names listed in groups on the left-hand side and right-hand side as shown below. Within individual groups the names are ordered in match-ups, two, three or even four in the first match. The last name on the right, Beyoncé, is not even matched for first round. The winners goes on to the next match, but there are many that skips some of the matches up until the quarterfinals, so some need to win 5 matches to reach the quarterfinals, others only need to win 4 of 3, and Beyoncé only 2. After the first level, the match-ups are always between two names. The two sides join up in a final in the middle, where the winner of the left side has a place for the name below and the winner of the right a place for the name above a central rectangular frame with place for the winners name. Below the pairing in the first round matches are mentioned above each of the clear groupings of the bracket.] [These are paired two and two.] Louis Armstrong Neil Armstrong Lance Armstrong Stretch Armstrong [These are paired two and two.] Jeff Gordan Jeff Bridges Jeff Daniels Jack Daniels [These are paired two and two.] Orson Welles H.G. Wells George Orwell Wells Fargo [The first four, two, three and two are paired.] Kurt Russell Russell Brand Russell Crowe Russell Simmons Richard Simmons Gene Simmons Gene Hackman Hugh Jackman Alan Rickman Alan Parsons Alan Partridge [The first four, three and two are paired.] Jenny McCarthy Joseph McCarthy Eugene McCarthy Eugene V. Debs Gene Wilder Olivia Wilde Oscar Wilde Oscar De La Renta Oscar De La Hoya [These are paired two and two.] Jack Nicklaus Jack Nicholson Phil Mickelson Nicholas Nickelby [These are paired.] Ryan Adams Bryan Adams [These are paired.] Chubby Checker Fats Domino [These are paired two and two.] Colin Firth Colin Farrell Will Ferrell The Farrelly Brothers [These are paired.] Joseph Gordon-Levitt Jennifer Love Hewitt [These are paired two and two.] Danny Glover Donald Glover Donnie Wahlberg Mark Wahlberg Mark Ruffalo Mark Shuttleworth [The first three and two are paired.] Philip Pullman Bill Pullman Bill Paxton Bill Murray Dan Aykroyd [The first two, and then three times three are paired.] Ginger Rogers Fred Rogers|Mister/Fred Astaire/Rogers Mister Spock Doctor Spock Doctor Octopus Doctor Manhattan Doctor Strangelove Doctor Strange Dr. No The Doctor Cory Doctorow [These are paired two and two.] Jerry Lee Lewis Jerry Lewis Jenny Lewis Xeni Jardin [These are paired two and two.] Chris Evans Chris Hemsworth Chris Pine Chris Pratt [These are paired.] Shallots Scallops Scallions [These are paired.] Siouxie Sioux Suzanne Vega [These are paired.] Tom Arnold Arnold Palmer Amanda Palmer [These are paired two and two.] Wes Craven Wes Anderson Paul Thomas Anderson Poul Anderson [These are paired two and two.] Sir Walter Scott Sir Walter Raleigh Sir Francis Drake Frank Drake [The first three, two and two are paired.] Van Halen Van Morrison Van Wilder Robert Van Winkle Rip Van Winkle Rip Torn Natalie Imbruglia [The first four are paired two and two the last is the only one not paired.] The Body Shop Bath and Body Works Bed Bath and Beyond Beyond Thunderdome Beyoncé

A tournament bracket shows the planned series of matchups in a tournament. In this comic Randall has shown a plan for a tournament between a wide range of cultural icons, both real and fictional, based mostly on similarities in their names. Various Internet groups have speculated on who would win in a fight between characters from different films. It may be relevant that the film Batman v Superman: Dawn of Justice was soon to be released at the time the comic was made where the two eponymous superheroes , Batman and Superman , fight against each other. The individual starting pairings are generally based on common or similar given names or surnames. Some adjacent brackets are "segued" by someone like Jeff Daniels, who segues from a bracket of "Jeff"s into a bracket of "Daniels"es. The bracket itself is fairly arbitrary. Most initial matchups are pairs, although several are trios and there's a quadruplet in the Russels group, while a single entry, Beyoncé , is given a first- and second-round bye . Most of the participants in the tournament are people, with a few exceptions. Shallots (small onions), scallops (bivalve mollusks), and scallions (green onions) are similar sounding foods, therefore may be confusing for some individuals (perhaps including Randall ). The final grouping on the lower right of the bracket features a several retail stores and a film. The title text possibly refers to Dr. Dre , particularly as a reference to his 2001 song " Forgot About Dre ". Alternatively, the title text could simply be a reference to the large number of pop culture personas that include the word "Doctor", such as Doctor House , Dr. Oz , Dr. Phil , Dr. Watson , "Doc" Brown , Dr. Seuss , Dr Pepper , Doctor Doom , Dr. Zoidberg , Dr. Horrible 's Sing-Along Blog and many others . Another simpler explanation is that it would cause the reader to question "Doctor Who?" answering their own question, although this answer would be incorrect because The Doctor is already present. It could also be a reference to the dual meaning of "The Doctor," either he meant to include Time Lord from Doctor Who and forgot about the EMH from Voyager, or he remembered the EMH and forgot the Time Lord. The incentive for the comic may have been the French Open 2015 , which started on the day of the publication. The comic inspired several groups to play out versions of the bracket. One user-voting based match-up on twitter, XKCD Bracket , was featured by Randall on the xkcd home page, with a link at at the top of the website, although the account was not created by Randall. (The link was part of a "news" flash, the other was regarding his book based on 1133: Up Goer Five . See more on this news in that comics explanation). In the final match on July 29, Neil Armstrong defeated Mister Spock (see the complete bracket ). The link was removed sometimes before Monday, 10 August 2015, within two weeks of the final result being revealed. Later Randall has made one smaller but similar bracket in 1819: Sweet 16 , and then an interactive April fools' comics in 2019, with an even larger bracket for determining the best emoji in 2131: Emojidome . The bracket for this comic was shown with links from the comic during the matches. [A tournament bracket. With the names listed in groups on the left-hand side and right-hand side as shown below. Within individual groups the names are ordered in match-ups, two, three or even four in the first match. The last name on the right, Beyoncé, is not even matched for first round. The winners goes on to the next match, but there are many that skips some of the matches up until the quarterfinals, so some need to win 5 matches to reach the quarterfinals, others only need to win 4 of 3, and Beyoncé only 2. After the first level, the match-ups are always between two names. The two sides join up in a final in the middle, where the winner of the left side has a place for the name below and the winner of the right a place for the name above a central rectangular frame with place for the winners name. Below the pairing in the first round matches are mentioned above each of the clear groupings of the bracket.] [These are paired two and two.] Louis Armstrong Neil Armstrong Lance Armstrong Stretch Armstrong [These are paired two and two.] Jeff Gordan Jeff Bridges Jeff Daniels Jack Daniels [These are paired two and two.] Orson Welles H.G. Wells George Orwell Wells Fargo [The first four, two, three and two are paired.] Kurt Russell Russell Brand Russell Crowe Russell Simmons Richard Simmons Gene Simmons Gene Hackman Hugh Jackman Alan Rickman Alan Parsons Alan Partridge [The first four, three and two are paired.] Jenny McCarthy Joseph McCarthy Eugene McCarthy Eugene V. Debs Gene Wilder Olivia Wilde Oscar Wilde Oscar De La Renta Oscar De La Hoya [These are paired two and two.] Jack Nicklaus Jack Nicholson Phil Mickelson Nicholas Nickelby [These are paired.] Ryan Adams Bryan Adams [These are paired.] Chubby Checker Fats Domino [These are paired two and two.] Colin Firth Colin Farrell Will Ferrell The Farrelly Brothers [These are paired.] Joseph Gordon-Levitt Jennifer Love Hewitt [These are paired two and two.] Danny Glover Donald Glover Donnie Wahlberg Mark Wahlberg Mark Ruffalo Mark Shuttleworth [The first three and two are paired.] Philip Pullman Bill Pullman Bill Paxton Bill Murray Dan Aykroyd [The first two, and then three times three are paired.] Ginger Rogers Fred Rogers|Mister/Fred Astaire/Rogers Mister Spock Doctor Spock Doctor Octopus Doctor Manhattan Doctor Strangelove Doctor Strange Dr. No The Doctor Cory Doctorow [These are paired two and two.] Jerry Lee Lewis Jerry Lewis Jenny Lewis Xeni Jardin [These are paired two and two.] Chris Evans Chris Hemsworth Chris Pine Chris Pratt [These are paired.] Shallots Scallops Scallions [These are paired.] Siouxie Sioux Suzanne Vega [These are paired.] Tom Arnold Arnold Palmer Amanda Palmer [These are paired two and two.] Wes Craven Wes Anderson Paul Thomas Anderson Poul Anderson [These are paired two and two.] Sir Walter Scott Sir Walter Raleigh Sir Francis Drake Frank Drake [The first three, two and two are paired.] Van Halen Van Morrison Van Wilder Robert Van Winkle Rip Van Winkle Rip Torn Natalie Imbruglia [The first four are paired two and two the last is the only one not paired.] The Body Shop Bath and Body Works Bed Bath and Beyond Beyond Thunderdome Beyoncé

Keyboard Mash

Keyboard Mash

https://www.xkcd.com/1530

https://www.explainxkcd.com/wiki/index.php/1530:_Keyboard_Mash

[Cueball approaches his desktop computer, which has emitted a message seemingly from White Hat as it displays a picture of him.] New chat message [Below the chat log is shown with White Hat's comments on the left in gray frames and Cueball's comments to the right in white frames. The first post in a row from each person is labeled with their picture at the end of a small arrow in the frame]: White Hat: Can't sleep. Stupid dog keeps barking. White Hat: So frustrating. FJAFJKLDSKF7JKFDJ Cueball: Ugh, I'm sorry. Maybe you could... Cueball: ... Okay, wait. I have to ask. Cueball: How did you hit a "7" in the middle there? White Hat: Huh? White Hat: I was just randomly keyboard mashing. Cueball: Sorry, Right. White Hat: Anyway, Cueball: I know this is silly, but like... All your hands were clearly right on the home row. Cueball: I don't get how one finger could have stretched up to the "7". White Hat: Why do you always fixate on these bizarre details? Cueball: I don't know. Cueball: Sorry. White Hat: It's weird, is all. [Chat transcript continues above White Hat's laptop, as it started in the first panel over Cueball's computer. But now we see a human-sized spider suspended from the ceiling by web is using three of its legs to type on the laptop. Behind the spider, White Hat is suspended from the ceiling upside down, almost totally encased in spider web. He tries to speak. Between them, a chair has been knocked over onto its back.] Spider (as White Hat in the chat): I am a normal human typing with my human hands. Cueball (chat): Yeah, of course. I know. White Hat (speaking): Mmm!! Mmph!!!

Cueball is chatting with White Hat , who says he is frustrated because a barking dog is preventing him from sleeping and White Hat mashes the keyboard to show his frustration. Keyboard mashing is often used in this way where the user makes their hands spasm across the keyboard, creating a line of text that can be compared to an angry groan in real life. Cueball is about to give some advice, but is confused by a quirk in what White Hat typed. All the characters he typed (except one) were on the home row of the QWERTY keyboard, the row starting with the letters A, S, D, and F, in the middle of the keyboard. The letters A, S, D, F, J, K, and L (all from the home row) are scattered throughout the text, but there is a 7 (which comes from the numbers row, on top of the keyboard) in the middle of this text. Cueball, wonders how White Hat put a seven in there, because if White Hat was keyboard mashing and touched the 7 key, he likely would have hit any of the QWERTY row keys because of keyboard mashing hand spasms, but he didn't. All the other characters were on the home row. White Hat berates Cueball for always focusing on strange, tiny details. When the final panel shows what's going on where White Hat is, we see that a giant spider has imprisoned him in a web and is talking to Cueball, which explains how the keyboard mashing "White Hat" did was strange. The reason the dog was barking appears to be because the giant spider was lurking nearby. Little did White Hat know that the dog was alerting him of the spider. When the spider notices that White Hat mentions the barking dog to Cueball, the spider apparently restrains White Hat and takes over typing. Another possibility is that the "dog" barking is actually White Hat, as he is seen making grunts from beneath the spider's silk. It can be seen in the last panel that the spider is typing with 3 legs, which explains how the 7 key would have been pressed. The statement "I am a normal human typing with my human hands" is an oddly specific assertion from the giant spider that it is actually a human, a claim that would normally be taken for granted and had not really been cast into doubt by Cueball's inquiries about how "7" got into a string of home-row keystrokes. The title text invitation ends with a similar statement, suggesting that they "...CHAT ABOUT OUR INTERNAL SKELETONS", which spiders (unlike humans) do not possess and which are not a common conversation point among humans, helping to demonstrate (along with the spider's suspiciously specific denial and using the phrase cook bread instead of bake bread) that the spider is not very good at blending in as a human. This implies that the spider also wants to trap and possibly eat Cueball as well, or actually hang out with him in an attempt to make friends or to find out how humans talk so the spider will be able to blend in better in the future. "...HANG OUT INSIDE MY HOUSE" may also have a double meaning, as White Hat and the spider are actually "hanging" from the ceiling inside White Hat's house. Also another oddity is that the spider asks Cueball to cook bread, although bread is actually baked, and in any case this isn't a common pastime during the night (the spider could also mean make toast). The final oddity is that the title text is written in all caps which is usually interpreted as shouting and would not be used in a casual invitation, although the title text should just be imitating the fact that the rest of the text messages use a font that make them look like they are in all caps. The central theme of the comic is a vindication of Cueball's world-view, wherein tiny oddities such as the appearance of a numeral in a keyboard mash merit investigation. In the real world, the appearance of a "7" in the middle of a home row keyboard mash is more likely attributable to key ghosting . Alternatively, the fact that Cueball uses the phrase "all your hands" instead of "both your hands" or "both of your hands" could indicate that Cueball (and likely other people as part of a coordinated uprising of giant spiders) has also been taken hostage by a spider, and the spider behind Cueball's profile picture knows that the organism behind White Hat's profile picture is a spider, not a human. This would also explain why the spider behind White Hat's profile picture feels that the spider behind Cueball's profile picture pointing out the usage of a numeral among home row keys is weird; spiders know that other spiders have many legs and that these legs do not have to be in the same section of the keyboard. In the title text of 1541: Voice there is again a reference to a sentence that could be uttered correctly by a human, but would never be used in real life. But a non-human entity that tries to blend in as a human, may inadvertently use such a "wrong" sentence to try to ensure other people think they are indeed humans. It is a direct reference to the type of sentence used in the title text here. This comic is somewhat unusual in that the panels are read from top to bottom instead of being read from left to right in more than one row. This may be in order to accommodate the second panel, which must be tall due to containing a text conversation, without making the comic look weird due to the second panel being much taller than the first panel. [Cueball approaches his desktop computer, which has emitted a message seemingly from White Hat as it displays a picture of him.] New chat message [Below the chat log is shown with White Hat's comments on the left in gray frames and Cueball's comments to the right in white frames. The first post in a row from each person is labeled with their picture at the end of a small arrow in the frame]: White Hat: Can't sleep. Stupid dog keeps barking. White Hat: So frustrating. FJAFJKLDSKF7JKFDJ Cueball: Ugh, I'm sorry. Maybe you could... Cueball: ... Okay, wait. I have to ask. Cueball: How did you hit a "7" in the middle there? White Hat: Huh? White Hat: I was just randomly keyboard mashing. Cueball: Sorry, Right. White Hat: Anyway, Cueball: I know this is silly, but like... All your hands were clearly right on the home row. Cueball: I don't get how one finger could have stretched up to the "7". White Hat: Why do you always fixate on these bizarre details? Cueball: I don't know. Cueball: Sorry. White Hat: It's weird, is all. [Chat transcript continues above White Hat's laptop, as it started in the first panel over Cueball's computer. But now we see a human-sized spider suspended from the ceiling by web is using three of its legs to type on the laptop. Behind the spider, White Hat is suspended from the ceiling upside down, almost totally encased in spider web. He tries to speak. Between them, a chair has been knocked over onto its back.] Spider (as White Hat in the chat): I am a normal human typing with my human hands. Cueball (chat): Yeah, of course. I know. White Hat (speaking): Mmm!! Mmph!!!

The BDLPSWDKS Effect

The BDLPSWDKS Effect

https://www.xkcd.com/1531

https://www.explainxkcd.com/wiki/index.php/1531:_The_BDLPSWDKS_Effect

[Ponytail stands next to a screen displaying a firetruck hurtling toward Cueball on what appears to be a layer of gas.] Ponytail: The Bernoulli-Doppler-Leidenfrost-Peltzman-Sapir-Whorf-Dunning-Kruger-Stroop Effect states that if a speeding fire truck lifts off and hurtles towards you on a layer of superheated gas, you'll dive out of the way faster if the driver screams "red!" in a non -tonal language that has a word for "firefighter" than if they scream "green!" in a tonal language with no word for "firefighter" which you think you're fluent in but aren't .

The BDLPSWDKS Effect in the title is an acronym for Bernoulli-Doppler-Leidenfrost-Peltzman-Sapir-Whorf-Dunning-Kruger-Stroop Effect, as explained by Ponytail in the comic. She stands in front of a slide that shows Cueball being subjected to this effect. The effect mentioned appears to be a mashup of seven scientific principles (with nine scientists' names included) from physics and social sciences, with elements from each principle appearing in the resulting description of the effect: This comic is probably a comment on the "replication crisis" in social psychology which has been in the news recently . For example, studies finding that merely thinking about intelligent people (e.g., writing down the attributes of a professor) will actually improve performance on math tests were once widely believed, and this "intelligence priming" effect is even included in textbooks. However, recent attempts to reproduce these effects have mostly failed and this failure to replicate is true of many social priming effects as well as other experiments in social psychology. Randall is also mocking the complicated, or even convoluted, setups often used in these experiments. Usually, for an effect to be considered real, the scientific method requires the effect to be replicated by different experimenters in different times and places. It is hard to imagine several scientists in different parts of the world creating the setup to replicate this effect; however the title text mentions, sarcastically, that it has been done countless times. Many other xkcd strips have commented on the ease with which surprising and novel, but false, results can be published in the scientific literature, such as 1478: P-Values and 882: Significant . [Ponytail stands next to a screen displaying a firetruck hurtling toward Cueball on what appears to be a layer of gas.] Ponytail: The Bernoulli-Doppler-Leidenfrost-Peltzman-Sapir-Whorf-Dunning-Kruger-Stroop Effect states that if a speeding fire truck lifts off and hurtles towards you on a layer of superheated gas, you'll dive out of the way faster if the driver screams "red!" in a non -tonal language that has a word for "firefighter" than if they scream "green!" in a tonal language with no word for "firefighter" which you think you're fluent in but aren't .

New Horizons

New Horizons

https://www.xkcd.com/1532

https://www.explainxkcd.com/wiki/index.php/1532:_New_Horizons

[Cueball and Ponytail are standing in front of a large computer console. Cueball's hands are on the keyboard; both are looking at the screen.] Cueball: We made it! After all these years, New Horizons is finally revealing the surface of Pluto! Ponytail: Take that , Dawn team. [In the next four frames, we see photos, entirely black except for a circle in the middle. The circle is initially small, indistinct and appears in shades of grey. Successive circles are larger showing more color and shade variation. In the last, we see a blurry but recognizable outline of Africa, the Middle East and part of Western Asia, along with some clouds. The lighting pattern suggests that it is daytime in Africa, sometime in the northern summer.] [A close-up of the two at the console.] Cueball: OK, who did the calculations for the Jupiter slingshot maneuver? Ponytail: (facing away from the computer console) Dammit, Steve...

New Horizons is a NASA mission launched in 2006 to study the dwarf planet Pluto and its moons. Its closest approach to Pluto was on July 14, 2015 ( NASA countdown clock ), two weeks after the publication of this comic. In April and May 2015, it captured the first images of Pluto with enough resolution to see some details on Pluto's surface ( NASA photos from 12 April to 12 May ). These images are similar to the second panel of the comic, with Pluto shown as a gray dot only a few pixels wide. Dawn is a NASA mission launched in September 2007 to study the asteroid Vesta and dwarf planet Ceres . Its closest approach to Vesta began on July 16, 2011 by the Vesta approach , and entered orbit around Ceres on 6 March 2015. And in fact the pictures of Ceres are still in a much better resolution like in this comic 1476: Ceres , but these images are also still mysterious. On the day this comic was published, New Horizons was at 0.34 AU from Pluto and 32.55 AU from the Sun ( Johns Hopkins University's New Horizons page ). One Astronomical unit (AU) is the approximate distance of Earth from the Sun, or about 150 million kilometers. Distances from the Sun by semi-major axis : Vesta 2.36 AU; Ceres 2.77 AU; Jupiter 5.20 AU; Pluto 39.26 AU. A slingshot maneuver is a technique where a spacecraft is maneuvered or accelerated with the help of a gravitational field. In the comic, presumably someone named Steve made the calculations for the New Horizons spacecraft to accelerate toward Pluto using Jupiter 's gravity. In the first panel we see Cueball and Ponytail standing in front of a computer monitor and observing a series of images sent back from New Horizons as it approaches the planet. They are about to see the dwarf planet Pluto with the highest resolution ever. As the spacecraft gets closer, the images return... Earth . Steve had miscalculated the gravity assist and the spacecraft was about to crash into Earth. Because the spacecraft carries 10.9 kg (24 lb) of radioactive plutonium-238, a crash on Earth is extremely dangerous. It was estimated that a worst-case scenario of total dispersal of on-board plutonium during the launch would spread the equivalent radiation of 80% the average annual dosage in North America from background radiation over an area with a radius of 105 km (65 miles) ( Draft Environmental Impact Statement for the New Horizons Mission ). Because of decay during the flight, the situation would be slightly less dire if it crashed years later, but still a major disaster. Less importantly, this is a huge embarrassment, especially in front of the successful Dawn team, who were the first to get a probe to visit a dwarf planet. Part of the joke is the utter implausibility of such an error being made, and then not being detected. The title text suggests the team is considering crashing the probe into Steve's house as punishment for his errors. However, doing so would expose Steve's neighbors to potentially lethal levels of radiation. Therefore, the team would most likely have to crash the probe into an unpopulated area or the sea, to minimize human exposure. Randall described what might happen if New Horizons crashed into one's car in his what if? blog [1] , and assuming the car was parked in the driveway the house would be similarly affected by the blast. Luckily this was not what happened and when New Horizons reached Pluto 1½ month later Randall made this tribute to the achievement: 1551: Pluto and also on that day he released the first what if? in over three months, and it was called New Horizons . Randall has used a Steve in a similar context in 809: Los Alamos (set in 1945). If this is the same person, then 'Steve' would be at least 90 years old in 2015. A person named Steve also comes up with an inappropriate suggestion in 1672: Women on 20s . [Cueball and Ponytail are standing in front of a large computer console. Cueball's hands are on the keyboard; both are looking at the screen.] Cueball: We made it! After all these years, New Horizons is finally revealing the surface of Pluto! Ponytail: Take that , Dawn team. [In the next four frames, we see photos, entirely black except for a circle in the middle. The circle is initially small, indistinct and appears in shades of grey. Successive circles are larger showing more color and shade variation. In the last, we see a blurry but recognizable outline of Africa, the Middle East and part of Western Asia, along with some clouds. The lighting pattern suggests that it is daytime in Africa, sometime in the northern summer.] [A close-up of the two at the console.] Cueball: OK, who did the calculations for the Jupiter slingshot maneuver? Ponytail: (facing away from the computer console) Dammit, Steve...

Antique Factory

Antique Factory

https://www.xkcd.com/1533

https://www.explainxkcd.com/wiki/index.php/1533:_Antique_Factory

[Beret Guy is leaving with a briefcase in hand.] Beret Guy: Gotta go - I'm late for work. Off-screen voice: Oh, where are you working now? Beret Guy: Antique factory! [Beret Guy arrives in a room with a chair, a table, and a small cabinet. He pulls out the chair.] [Beret Guy sits in the chair. He has placed the briefcase behind the chair.] [Beat panel.]

Beret Guy has a new job with a paradoxical premise. When asked where he works, he says " Antique factory!" which is an oxymoron since one cannot build an antique object directly in a factory: Only when the item is old enough to be worth more than its original price (and will often have to have been in use during this time period), can it be called an antique. At the "factory", Beret Guy walks up to a chair, a table, and a small cabinet, then simply sits down in the chair and does nothing else. Of course, one does not simply make or manufacture antiques - instead, one must wait. Beret Guy appears to be doing exactly this. The implication is that the "antique factory" is simply a place where furniture is stored until it becomes old enough to be considered "antique", and that Beret Guy doesn't perform any useful function (except perhaps using the items to make them look old and worn, or keeping an eye on the inventory so it won't be stolen). The title text refers to allergy warning labels saying May contain nuts . More specifically, they may say "Manufactured in a facility which also processes nuts", "Manufactured on equipment that also processes nuts", or similar. These warnings indicate that bits of powder and oil from nuts may have been mixed into the product, creating a hazard to people with nut allergies. Sometimes these warnings are used for allergens besides nuts, but nuts are likely the most common. The joke here is that of course the time that has passed for a specific item to become an antique will be the same time that has also passed while elsewhere nuts have grown. Thus the time that has inexorably passed to make a specific item antique will also have processed nuts. Beret Guy has previously "traveled" into the future in 209: Kayak . He has also previously waited for a long amount of time in 1088: Five Years . [Beret Guy is leaving with a briefcase in hand.] Beret Guy: Gotta go - I'm late for work. Off-screen voice: Oh, where are you working now? Beret Guy: Antique factory! [Beret Guy arrives in a room with a chair, a table, and a small cabinet. He pulls out the chair.] [Beret Guy sits in the chair. He has placed the briefcase behind the chair.] [Beat panel.]

Beer

Beer

https://www.xkcd.com/1534

https://www.explainxkcd.com/wiki/index.php/1534:_Beer

[Cueball and Hairy standing in front of a fridge.] Hairy: What do you drink? Stouts? Lagers? Cueball: Uh, anything's fine. [Cueball and Hairy holding beers and Hairy is drinking.] Cueball: ...do you ever think maybe we should just admit that all beer tastes kind of bad and everyone's just pretending? [Now Cueball drinks.] Hairy: Man, you are no fun at all. Cueball: Ok, got it. Not a word. Hairy: Dude, if you don't like it, don't drink it. Cueball: No, no, gotta do my part! Mmmmm!!!

Hairy offers Cueball some beer from his fridge, and Cueball takes the opportunity to suggest that people should admit that beer tastes bad and stop pretending to like it. Hairy berates Cueball for making such an affirmation, and Cueball admits defeat, deciding to drink the beer anyway and pretend to like it to play his part in what he perceives to be a mass delusion. There are two possible interpretations of this comic. One is that Cueball is right and that no one really likes beer, and everyone is just pretending in order to fit in. The other is that Hairy actually likes beer, but Cueball fails to recognize that possibility, assumes Hairy is faking it, and plays along. In the case where Cueball is correct, the comic would imply that beer doesn't actually taste good, and people instead pretend to like beer to conform to social norms. The theory is that this pretense is perpetuated by advertising and peer pressure , which present beer as a naturally pleasant beverage. In this interpretation, Cueball, having failed to break the mutual knowledge barrier , admits defeat and joins Hairy in pretending to enjoy beer. The second case would mean that Cueball mistaken in assuming that nobody likes beer, either because he fails to empathize with those who have a different experience than his, or because he's heard from other people who also admitted not to like beer, and extrapolated that opinion to everyone (perhaps assuming that such admissions are underrepresented due to the cultural bias in favor of drinking ). The title text expands on Cueball's perspective, stating ( sarcastically ) that he feels no peer pressure to like beer. The pressure to drink beer or other alcoholic drinks is a well-known phenomenon, especially among adolescents and young adults . [Cueball and Hairy standing in front of a fridge.] Hairy: What do you drink? Stouts? Lagers? Cueball: Uh, anything's fine. [Cueball and Hairy holding beers and Hairy is drinking.] Cueball: ...do you ever think maybe we should just admit that all beer tastes kind of bad and everyone's just pretending? [Now Cueball drinks.] Hairy: Man, you are no fun at all. Cueball: Ok, got it. Not a word. Hairy: Dude, if you don't like it, don't drink it. Cueball: No, no, gotta do my part! Mmmmm!!!

Words for Pets

Words for Pets

https://www.xkcd.com/1535

https://www.explainxkcd.com/wiki/index.php/1535:_Words_for_Pets

[Caption above the frame:] Words I use to refer to a pet over the years I live with it: [Inside the box are four diagrams. Each diagram contains three elliptical sections containing the previous one, each section is drawn identical from diagram to diagram and they are labeled the same way from diagram to diagram. A fourth section (a red ellipse) moves from diagram to diagram and its label changes from diagram to diagram.] [The red section of the first diagram mainly overlaps the innermost section, but about a third of it is in the second section. The labels are written above the three white sections and then inside the red section. The labels from inside and out and last the label of the red section:] The pet's name Words related to the pet Coherent words of any kind First year [The red section of the second diagram mainly overlaps the right part of the second section, but it just touches both the first and the third section. The labels are written above the three white sections and then inside the red section. The labels from inside and out and last the label of the red section:] The pet's name Words related to the pet Coherent words of any kind Second year [The red section of the third diagram mainly overlaps the right part of the third section, but about a third of it is inside the second section and a small part is outside of the third section. The labels are written above the three white sections and then inside the red section. The labels from inside and out and last the label of the red section:] The pet's name Words related to the pet Coherent words of any kind Third year [The red section of the fourth diagram is completely outside the third section and has to be so far to the right, that the other sections has been moved from the center of the frame to the left. The labels are written above the three white sections and then inside the red section. The labels from inside and out and last the label of the red section:] The pet's name Words related to the pet Coherent words of any kind Fourth year onward

The comic shows four similar Euler diagrams , one for each of the first four years of living with a pet . The diagrams depict sets of words which have varying efficacy in actually identifying the pet, and each one shows how the words used by Randall to refer to his pet change year by year and becoming less and less specific as time goes on. In the first year it is dominated by the actual name of the pet or words closely related. For example, a dog named Lassie might be called either " Lassie ", "dog", "collie" or "boy/girl". Moving on to the second year, these related words like "dog" and "collie" get more abundant while the actual name is seldom used. Phrases such as "good dog" or "here, boy" are likely common. Giving a dog the name "Dog" is so common that there is a trope about that. In the third year, the pet's name is no longer used at all and the owner probably uses simple phrases like "come" or "come here" to call the pet, omitting the name. This is also probably referring to expletives. The fourth year entails the use of just any sound, not coherent words . This may be referring to something like baby talk , attempted mimicry of the pet's vocalizations, or whatever random sounds the owner has discovered that get a response from the pet. This development can be attributed to the fact that some animals don't listen to their own name but rather react to the sound of the voice of their owner. It could also refer to the growing bond between owner and the pet, as well as the effect described in 231: Cat Proximity . The title text suggests that the inevitable result of this continuing pattern is that by the seventh year, Randall will be communicating with the pet in its own language. This might refer to the tendency of some pet owners to mimic or imitate their pets' vocalizations, as if speaking to them. Alternatively, this could be interpreted as a joke that pets don't have proper language and the owner has degenerated to a lack of language themselves as time goes on. The title text and the caption makes it a little difficult to be certain if the comic refers to when you talk about your pet to other people ("my dog is always hungry") or when you call at it, which would be the only time it would make sense to use coherent words in the animal's own language - "Woof" = come here. [Caption above the frame:] Words I use to refer to a pet over the years I live with it: [Inside the box are four diagrams. Each diagram contains three elliptical sections containing the previous one, each section is drawn identical from diagram to diagram and they are labeled the same way from diagram to diagram. A fourth section (a red ellipse) moves from diagram to diagram and its label changes from diagram to diagram.] [The red section of the first diagram mainly overlaps the innermost section, but about a third of it is in the second section. The labels are written above the three white sections and then inside the red section. The labels from inside and out and last the label of the red section:] The pet's name Words related to the pet Coherent words of any kind First year [The red section of the second diagram mainly overlaps the right part of the second section, but it just touches both the first and the third section. The labels are written above the three white sections and then inside the red section. The labels from inside and out and last the label of the red section:] The pet's name Words related to the pet Coherent words of any kind Second year [The red section of the third diagram mainly overlaps the right part of the third section, but about a third of it is inside the second section and a small part is outside of the third section. The labels are written above the three white sections and then inside the red section. The labels from inside and out and last the label of the red section:] The pet's name Words related to the pet Coherent words of any kind Third year [The red section of the fourth diagram is completely outside the third section and has to be so far to the right, that the other sections has been moved from the center of the frame to the left. The labels are written above the three white sections and then inside the red section. The labels from inside and out and last the label of the red section:] The pet's name Words related to the pet Coherent words of any kind Fourth year onward

The Martian

The Martian

https://www.xkcd.com/1536

https://www.explainxkcd.com/wiki/index.php/1536:_The_Martian

[Cueball is sitting at a desk using a computer and White Hat walks in.] Cueball: Ooh, trailer for The Martian! White Hat: What's that? Cueball: Movie of a book I liked. White Hat: Should I read it? [Cueball pivots on chair and turns away from computer to face White Hat.] Cueball: Depends. You know the scene in Apollo 13 where the guy says "we have to figure out how to connect this thing to this thing using this table full of parts or the astronauts will all die? White Hat: Yeah? [Cueball pivots on chair again and resumes using computer while talking. White Hat looks at his smart phone.] Cueball: The Martian is for people who wish the whole movie had just been more of that scene. White Hat: How on earth did that become a big-budget thing with Matt Damon? Cueball: No idea, but I'm so excited. In a video interview by Adam Savage with Andy Weir the author of The Martian says that his goal was to make the whole book like the mentioned scene from Apollo 13 - exactly what the comic is saying. The video was posted on YouTube the day after the xkcd comic. In the end, The Martian likely didn't disappoint the big-budget movie makers, grossing more than $630 million against a budget of $108 million.

Cueball is very excited about seeing that the trailer for The Martian is finally released, because he really liked the book. Cueball most likely represents Randall himself in this comic. This trailer for The Martian was released on Monday, June 8, 2015, two days before this comic, although a teaser "viral" trailer had been released the previous day. The film, starring Matt Damon ( The Bourne Identity ), is directed by Ridley Scott ( Alien ). It was released in the United States on October 2, 2015. The Martian is based on a book of the same name by Andy Weir . The book is very popular among nerds. The plot is ­a cross between the film Apollo 13 and the plot of the novel Robinson Crusoe — but just on Mars . Cueball is telling White Hat about this trailer and the book, thus White Hat asks if he should read it. Cueball then describes a scene from Apollo 13: You know the scene in Apollo 13 where the guy says "we have to figure out how to connect this thing to this thing using this table full of parts or the astronauts will all die?" And he then tells White Hat that The Martian is like that the whole way through. What is actually said in the mentioned scene is: We gotta find a way to make this fit into the hole for this using nothing but that. The first part being a large square box and the other a smaller cylinder. The film Apollo 13 is based on the true historical event of the Apollo 13 incident where the astronauts find themselves in a damaged spacecraft. They evacuated from the Apollo Command Module , losing all its life support systems, to the Lunar Module which was designed only for two people for two days instead of three people for four days. One issue the crew faced was a buildup of carbon dioxide. In order to resolve the issue, the crew needed to find a way to attach a square-shaped air-cleaning cartridge from the command module to the circular receptacle of the lunar module: literally fitting a square peg into a round hole. In one brief scene , the Mission Control staff gather together a box of items equivalent to what the crew would also have on-board and sit down with the mandate to figure out how the astronauts can connect the two with the items available to them. In that case, the ground crew took on the task of trial and error given the availability of backup supplies in case they damaged or destroyed some of the supplies. Once a working solution was devised, specific instructions were relayed to the astronauts. Cueball suggests that The Martian essentially consists primarily of the type of problem-solving shown in that scene (as was suggested by the author, Andy Weir, in this interview). The Apollo 13 scene is actually referenced in the book, when the Matt Damon character says "CO2 isn't a problem. (...) All systems use standard filters (Apollo 13 taught us important lessons)." In the final panel, White Hat, who probably would not be so interested in this kind of story, wonders how a novel based on that kind of seemingly cerebral and procedural problem-solving became a big-budget film starring Damon. Big-budget films are generally films with a great deal of special effects and often also action sequences likely to draw big audiences — and to gain big returns. Matt Damon has become a high-profile big-budget star known for action films like the Bourne film series . On the day the movie was released in the US, Randall went to see it and released this comic about it: 1585: Similarities . In 2561: Moonfall a similar discussion of an upcoming movie is made for Moonfall . But in that case it is the scientific inaccuracy that is the subject, and the huge explosion that makes it worth seeing anyway... maybe? Spoiler alert: The title text references a particular part of The Martian' s story: The astronaut stranded on Mars has previously established communications with Earth by repurposing the Pathfinder space probe that NASA landed on Mars in 1997. While working on another piece of equipment, he accidentally subjects the probe to an electrical short-circuit, destroying its electronics and "bricking" it. " Bricking " is a term in consumer electronics which essentially means to cause an electronic device to become non-functional and essentially no more useful than a "brick". The term is commonly used in respect of an unrecoverable failure of software and often a corruption of firmware . An unexpected "bricking" can be very surprising, and in a case where the item is critical, could be devastating. This bricking scene from the book was left out of the movie. [Cueball is sitting at a desk using a computer and White Hat walks in.] Cueball: Ooh, trailer for The Martian! White Hat: What's that? Cueball: Movie of a book I liked. White Hat: Should I read it? [Cueball pivots on chair and turns away from computer to face White Hat.] Cueball: Depends. You know the scene in Apollo 13 where the guy says "we have to figure out how to connect this thing to this thing using this table full of parts or the astronauts will all die? White Hat: Yeah? [Cueball pivots on chair again and resumes using computer while talking. White Hat looks at his smart phone.] Cueball: The Martian is for people who wish the whole movie had just been more of that scene. White Hat: How on earth did that become a big-budget thing with Matt Damon? Cueball: No idea, but I'm so excited. In a video interview by Adam Savage with Andy Weir the author of The Martian says that his goal was to make the whole book like the mentioned scene from Apollo 13 - exactly what the comic is saying. The video was posted on YouTube the day after the xkcd comic. In the end, The Martian likely didn't disappoint the big-budget movie makers, grossing more than $630 million against a budget of $108 million.

Types

Types

https://www.xkcd.com/1537

https://www.explainxkcd.com/wiki/index.php/1537:_Types

[Caption above the black part of the comic:] My new language is great, but it has a few quirks regarding type: [The rest of the comic is written in a black rectangle. All text to the left of ">" is written in gray. Text to the right of the ">" on the lines with numbers are in white, and then gray text on the other lines. There seems to be a missing ">" after line no. 3.] [1]> 2+"2" => "4" [2]> "2"+[] => "[2]" [3] (2/0) = > NaN [4]> (2/0)+2 = > NaP [5]> "" + "" = > ' "+" ' [6]> [1,2,3]+2 = > False [7]> [1,2,3]+4 = > True [8]> 2/(2-(3/2+1/2)) = > NaN.000000000000013 [9]> Range("   ") = > (' " ',"! "," ","!",' " ') [10]> + 2 = > 12 [11]> 2+2 = > Done [14]> Range(1,5) = > (1,4,3,4,5) [13]> Floor(10.5) = > | = > | = > | = > |_ _ _10.5_ _ _

This comic is a series of programming jokes about a ridiculous new programming language, perhaps inspired by Mathematica and Wolfram Language — the latter was used by Randall many times before. Maybe it's also inspired by Gary Bernhardt's CodeMash 2012 lightning talk on JavaScript's unpredictable typing. In the talk, the highly technical audience was unable to correctly guess the results of adding various JavaScript types and roared with laughter when they were revealed. The programming language shown in this comic has types even more unpredictable than JavaScript. Most regular programming languages distinguish types, e.g. integers, strings, lists… all of which have different behaviours. But for instance, the operation "+" is usually conventionally defined over more than one of these types. Applied to two integers, it returns their sum. Applied to two strings (denoted by being enclosed in quotes) it concatenates them: While these behaviours are standard, conventional, and intuitive, there is a huge amount of variation among programming languages when you apply an operation like "+" to different types. One logical approach is to always return an error in all cases of type mixing, but it is often practical to allow some case mixing, since it can hugely simplify expressions. Variation and lack of a clearly more intuitive behaviour leads some languages to have weird results when you mix types. Weird results abound in the new XKCD programming language: The title text contains three further examples relating to color. color.rgb("blue") returns the hexadecimal code for pure blue (as would be used in HTML, for example), which is how a real programming language might work. The lookup for "yellowish blue" returns "NaN" (Not a Number) again, which makes sense at one level because there is no such color as "yellowish blue" (yellow and blue are opposites on the RGB color triangle , making yellowish-blue an impossible colour , which can only be perceived with great difficulty through contrived figures). However a more typical result would have been a failure indicating that the color database does not include the name, in the same way that a typo such as "bluw" would. (Note that HTML does explicitly attempt to handle all "color names". For the record, "yellowish blue" is a dark blue with an imperceptible amount of red — #0E00B0 .) Similarly sorting the colors would normally produce some defined ordering, such as alphabetical, but in this language it generates the string "rainbow". It seems that Randall's new language understands color theory in an unusually deep way. [Caption above the black part of the comic:] My new language is great, but it has a few quirks regarding type: [The rest of the comic is written in a black rectangle. All text to the left of ">" is written in gray. Text to the right of the ">" on the lines with numbers are in white, and then gray text on the other lines. There seems to be a missing ">" after line no. 3.] [1]> 2+"2" => "4" [2]> "2"+[] => "[2]" [3] (2/0) = > NaN [4]> (2/0)+2 = > NaP [5]> "" + "" = > ' "+" ' [6]> [1,2,3]+2 = > False [7]> [1,2,3]+4 = > True [8]> 2/(2-(3/2+1/2)) = > NaN.000000000000013 [9]> Range("   ") = > (' " ',"! "," ","!",' " ') [10]> + 2 = > 12 [11]> 2+2 = > Done [14]> Range(1,5) = > (1,4,3,4,5) [13]> Floor(10.5) = > | = > | = > | = > |_ _ _10.5_ _ _

Lyrics

Lyrics

https://www.xkcd.com/1538

https://www.explainxkcd.com/wiki/index.php/1538:_Lyrics

[Cueball sits in a chair holding something. A speaker on a counter behind him is transmitting music. Four lines of wavy undecipherable lyrics emanate from the speaker. The lyrics are surrounded by musical notes. Below is the best attempt to write this down in text, also using capitals when they are clearly there in the comic.] I CANT₣∇EN +ELҼ ⊤HER A|N⊃Г⊕N6 ƒHE W(AN NAp. HADβE Aūτ|ƒA!NNNG∩fҠILL... FOR♡ITiNn⊣GLOOOO!VEEE ?.- [Caption below the frame:] Sometimes I wonder what it would be like to be able to understand song lyrics without looking them up. Get up in the morning Get up in the morning slaving for bread, sir sleeping for for bread, sir So that every mouth Sold out to every monk can be fed and beef-head Poor oh-oh me Israelites me ears are alight My wife an' my kids Why find my kids? them a pack up an' a leave me They buck up and a-leave me Darlin' she said, Darling Cheese head I was yours to be seen I was yards too greasy Poor oh-oh me Israelites me ears are alight I think that's what he says But I need to hear it on a Maxell (There is a picture of a cassette tape below that last line of text.)

For some modern songs, the vocalist chooses to perform the track in a way that emphasizes emotion, accent or style over clear pronunciation of the lyrics. Some forms of music, for example the Jazz style Scat, use purely nonsensical lyrics while some styles of dance music use a single line of lyrics repeated throughout the track. There are also certain types of people that may describe themselves as "lyric deaf", which is sort of the lyrical equivalent to being tone deaf , although it doesn't have an underlying medical understanding. Some people that describe themselves as tone deaf are even quite musically capable. The comic is illustrating (in text form) how listening to such a song feels before you have learned what the actual lyrics are. The lyrics are represented in an indecipherable way, with a few mildly recognizable words. This represents the auditory experience of being able to hear and understand some words (perhaps incorrectly), but not all of them. Another example of this experience can be seen in this British TV commercial from the 1980s, showing someone who has misheard Desmond Dekker song Israelites so for instance the line Poor me Israelites becomes Oh-oh my ears are alight . See more details in the trivia section. This experience is similar to that shown by the character Havelock Vetinari the Patrician of Ankh-Morpork , in Terry Pratchett 's Discworld book Soul Music (see part of book here ). Rather than listening to music, he preferred to read the printed sheet music: In fact the kind of music he really liked was the kind that never got played. It ruined music, in his opinion, to torment it by involving it on dried skins, bits of dead cat and lumps of metal hammered into wires and tubes. It ought to stay written down, on the page, in rows of little dots and crotchets, all neatly caught between lines. Only there was it pure. It was when people started doing things with it that the rot set in. Much better to sit quietly in a room and read the sheets, with nothing between yourself and the mind of the composer but a scribble of ink. Having it played by sweaty fat men and people with hair in their ears and spit dribbling out of the end of their oboe... well, the idea made him shudder. For a related experience see Mondegreen . The title text elaborates on the fact that Randall has the same experience when trying to understand song lyrics as when he sees text in his dreams. The last part of the title text is written in strange scripts to illustrate how he feels when seeing text in his dreams. Translated it says: it's hard to read and I can't focus. Note that it looks like the song lyrics were written by drawing in a tool, like MS Paint, and then cutting out pieces and shifting them slightly. The closest guess on the lyrics is this: I can't even tell her Anything she wanna Had outstanding skill Beautiful Forgetting love. (Note that the first line also might be I can't even help her .) It is very likely that Randall completely made up these lyrics himself and if any song coincidentally share some part of them it only happens because Randall has chosen some very cliché lyrics, that would thus be likely to occur in some pop songs. Nevertheless, here below are some possible song references, in which the exact line from above occurs: Joe Budden 's song More of Me From the lyrics : World keeps spinning, learned sinners keep sinning And I can't even tell her some fights ain't fight worthy Cause my pops got 20 years clean, but her pops got 20 years dirty Bill Anderson's song Baby's Blue Again From the lyrics : Oh Lord, and I can't even help her All I can do is just wait Until the clouds are all blown away Johnny Cinco's song She Wanna From the lyrics : Buy here anything she wanna Fly in anything she wanna Try on anything she wanna Chino Brown's song Love Again From the lyrics : I was at a point in my life Of just forgetting love Until the day you touched me [Cueball sits in a chair holding something. A speaker on a counter behind him is transmitting music. Four lines of wavy undecipherable lyrics emanate from the speaker. The lyrics are surrounded by musical notes. Below is the best attempt to write this down in text, also using capitals when they are clearly there in the comic.] I CANT₣∇EN +ELҼ ⊤HER A|N⊃Г⊕N6 ƒHE W(AN NAp. HADβE Aūτ|ƒA!NNNG∩fҠILL... FOR♡ITiNn⊣GLOOOO!VEEE ?.- [Caption below the frame:] Sometimes I wonder what it would be like to be able to understand song lyrics without looking them up. Get up in the morning Get up in the morning slaving for bread, sir sleeping for for bread, sir So that every mouth Sold out to every monk can be fed and beef-head Poor oh-oh me Israelites me ears are alight My wife an' my kids Why find my kids? them a pack up an' a leave me They buck up and a-leave me Darlin' she said, Darling Cheese head I was yours to be seen I was yards too greasy Poor oh-oh me Israelites me ears are alight I think that's what he says But I need to hear it on a Maxell (There is a picture of a cassette tape below that last line of text.)

Planning

Planning

https://www.xkcd.com/1539

https://www.explainxkcd.com/wiki/index.php/1539:_Planning

[Megan and Ponytail are walking] Ponytail: Why are people so comfortable handing Google and Facebook all this control over our lives? Megan: I dunno. Megan: Our species built thousands of nuclear weapons, scattered them around the planet, and then moved on to other things. Megan: Maybe it's best to accept that some of this big-picture planning is just happening on autopilot.

Big companies have always tried to get the greatest amount of information from their customers, because that translates into more money earned. However, ability to gather, store and process such information is limited by the technology available. With the recent development of computers, this ability has grown far more than anyone could have suspected just 20 years ago; to the point that companies like Google or Facebook get almost unimaginable amounts of data from their users; and this data is gathered and stored automatically and can be efficiently accessed. This data is routinely used to, for example, tailor online ads to the browsing history of the user seeing the ad. They could potentially be used for more evil purposes, like selling the medical history of users to insurance companies. Many users don't feel that they're giving out so much information, and in fact that few of them have given Google or Facebook their medical history. However some leaks have proven quite the opposite. In the AOL leak referenced in 155: Search History , searches for "how does a male's cocaine use affect a fetus", "hysterectomy" or "8 alcohol drinks a day", surely would be interesting for a medical insurance company to know. In the comic, Ponytail is puzzled because people are not worried about Google or Facebook using their information in evil ways; however Megan raises a quite fair point, namely that the huge amount of nuclear weapons in existence is much scarier, and that was worrying to the general public in the 1980s, however people have grown tired of that and now concerns have moved to internet privacy only because it's "new". What is perceived as dangerous or worrying follows trends and fashions not directly related to real danger (i.e. "happen on auto-pilot"). The point Megan is making is that maybe it's better to just accept that things work in this way and go with the flow. This is very similar to what happens in 1480: Super Bowl or 1534: Beer . The title text hypothesizes a similar conversation being held ten years later (presumably in 2025, ten years after the comic was published), in which the two aspects of the above have been inexplicably mixed. A future equivalent to Ponytail asks why we all think it is OK to hand over the control of our nuclear weapons to Google and Facebook, which would certainly be a nonsensical (and deeply troubling) route to take. This could also be seen as another step toward the singularity , from which perspective handing over control of nuclear weapons could be desirable, catastrophic, implicit and/or unavoidable. This comic was posted on the day after Vladimir Putin had announced that Russia would add 40 new intercontinental ballistic missiles to its nuclear stockpile within the year. Within a year Randall has made several other comics about nuclear weapons, the first of these, 1520: Degree-Off , came just 1½ month before this one. Later these two comics were released early in 2016: 1626: Judgment Day and 1655: Doomsday Clock . Nuclear weapons are also mentioned twice in Thing Explainer , specifically they are explained in the explanation for Machine for burning cities about thermonuclear bombs , but they are also mentioned in Boat that goes under the sea about a submarine that carries nukes. All three comics and both explanations in the book, does like this comic, comment on how crazy it is that we have created enough firepower to obliterate Earth several times (or at least scourge it for any human life) [ citation needed ] . [Megan and Ponytail are walking] Ponytail: Why are people so comfortable handing Google and Facebook all this control over our lives? Megan: I dunno. Megan: Our species built thousands of nuclear weapons, scattered them around the planet, and then moved on to other things. Megan: Maybe it's best to accept that some of this big-picture planning is just happening on autopilot.

Hemingway

Hemingway

https://www.xkcd.com/1540

https://www.explainxkcd.com/wiki/index.php/1540:_Hemingway

Hemingway's Rough Drafts [A list of rough draft stories.] For sale: This Gullible Baby's Shoes Baby Shoes For Sale By Owner Actually, there's no evidence Hemingway wrote Free Shoes, Provided You Overpower Baby For Sale: Weird Baby's Toe Shoes For Sale: Baby Shoes ✓ Prime eligible Though popularly attributed to Hemingway, the This Weird Trick Covers Baby Feet! For Sale: Baby Shoes, Just Hatched Sale: Seven-League Boots (Expedited Shipping) Complete this survey for free shoes! Shoes , by Ernest Hemingway [ citation needed ] This is my greatest short story. For sale: Baby shoes (-1) [cursed] <blink><marquee> Baby Shoes! </marquee></blink> For Sale: Baby-sized Saddle, Bobcat Hemingway Busted for Craigslist Shoe Scam

This comic is a reference to the six-word short story For sale: baby shoes, never worn , which has been commonly attributed to famous author Ernest Hemingway (the disputed authorship of the story is referenced several times in the comic). The comic plays on the fact that the original story takes the form of a short advertisement that might have been seen in a newspaper, and makes up alternate versions that use various modern 'standards' that did not exist in Hemingway's time. In keeping with the original, each example remains six words long. The title text obeys this rule, too. Many of the drafts poke fun at the tragedy that the original story suggests. With the original ("For Sale: Baby shoes, never worn"), readers could infer that the baby who would have worn the shoes must have died. Randall tries to make the reader infer other, more absurd things instead. The comic also alludes to Hemingway's practice of repeatedly re-working drafts of his novels before publication. For example, he is reported to have rewritten the final passage of A Farewell To Arms 39 times. Later editions of his works include these rough drafts, allowing the devoted reader to understand how the work developed. The following are the various drafts offered in the comic. The title text continues the reference to 325: A-Minus-Minus , but inverts the situation. Rather than unexpectedly receiving a bobcat by package, this time the package contains a regular item instead of the expected bobcat. In keeping with the theme of the comic, the review is written in only six words. Hemingway's Rough Drafts [A list of rough draft stories.] For sale: This Gullible Baby's Shoes Baby Shoes For Sale By Owner Actually, there's no evidence Hemingway wrote Free Shoes, Provided You Overpower Baby For Sale: Weird Baby's Toe Shoes For Sale: Baby Shoes ✓ Prime eligible Though popularly attributed to Hemingway, the This Weird Trick Covers Baby Feet! For Sale: Baby Shoes, Just Hatched Sale: Seven-League Boots (Expedited Shipping) Complete this survey for free shoes! Shoes , by Ernest Hemingway [ citation needed ] This is my greatest short story. For sale: Baby shoes (-1) [cursed] <blink><marquee> Baby Shoes! </marquee></blink> For Sale: Baby-sized Saddle, Bobcat Hemingway Busted for Craigslist Shoe Scam

Voice

Voice

https://www.xkcd.com/1541

https://www.explainxkcd.com/wiki/index.php/1541:_Voice

[Megan and Ponytail are walking.] Megan: Are you doing anything later? Ponytail: I was th- I can only control my voice once every six years. Please, you have to -inking of going out, but no real plans. Megan: ...What was that? Ponytail: Haha, what?

During a casual talk with Megan , Ponytail suddenly interrupts her normal speech stating that she is for some reason only capable of controlling her own voice once every six years. Apparently only for a very brief time since she immediately returns to the casual talk, continuing her previous sentence mid-word before being able to tell Megan how she could help her. Upon Megan's confused request, she denies knowledge of the occurrence, although in a somewhat suspicious way, using possibly fake laughter. It could be this was just a prank by Ponytail, to tease Megan, but given her fake laughter reply to Megan's inquiry and the continuing comment in the title text it seems most likely that Ponytail is indeed possessed by some sort of entity that prevents her from expressing her own thoughts, except for a very short time every six years. Of course this may just be her way of continuing with the prank; see a previous case of such a prank below . In case it is not a prank it would thus appear that Ponytail's usual "self" is indeed this possessing entity. Whether this entity is actually aware that the "real" Ponytail did speak, or if it actually does not know that it was interrupted (since it continued mid-word) is not clear from the last response to Megan. The title text suggests that Ponytail is possessed by some sort of inhuman entity , most likely an alien or AI , unfamiliar with movies and eating. See below for related comics . The comic, 1530: Keyboard Mash , also revolves around the same theme of a non-human entity trying to convince other humans that it is in fact a human. This is most clearly referenced in the title text of this comic. In Keyboard Mash, it is a spider that tries to chat like it was a human, making statements that are true if you are human, but which humans would never utter in a conversation like here - put some food in our normal mouths! However, the pretended 'human' being (the spider) is not seen by the other person in this comic. As opposed to this one where Megan speaks directly with Ponytail. It has already been established recently, in 1528: Vodka , that Ponytail's voice can be hijacked by non-human entities. That time it was the vodka she was drinking that took over. It is possible that this is continuing or caused by the same openness to possession as shown here. It is also possible that she simply thinks possession jokes are funny and once again jokes with Megan. Six years ago today, which according to this comic was the last time Ponytail had control of her own voice, this comic 600: Android Boyfriend was posted. Ponytail acquired an android boyfriend. It seems unlikely that this older comic has any relation with this particular episode - except that this comic mentions a six-year period and Ponytail is also in that comic. Ponytail is mainly a filler character, showing up when two females are needed or when a large group of people are present. It is important to note that Ponytail , like most xkcd stick figures , usually does not represent the same character in each comic. This Ponytail is likely unrelated to other instances of Ponytail. [Megan and Ponytail are walking.] Megan: Are you doing anything later? Ponytail: I was th- I can only control my voice once every six years. Please, you have to -inking of going out, but no real plans. Megan: ...What was that? Ponytail: Haha, what?

Scheduling Conflict

Scheduling Conflict

https://www.xkcd.com/1542

https://www.explainxkcd.com/wiki/index.php/1542:_Scheduling_Conflict

[Picture showing a newspaper with a big headline over a picture. In the picture there is a banner over an empty lectern with a microphone. Only the headline and the text on the banner in the picture is readable. All other text in the newspaper is just lines.] National Scheduling Conflict Championships canceled Banner text: NSCC 2015

There are two humorous features in this comic: a pun formed by syntactic ambiguity ; and the farce of a major national event that is by nature self-defeating. The comic shows a newspaper with a large headline: National Scheduling Conflict Championships canceled Many readers naturally see a phrase break between the two lines, so that it means "there has been a scheduling conflict on a national scale, which has caused championships to be cancelled" (what the conflicts are, and which championships have been cancelled, is not made clear). However, the correct interpretation is implied by the picture of an empty lectern under a banner with the text NSCC 2015. The headline should be read like this: National Scheduling Conflict Championships (NSCC) canceled This comic thus envisions a "National Scheduling Conflict Championship" (NSCC), presumably as the culmination of some larger scheduling-conflict competition. It is unclear if the goal of the event is to have a scheduling conflict and miss it, or if there are actual challenges at the event, but this year's event has been canceled, most likely due to scheduling conflicts. Whether it is the contestants that miss the event, as it's their nature to always have a scheduling conflict, or if it is the organizers that have an issue is untold. The question is whether the event's cancellation is a success in itself or just a predictable failure of such an event. The comic could also refer to the very common political ploy of using a "scheduling conflict" as an excuse to miss an event where the politician expects to be challenged or questioned on an issue he wishes to avoid. This is so frequent that it has become a cliché in American politics. The abbreviation NSCC is related to many other national sports organizations like NFL and NBA . (The most common use of it online seems to be for Nova Scotia Community College ). The title text mentions that is was impossible to reach either a spokesperson for the organization (NSCC) or last year's world-champ (winner of the WSCC) for a comment. Thus continuing the problem with schedules for people involved in this type of championship. The world-champion could be assumed to be able to comment in this national championship (probably the American championship given that Randall is American), since the paper is looking for a comment on the national championship. But this proves that at least a world champion was crowned last year, so this type of competition is not always canceled. It is not a necessity for a spokesperson for a sports organization to be good at the sport in question. However it will often be former competitors within the sport or at least people with interest in this kind of activity that takes an interest in such an organization, thus making it likely that they would also be good (or like to think they are good) at achieving scheduling conflicts. A similar type of competition was mentioned earlier in 1466: Phone Checking in which it was difficult to load the web page with the result of the competition because it was overloaded by all those compulsive phone-checkers that have an interest in such a contest. They continually try to reload the home page of the CPCC (i.e. compulsive phone-checking championship) making the web page go down. [Picture showing a newspaper with a big headline over a picture. In the picture there is a banner over an empty lectern with a microphone. Only the headline and the text on the banner in the picture is readable. All other text in the newspaper is just lines.] National Scheduling Conflict Championships canceled Banner text: NSCC 2015

Team Effort

Team Effort

https://www.xkcd.com/1543

https://www.explainxkcd.com/wiki/index.php/1543:_Team_Effort

[Megan is on a stage receiving an award from Ponytail, the latter of whom is standing behind a lectern.] Megan: I'd like to thank my director, my friends and family, and–of course–the writhing mass of gut bacteria inside me. Megan: I mean, there's like one or two pints of them in here; their cells outnumber mine! Megan: Anyway, this was a real team effort.

Megan has won an award at a ceremony (presumably movie-related and possibly an Academy Award , as she mentions her director). When a person receives a major award, they give an acceptance speech which traditionally begins with the recipient thanking people who have helped them achieve the honour. Sometimes when a number of people are mentioned, the recipient will say that it was a team effort - a comment which elevates the "helpers" to virtually the same level as the recipient. Megan's acceptance speech takes things a step further; she thanks not only her director, family, and friends, but also the bacteria that populate her gastrointestinal tract. She states that the bacterial cells outnumber hers, likely referencing the misconception at the time that bacterial cells outnumber human cells by a factor of 10 to 1. More recent estimates have gotten values around 1:1. While the bacteria in the gut make digestion possible, the ecosystem formed by bacteria in the urogenital tract and on the skin also protect human health. In short, without them Megan would die — and not be able to win the award. To thank her bacteria is comparable to thanking her parents: they did not really contribute to the movie, but without them there would not have been a Megan, and no award. Recently, it has been shown that the gut bacteria has an effect on emotions, thoughts and mood. link In the title text, Megan contemplates how to thank her microorganisms and considers to eat the trophy after having it cut in pieces. This is an extremely bad idea, because it might kill both her and the microorganisms. A pint is a volume of about half a liter (specifically, the U.S. fluid version is 28 and 7/8 cu.in.). [Megan is on a stage receiving an award from Ponytail, the latter of whom is standing behind a lectern.] Megan: I'd like to thank my director, my friends and family, and–of course–the writhing mass of gut bacteria inside me. Megan: I mean, there's like one or two pints of them in here; their cells outnumber mine! Megan: Anyway, this was a real team effort.

Margaret

Margaret

https://www.xkcd.com/1544

https://www.explainxkcd.com/wiki/index.php/1544:_Margaret

[Margaret, shown in full body, is alone. She is talking while looking out towards the reader.] Margaret: Are you there, God? It's me, Margaret. Margaret: I know you're listening. [Zoom in on her face and torso.] Margaret: Are you scared, God? Margaret: Are you? [Zooming so far in that not even her whole face is visible.] Margaret: You should be. [Zooming far out showing her in a white silhouette against a black sky, standing on the white earth.] Margaret: Margaret is coming for you .

This comic uses the starting lines of an innocent children's book and creates irony by delivering a dark message. In the book Are You There God? It's Me, Margaret. by Judy Blume , the opening lines are "Are you still there, God? It's me, Margaret. I know you're there, God. I know you wouldn't have missed this for anything! Thank you, God. Thanks an awful lot..." These lines describe a prayer, in which Margaret privately speaks to God, expressing gratitude and seeking guidance. In the second and third panels, Margaret asks God "Are you scared, God?", and states "You should be". This is similar to threats delivered in some action movies, such as Taken, in which the protagonist or antagonist speaks directly to their opponent, issuing threats and indicating that they are coming after their opponent. The final panel is a shot of Margaret standing imposingly in a dark landscape, and a caption over the top of the image says "Margaret is coming for you", making this comic reminiscent of an action movie trailer. The irony is that "Are You There, God? It's Me, Margaret." is a very innocent book, especially when compared to this type of action movie. The title text is a mashup of three of Blume's other books: Otherwise Known as Sheila the Great , The Pain and the Great One , and Then Again, Maybe I Won't , and likely the inspiration for the dark lines in the comic. [Margaret, shown in full body, is alone. She is talking while looking out towards the reader.] Margaret: Are you there, God? It's me, Margaret. Margaret: I know you're listening. [Zoom in on her face and torso.] Margaret: Are you scared, God? Margaret: Are you? [Zooming so far in that not even her whole face is visible.] Margaret: You should be. [Zooming far out showing her in a white silhouette against a black sky, standing on the white earth.] Margaret: Margaret is coming for you .

Strengths and Weaknesses

Strengths and Weaknesses

https://www.xkcd.com/1545

https://www.explainxkcd.com/wiki/index.php/1545:_Strengths_and_Weaknesses

[Ponytail is shown sitting on a swivel chair, to the left of a desk.] Ponytail: What would you say is your biggest weakness? [The view expands to show Cueball sitting on another swivel chair, on the opposite side of the desk.] Cueball: Probably that I'm a giant tangle of parts that don't always work right, so I can die easily. Ponytail: Biggest strength? Cueball: There will come a day when I'm either an ancestor to all living humans, or to none of them. Ponytail: Where do you see yourself in five years? Cueball: Probably not the ancestor of all living humans yet. But you never know!

Cueball is in a job interview and is being asked stereotypical job interview questions by Ponytail , "What is your greatest weakness?", "What is your greatest strength?" and "Where do you see yourself in five years?" In a roundabout way, Cueball answers that he is a living organism, and as such he has inherent flaws which could cause him to die. This is a reference to the fact that biological systems are "messy" and are not always optimal in design or operation. For example, cancer is a disease where the cellular machinery that governs cell replications breaks down and prolific cell division happens, endangering the organism through the creation of tumors. While this is a true weakness, it is also a weakness of all biological organisms and is not likely to help the interviewer determine if he is qualified for the job. However, it is likely to help the interviewer determine if he is right for the job — because the interviewer is likely to presume that a person who gives silly and unhelpful answers is not right for most positions. For the second question Cueball answers that he will one day be the ancestor to all living humans or none of them. As you go farther and farther into the future the ratio of people alive will either go to 0% or 100% of the descendants of the character. The most recent common ancestor (MRCA) for humans is unknown but occurred some time after Mitochondrial Eve , around 140,000 years ago. If the MRCA's ancestors are traced back, the Identical ancestors point can be found, at which point the entire population are either ancestors of all living humans or of no living humans. In the last frame, for Cueball to be the ancestor to all living humans within 5 years means that all the humans who are not his children or grandchildren (including Cueball himself), must have died in a near total extinction of the human race - his apparent optimism about the possibility of this occurring would therefore be worrisome. The overarching joke is that, rather than answer Ponytail's questions with answers relevant to the job she's interviewing him for, Cueball is answering her questions from an existential standpoint. He may be assuming that she wishes to assess his fitness as an organism from a genetic perspective (in which his biggest limitation is survival time and mortality), or he may simply be misinterpreting or deliberately avoiding her questions from a professional perspective. The title text takes this further, equating producing offspring during an interview (which would be awkward for all involved) with something that may actually help assess a candidate's efficacy as an employee, namely writing out a sorting algorithm on the spot, another stereotypical interview question (see also 1185: Ineffective Sorts , especially the bottom left panel). In 1088: Five Years , Beret Guy is also asked where he will be in five years, and he later interviews Hairy in 1293: Job Interview . Other job interviews were portrayed in 125: Marketing Interview and 1094: Interview . [Ponytail is shown sitting on a swivel chair, to the left of a desk.] Ponytail: What would you say is your biggest weakness? [The view expands to show Cueball sitting on another swivel chair, on the opposite side of the desk.] Cueball: Probably that I'm a giant tangle of parts that don't always work right, so I can die easily. Ponytail: Biggest strength? Cueball: There will come a day when I'm either an ancestor to all living humans, or to none of them. Ponytail: Where do you see yourself in five years? Cueball: Probably not the ancestor of all living humans yet. But you never know!

Tamagotchi Hive

Tamagotchi Hive

https://www.xkcd.com/1546

https://www.explainxkcd.com/wiki/index.php/1546:_Tamagotchi_Hive

My Hobby [A tree graph of Tamagotchis.] Running a massive distributed computing project that simulates trillions and trillions of Tamagotchis and keeps them all constantly fed and happy

A part of the " My Hobby " series, this describes a distributed computing network using an automated system to simultaneously run trillions of Tamagotchis. As with most of the "My Hobby" series, the concept would work, and is closely connected to real world activities, but twisted enough to make it inherently absurd. A Tamagotchi is a keychain-sized virtual pet simulation game from 1996. Ostensibly for children, they had appeal for people of all ages. The characters are colorful and simplistically designed creatures based on animals, objects, or people. Beginning with the 2004 Tamagotchi Plus/Connection, a second wave of Tamagotchi toys emerged, featuring a different graphic design by JINCO and gameplay which elaborated upon the first generations. However, the story behind the games remained the same: Tamagotchis are a small alien species that deposited an egg on Earth to see what life was like, and it is up to the player to raise the egg into an adult creature. The creature goes through several stages of growth, and will develop differently depending on the care the player provides, with better care resulting in an adult creature that is smarter, happier, and requires less attention. Gameplay can vary widely between models, and some models, such as TamagoChu, require little to no care from the player. Tamagotchi has a shrinking fan base. Distributed computing is a field of computer science that studies distributed systems. A distributed system is a software system in which components located on networked computers communicate and coordinate their actions by passing messages. The components interact with each other in order to achieve a common goal. Examples of distributed systems vary from service-oriented architecture based systems to multiplayer online games to peer-to-peer applications. Distributed computing is often used for tasks that require resources which would otherwise be impossible or prohibitively expensive to manage with single computers. This may include large Bitcoin network mining operations, the Worldwide LHC Computing Grid or, yes, running trillions of simultaneous Tamagotchis using an AI protocol. That said, using AI to keep trillions of Tamagotchis perfectly taken care of is a complete waste of time; the whole point of Tamagotchi is the challenge of caring for the digital pet yourself. "The Singularity" in the title text refers to the technological singularity ; a concept prevalent in science fiction and discussions of artificial intelligence (AI). The idea is that AI would become so sophisticated compared to a human brain that no human would be able to predict its behaviour, motivations etc. from that point onward, and potentially human history after that point would therefore become unpredictable, as AIs would play dominant roles in determining its direction. It uses the metaphor of a mathematical "singularity", which is a point where established rules can no longer apply (for example, in a black hole or during the Big Bang, physical conditions are such that the physical laws we use can no longer meaningfully predict what happens). An AI that is more sophisicated than a human brain could presumably then simulate human brains within itself, making it possible to upload human consciousness into a machine-simulated environment (see simulated reality and the simulation hypothesis ). Thus, much science fiction that is based on the idea of The Singularity also focuses on the creation of a virtual world that much of the human race decides to plug itself into, much like the Tamagotchi Hive that Randall has created. Randall's mind, and the processing power in his computer, is far greater than any individual Tamagotchi mind, so simulating Tamagotchis becomes trivial for Randall, and no Tamagotchi could predict or control its own history with Randall around, in a humorous analogy with the Singularity concept. My Hobby [A tree graph of Tamagotchis.] Running a massive distributed computing project that simulates trillions and trillions of Tamagotchis and keeps them all constantly fed and happy

Solar System Questions

Solar System Questions

https://www.xkcd.com/1547

https://www.explainxkcd.com/wiki/index.php/1547:_Solar_System_Questions

Questions I have about the solar system (some answered) Why is the the Moon so blotchy? Lava Why are all the blotches on the near side? Did Mars have seas? Yes (briefly?) Was there life on Mars? What's Titan like? Cold, yellow, lakes + rivers (methane) What was Earth like during the Hadean? Is the Oort Cloud a real thing? Why is the Sun's corona so hot? Something about magnets? What are comets like? Precipitous Where's Philae, exactly? What's Pluto like? [Soon!] What's Charon like? Why don't we have in-between-sized planets? What's Ceres like? [Working on it!] Why is Europa so weird-looking and pretty? Ice over a water ocean Why is Io so weird-looking? Sulfur volcanoes (? in the wrong places?) Why are so many Kuiper Belt objects red? What are those spots on Ceres? What's in the seas under Europa's ice? Which of the other moons have seas? Several What are the big white things in Titan's Lakes? What do Jupiter's clouds look like up close? What's all that red stuff in the Great Red Spot? What's pushing the Pioneer Probes? Heat from the RTG What pushes spacecraft slightly during flybys? Where are all the Sun's Neutrinos? Oscillating Why is there so much air on Titan? Why does the Kuiper Belt Stop? Why is Iapetus weird-colored? Why does Iapetus have a belt? What's the deal with Miranda? Did Uranus and Neptune change places? Did the Late Heavy Bombardment happen? Did life start before it? Is Europa covered in ice spikes? Why haven't we built a big inflatable extreme sports complex on the moon?

This comic is a list of questions which Randall has about the Solar System, which at first glance may appear to be things that Randall would like to learn about. In actuality, most of the questions have not been satisfactorily answered or proven by anyone in the scientific community . The title text refers to the 2015 FIFA Women's World Cup which was won by the USA the day before. The nylon wings and flying may be a reference to two passages from 3001: The Final Odyssey, one where Frank Poole tries out various wings while in an extremely low gravity environment, and one where he remarks while watching Swan Lake that Tchaikovsky could never have imagined a performance where the dancers were actually flying (due to aforementioned low gravity). This is also a reference to the last point on the list, because if we had such a stadium on the moon, maybe it would be possible to use such wings to make very long floating leaps. Questions I have about the solar system (some answered) Why is the the Moon so blotchy? Lava Why are all the blotches on the near side? Did Mars have seas? Yes (briefly?) Was there life on Mars? What's Titan like? Cold, yellow, lakes + rivers (methane) What was Earth like during the Hadean? Is the Oort Cloud a real thing? Why is the Sun's corona so hot? Something about magnets? What are comets like? Precipitous Where's Philae, exactly? What's Pluto like? [Soon!] What's Charon like? Why don't we have in-between-sized planets? What's Ceres like? [Working on it!] Why is Europa so weird-looking and pretty? Ice over a water ocean Why is Io so weird-looking? Sulfur volcanoes (? in the wrong places?) Why are so many Kuiper Belt objects red? What are those spots on Ceres? What's in the seas under Europa's ice? Which of the other moons have seas? Several What are the big white things in Titan's Lakes? What do Jupiter's clouds look like up close? What's all that red stuff in the Great Red Spot? What's pushing the Pioneer Probes? Heat from the RTG What pushes spacecraft slightly during flybys? Where are all the Sun's Neutrinos? Oscillating Why is there so much air on Titan? Why does the Kuiper Belt Stop? Why is Iapetus weird-colored? Why does Iapetus have a belt? What's the deal with Miranda? Did Uranus and Neptune change places? Did the Late Heavy Bombardment happen? Did life start before it? Is Europa covered in ice spikes? Why haven't we built a big inflatable extreme sports complex on the moon?

90s Kid

90s Kid

https://www.xkcd.com/1548

https://www.explainxkcd.com/wiki/index.php/1548:_90s_Kid

[Two kids, with very different hair style, are in a playground. A fence is visible in the background, and on the ground appear to be various items including a puddle or rug and toy blocks.] Scruffy-haired kid: Ugh don't you hate how parents are all "Eat your carrots" and "LOL, remember Rugrats and Doug? Share if you're a 90's kid!" [Caption below the panel:] The median age at first birth in the US is 25, which means the typical new mother is now a 90's kid.

This is another example where Randall describes the inexorable passage of time. The children are complaining about things their parents tell them, as children often do. Their first complaint is something recognizable, the usual "just eat your vegetables, they're good for you." The second is about a comment "LOL, remember Rugrats and Doug? Share if you're a 90's kid" which, however, is a generic social media comment that a "90's kid" would make, not something you would expect a mother to say. At least not in the context of things their children are embarrassed about. But it illustrates that the teens and tweens of yesteryear are now adults, and parents at that. According to the CIA World Factbook, in the USA the median age of mothers at their first birth is 25.6 (2011 estimate). On the date this comic was published, this would center the mother's own birth date in very late 1989. Although there are various interpretations of the term "90's kid," most center around the person in question having had most or all of their childhood during the 1990s. The stereotypical '90s kid has a strong attachment to objects, movies, TV shows, phrases etc. from the era of their childhood, which bring back memories of their younger days. In this comic Randall picks up on a number of things which could be used to identify a '90s kid: Given that the children shown in the comic appear to be somewhat older than newborn babies is not contradictory, since a 90s kid is anyone who was a kid during the '90s. So that would also include kids who turned five in 1990 or even ten; so in 2015 (publishing of this comic) a 90s kid could easily be more than 30 years old and thus have children more than 10 years old. The title text suggests that viewing a child of one's own peering through such a barrier elicits nostalgia for the Rugrats cartoon. A baby gate is a semi-fixed piece of child-safety equipment to restrict a small child, typically a toddler, from leaving a safe area of a house, and especially to prevent access to stairways (up or down, where falls may happen), without overly inconveniencing an adult who can open the gate. Baby gates, fully enclosed playpens and similar barriers around cots feature as usually insurmountable barriers to the younger characters in Rugrats, who are of crawling and toddling age. [Two kids, with very different hair style, are in a playground. A fence is visible in the background, and on the ground appear to be various items including a puddle or rug and toy blocks.] Scruffy-haired kid: Ugh don't you hate how parents are all "Eat your carrots" and "LOL, remember Rugrats and Doug? Share if you're a 90's kid!" [Caption below the panel:] The median age at first birth in the US is 25, which means the typical new mother is now a 90's kid.

xkcd Phone 3

xkcd Phone 3

https://www.xkcd.com/1549

https://www.explainxkcd.com/wiki/index.php/1549:_XKCD_Phone_3

[An image of a smartphone lying down, with many labels pointing to it. There is a black stripe across the top left corner of the phone. At the top right something is protruding from the side, like a volume control. There is a wrist band (only partly shown) attached to the middle of each side of the phone. Above the screen are several small features, below only a central square and on the bottom a socket. Clockwise from the top left the labels read:] 2 AA batteries (not included) Boneless Ear screen Heartbeat accelerator MobilePay money clip Siri, or whoever it was we put in here Instead of being on surface only, screen goes all the way through theknot.com partnership: Phone licensed to perform wedding ceremonies and does so at random Fingerprint randomizer USB E (hotswappable) Waterproof, but can drown Foretold by prophecy Runs natively Wristband Wireless discharging Magnetic stripe [Below the phone:] Introducing The xkcd Phone 3 We made another one®©™

This is the third entry in the ongoing xkcd Phone series which parodies common smartphone specs by attributing absurd or useless features to a fictional phone that sounds impressive but would actually be very impractical. The previous comic in the series 1465: xkcd Phone 2 was released over half a year before this one and the next 1707: xkcd Phone 4 was released almost a year later. 2 AA batteries (not included) A phrase usually shown on small, low-powered, electronic devices like remote controllers, and not on cellphones; which use lithium-ion batteries and need to be periodically recharged for continuous use. The apparently thin phone (according to the scale as judged by the wristband) would also preclude inserting AA batteries, unless a protruding battery compartment is hidden out of view on the back of the phone. Alternatively could mean two Anti-Aircraft (artillery) "batteries" which would be groups of light or medium artillery pieces or missiles (2 to 9 weapons per battery, depending on country, weapon system and organization). In any case, they would badly hamper the portability of the phone. [ citation needed ] Boneless Reference to meat or fish products being boneless, i.e. having all the bones removed, making it convenient to cook or eat. Phones do not typically have bones [ citation needed ] , so this is wholly unremarkable. A possible reference to the iPhone 6's reported problems with its chassis, where it could bend under pressure . Likely a reference to "Bone Conduction Microphones" implying that needing bones to work is a disadvantage and this phone has the feature of being "Boneless". xkcd Phone 4 was instead "seedless". Ear screen An overcomplicated term for a speaker, connecting a screen which emits light to send visual information and the portion of a speaker which vibrates to send auditory information. Comparing the two makes a speaker a screen for the ear. Could also be implying that there's a screen protecting the user's ear from the phone's internals, or the reverse. Heartbeat accelerator A mashup of heartbeat sensor and accelerometer. May be some sort of external pacemaker. If that's the case, it's worrying that it only accelerates, potentially causing a positive feedback (heart attack). It may also be the result of the phone being so exciting or frustrating that it increases its user's heart rate. MobilePay money clip While mobile pay is a form of payment involving electronic transfers via cellphone, this model includes a money clip; a way of holding physical bills together, which defeats the purpose of electronic payment. Because you can take cash wherever, this is a "MobilePay" using physical money. Siri, or whoever it was we put in here A joke on intelligent personal assistants. It also hints that Siri and the like are actual people, trapped inside of phones, which is not the case [ citation needed ] . Instead of being on surface only, screen goes all the way through A reference to surface screens. Possible reference to smartphones with screen display wrapping one or more edges, like Samsung Galaxy Note Edge or Samsung Galaxy S6 Edge, or dual-screen smartphones with screen on the back (usually e-ink) like YotaPhone 2, or smartphones with minimal bezel like e.g. Sharp AQUOS Crystal. Screen going all the way through would leave no place for innards of smartphone: processor, battery etc., and unless each layer is designed to be semi-transparent to see the inner voxels the inner displays would be unseeable anyway. theknot.com partnership - phone licensed to perform wedding ceremonies and does so at random theknot.com is a website that assists in all stages of wedding planning. Due to this partnering, the phone has apparently obtained legal status as a Justice of the peace capable of performing legally valid marriages. It exerts this capability randomly, however, so the phone's owner (or potentially any other unsuspecting bystander) could suddenly find themselves with a new spouse without their knowledge, generally an undesired effect [ citation needed ] . Whether this would result in unintentional bigamy or if the phone restricts itself to pairing up singles, or even enacts divorce first if necessary, is left unclear. May be a reference to how same-sex marriage was fully legalized in the United States just two weeks prior to the release of this comic. Fingerprint randomizer Presumably randomises the user's fingerprint, which may or may not be inconvenient depending on the intent of the user. It is not clear whether the device will change the person's fingerprint into a human-like fingerprint that is randomly selected from all possibilities, or if it completely mangles the fingerprint of the user. Either way, physically altering the user's finger to this degree will likely involve a painful process. Likely a cynical reference to fingerprint scanners, which are touted as password replacements. USB E (hotswappable) A USB port that makes fun of the three current systems, A, B, and recently C, by skipping D completely and jumping to E. The port presumably charges the phone and allows to transfer files like normal, but this kind lets you perform Hot swapping (replacing computer system components without turning the system off) with it, which has always been a feature of USB, so mentioning it is redundant at best. May be a reference to the eSATAp (Power over eSATA) hybrid port that is functioning as a USB and eSATA port at the same time. The Serial ATA bus interface has standardized hot swapping support. Waterproof, but can drown Perhaps a reference to Siri or the person trapped in the phone drowning, but the phone itself staying functional. This is another human-like function, which the first 2 XKCD Phone comics had. Foretold by prophecy Likely mocking people on the internet who attempt to predict when Apple will release their next device. Might also be a joke on many videogames or fantasy novels, in which the main character is 'the chosen one', because 'the prophecy' foretold it. Runs Natively Usually a description given to ported software, as this statement doesn't make any sense when referring to hardware (notable exceptions to the norm are few and far between). When software writers would like to run their apps on multiple platforms, they usually have three choices: re-compile the source code into each platform's codebase (often requiring tweaking to handle practical differences in resources between the systems); use a specially 'pre-portable' code that you can write once, run anywhere , such as Java, but requires a suitable interpreter to be written for each platform (and may still require code tweaks to absorb differences in implementations); create a specific emulator/virtual machine to allow existing code to 'see' the platform it was written for, despite the underlying system. Only the first option is 'running natively', often the most optimised and thus best-performing option, and is usually qualified such as "Runs <Software Name> natively", for particular packages full compiled upon that platform. It would also make little sense for the OS itself to be non-native, except when intentionally emulating another system (ideally on a more powerful system that can power past the inefficiencies of conversion and translation). Or, in this case, it may be that the phone has legs and can literally run. Wristband Probably mocking trending smart watches, this feature would not be very useful on a full-sized smart phone, as it would be uncomfortable to wear due to its size. Also possibly a follow-up to xkcd Phone 2 being described as a 'phone for your other hand', as the wristband would make it possible to have all three phones accessible at once. Wireless discharging Some modern smartphones use a system called "wireless charging," in which power is delivered to the phone without a wire. This phone, however, uses wireless technology to discharge the phone, which would be useless given that the phone needs power and removing power from its battery doesn't seem to help... May also refer to the standard behavior of the phone's antenna, which communicates wirelessly via EM radio waves, but discharges the battery in doing so. It could also be simply and literally describing the nature of all cell phones, and indeed all battery-powered electronic devices, to gradually use the battery (discharging) when there are no wires attached (wireless), since wireless also means no power cord is plugged in (and assuming the absence or non-use of the aforementioned wireless charging function, which this phone may not even have). Depending on the avenue of discharge, this may also be related to the heartbeat accelerator, accelerating the user's heartbeat by shocking them. Notably, a few recent flagship phones now have a built in Qi wireless charging pad, so other devices can charge from its battery; this is usually marketed as power-sharing but could also be called wireless discharging. Magnetic stripe Likely a dig at the NFC (near-field communication) wireless radio modules in many modern phones. NFC allows, among others functions, mobile payment. This magnetic stripe could be a cheap way to imitate payment functionality, but "compatible" with classic credit cards. Magnetic stripes are a data storage method used by devices such as credit cards and key cards to hold and transfer small amounts of information like key codes. Usually cellphones don't have them as they utilize more robust and protected ways to store and transmit data (such as NFC). The magnetic stripe shown would likely be unusable with current magnetic stripe readers due to the phone's thickness, in contrast to that of regular cards, thus breaking all imagined 'compatibility' arguments. It would also be very annoying as it seems to block part of the screen, albeit a small portion. However, some modern phones actually have Magnetic secure transmission which allows them to interface wirelessly with magstrip readers by simulating the magnetic field from a passing magnetic stripe. The phrase "We made another one®©™" is a reference to how phone companies release new phones very often, and the trademarks that surround the phone itself. The title text is a joke on guarantees and customer service. Usually the advertisement says that if the customer is not satisfied with the product, they'll refund the money and take the product back at no additional cost. In this case they guarantee the customer they'll send him/her home without charge; implying they won't fix or refund anything. Or that due to anticipated but unspecified faults of some kind, the phone's owner will need help to get back home when things go wrong, and probably be thankful for such assistance, in yet another example of a worryingly non-specific 'reassurance'. In addition, it says it would do so only AFTER thirty days, as opposed to the usual thirty-day return guarantee, which means you may be stuck with your phone for a month until you can be taken home yourself. [An image of a smartphone lying down, with many labels pointing to it. There is a black stripe across the top left corner of the phone. At the top right something is protruding from the side, like a volume control. There is a wrist band (only partly shown) attached to the middle of each side of the phone. Above the screen are several small features, below only a central square and on the bottom a socket. Clockwise from the top left the labels read:] 2 AA batteries (not included) Boneless Ear screen Heartbeat accelerator MobilePay money clip Siri, or whoever it was we put in here Instead of being on surface only, screen goes all the way through theknot.com partnership: Phone licensed to perform wedding ceremonies and does so at random Fingerprint randomizer USB E (hotswappable) Waterproof, but can drown Foretold by prophecy Runs natively Wristband Wireless discharging Magnetic stripe [Below the phone:] Introducing The xkcd Phone 3 We made another one®©™

Episode VII

Episode VII

https://www.xkcd.com/1550

https://www.explainxkcd.com/wiki/index.php/1550:_Episode_VII

[Black background with white letters in the style of the Star Wars logo with the subtitle in between the two words.] Star The Force Awakens Wars [Building in the desert, two persons are seen in the background, and Cueball is running in front of the building. Next to the building is a sign.] Sign: Tosche Station [A hooded man standing next to R2D2 has entered the building, and is seen in front of the opening portal with the desert in the background.] Hooded man: Hello. [Closeup of hooded man. The man has a mustache and a beard and thick black hair.] Hooded man: I’m here for those power converters. [Black background with white letters resembling movie credits.] Directed by J.J. Abrams

Sequels are often made to resolve pressing issues that are left unresolved in the original works. This comic was a humorous take on how the then-upcoming sequel in the Star Wars franchise might have resolved issues from a previous film in that series. In the first-produced movie of the series, Star Wars:Episode IV: A New Hope , Luke Skywalker 's uncle tells him to clean two newly purchased droids ( R2-D2 and C-3PO ). Luke complains that he had plans to pick up some power converters at Tosche Station . Luke is told to clean the droids first; however, while doing so, he discovers a message carried by R2-D2, starting him on a course of events that runs through the original trilogy. As a result, he never ultimately goes to Tosche Station. The conversation between Luke and his uncle, Owen Lars , is as follows: Uncle Owen: Luke! Take these two over to the garage will ya? I want ’em cleaned up before dinner. Luke: But I was going into Tosche Station to pick up some power converters! Uncle Owen: You can waste time with your friends when your chores are done. Now, come on. Get to it. Luke's line is one of many well-known lines from the series and is often-quoted as an example of how Luke is initially portrayed as a whiny teenager. By the end of the Episode VI:Return of the Jedi , Luke has grown into a mature and powerful Jedi, completing his transformation through the original trilogy. Star Wars Episode VII: The Force Awakens was, at the time of the comic's release, the upcoming seventh feature-length live-action film in the Star Wars series, and was the first since the rights to the franchise were sold by creator George Lucas to the Disney Company. It is a sequel to the original trilogy. Since creating the original trilogy, many of Lucas's decisions in respect of the franchise have been subject to fan criticism, including criticism of the quality of three prequel films Lucas produced beginning in 1999 (after a more than 15-year hiatus). The new seventh film was entrusted by Disney to producer/director J.J. Abrams, who in 2009 produced and directed the highly acclaimed (although still highly criticized by some fans) Star Trek reboot. Given all of this context, the new Star Wars film was as highly anticipated, or more highly anticipated than the prequel trilogy, and had a strong buzz around it. Much of the early buzz surrounded the nature of the new film's plot: For example, whether it would be a prequel or a sequel, and whether it would feature any of the original cast/characters. J. J. Abrams and others involved in the filming Star Wars Episode VII: The Force Awakens had appeared in a panel at San Diego Comic-Con the weekend prior to the comic's release to unveil details about the film. This is likely the impetus for the timing of this comic. This comic portrays Randall's own conception of what the sequel might have been. In his version of the movie, Luke returns home to Tatooine years later with R2-D2 to finish the errand that was interrupted. Luke goes to Tosche Station and says "I'm here for those power converters", thus completing this unresolved task from the first movie. The action is bookended by the opening and closing credits , suggesting this uneventful scene comprises the entire film. Therefore, the comic jokingly implies that getting the power converters was the most pressing of all the unresolved issues in the other films, and the most interesting upon which to base the sequel. In reality, this would likely be one of the least entertaining and most disappointing sequels that could possibly be made (perhaps second only to a version that had no reference to the previous films at all). Randall may have also been commenting that there are few if any unresolved issues in the Star Wars franchise that required revisiting and that the series should be left alone. Or he could have been making a joke about how sequels call back to elements of previous movies without fully considering the context. In this case, the farm he's buying those power converters for was destroyed more than thirty years ago. The title text alludes to another fantasy franchise, Lord of the Rings , and how Samwise Gamgee was similarly interrupted from a menial task of gardening and listening in on conversations outside Bag End by Gandalf and his quest to save the world at the start of the first film. The title text uses the term “dropping eaves” as Samwise did in his denial of eavesdropping in on the conversation between Frodo and Gandalf. In both cases, the issue of collecting power converters and Sam’s gardening duties were left unresolved in their respective stories and the main plot of the series is thoroughly concluded. [Black background with white letters in the style of the Star Wars logo with the subtitle in between the two words.] Star The Force Awakens Wars [Building in the desert, two persons are seen in the background, and Cueball is running in front of the building. Next to the building is a sign.] Sign: Tosche Station [A hooded man standing next to R2D2 has entered the building, and is seen in front of the opening portal with the desert in the background.] Hooded man: Hello. [Closeup of hooded man. The man has a mustache and a beard and thick black hair.] Hooded man: I’m here for those power converters. [Black background with white letters resembling movie credits.] Directed by J.J. Abrams

Pluto

Pluto

https://www.xkcd.com/1551

https://www.explainxkcd.com/wiki/index.php/1551:_Pluto

PLUTO Some of the features already identified in today's New Horizons image [Many marks on the image of Pluto follow:] Candy shell Frontal bone Grease stains Bugs JPEG plumes Full text of the wikipedia article on pareidolia Bullet holes New Netherlands Disputed territory Snake pit Tadpole Pluto dinosaur extinction crater Kuiper beltloops Serenity Ghost Dinosaur The good part Moon bud Scars from predator attacks Reset button Megaman Charging socket Cracks (beginning to hatch) Plug (inflating/deflating) Heart Mount Mons Coronary artery disease Debate hole Where we're putting all the people still arguing about Pluto's planet status Chocolate frosting Probably benign Vanilla frosting Dock connector Border of pride lands Hyena country Area missed during ironing Image credit: NASA/JHUAPL/SwRI - click for original

This comic was posted on Tuesday, July 14, 2015, in honor of the New Horizons deep space probe making its flyby at Pluto , thus breaking the typical Monday/Wednesday/Friday cycle for the xkcd comics. Also on this day he released the first what if? in over three months, and it was called New Horizons . Luckily it did not end up back on Earth, as depicted in 1532: New Horizons , released 1½ month before closest approach. Randall has taken one of the probe's images of Pluto, and outlined humorous examples of pareidolia on top of it. It can be compared to preliminary descriptions by geologists, e.g. New Horizons' best look at Pluto before close approach|The Planetary Society . The comic probably winks at Percival Lowell whose observatory photographed Pluto in 1915 "known" as Planet X. Unfortunately Percival Lowell is most famous for his drawings of the Canals on Mars which are widely misunderstood as channels based on wrong translations from Italian to other languages. The title text refers to the debate as to whether Pluto should be classified as a full or dwarf planet. This debate was particularly brought into the public eye and came to be seen as a matter of controversy, following the 2006 IAU definition of planet . The text may imagine that this debate winds on, with definitions being created and revised until a ridiculous state is reached whereby Pluto has a special class of celestial body named after it called a 'Pluto' but fails to fulfill the arbitrary criteria set up for it, and hence is called a 'dwarf Pluto'. There actually exist the terms Plutoid and Plutino , that relate directly to groups that Pluto belongs to, but see those pages for details of their use and usage. There has been a real naming conflict whilst generating those two categories, where Plutons was the name chosen initially, whereas Pluton is the usual name of Pluto in some languages. Candy shell Suggests Pluto is a confection, like Minmus . May also be a reference to the Mars candy bar. JPEG plumes The JPEG image format has the common issue of slightly distorting an image with Compression artifacts . The artifacts shown here do not appear in the official version of this image, but all data sent from New Horizons is compressed and artifacts are common — the full resolution images will be submitted to earth over the next 16 months. There have been tweets about people seeing plumes associated with active volcanoes and the like, which were explained as being artifacts. Frontal bone Interpreting Pluto as a head, the frontal bone could be the light-colored region next to the darker top, just above the north pole facing to us. Grease stains The area above Pluto's north pole is attributed to grease. Bugs Could refer to possible extraterrestrial life on Pluto in the form of insects , or "bugs". In the animated TV series Roughnecks: Starship Troopers Chronicles , an adaptation of Robert Heinlein's novel Starship Troopers , the first battles with the alien "Bugs" took place on Pluto. Maybe it also refers to a software bug at the probe. Bullet holes A string of small round features which Randall suggests was the result of Pluto getting shot repeatedly, probably by meteorites. New Netherlands Reference to the what if?, Drain the Oceans: Part II , about draining the Earth's oceans onto Mars. In the previous what if?, Drain the Oceans , the Netherlands took over the Earth once their problem with the risk of flooding disappeared. And then they continued to issue forth from the portal that drained the oceans on Earth pouring them onto Mars, to claim Mars as New Netherlands. Presumably, something similar happened on Pluto. This was already again references in both an entry in the table and in the title text of 1555: Exoplanet Names 2 . Disputed territory Since the base photograph is identified as "today's New Horizons image," this indicates that a section of Pluto has immediately become the subject of some controversy, possibly a territorial claim or one of several references to the fact that Pluto was demoted from full planet status in 2006. Snake pit A generic map hazard. Full text of the Wikipedia article on pareidolia Pareidolia is the human brain's tendency to see patterns where they don't exist. While probably a reference to Pluto's heart, the joke is also recursive: You'd be seeing the text of a Wikipedia article explaining to you that you couldn't actually be seeing the text of a Wikipedia article. Tadpole One of a number of pareidolic features Randall has outlined. Kuiper Belt loops The Kuiper belt is a region in our solar system that contains an unknown amount of icy bodies, one known is Pluto. Randall jokingly refers to Kuiper Belt as the same kind of belt that's used to fasten clothing and identifies features on Pluto's surface as loops for the belt. Serenity An outline of the Firefly -class spaceship Serenity , which was the titular vessel from the 2002 TV series Firefly . One of a number of pareidolic features Randall has outlined. Dinosaur Nobody can see a dinosaur unless Randall did do this painting on Pluto's surface. And a complex comic needs at least one dinosaur. The good part A section of Pluto that is objectively better than the rest. Moon bud This could be interpreted as a moon growing/emerging out of Pluto, as a bud is "a compact knob-like growth". A round growth is seen at the location marked, resembling a small, emerging moon. Ghost A reference to the classic video game Pacman , wherein the primary antagonists are one of four Ghosts. The Ghost on Pluto appears to have a mouth, however, unlike most depictions of the Pacman Ghosts. One of a number of pareidolic features Randall has outlined. Pluto dinosaur extinction crater Suggests Pluto had dinosaurs and lost them the same way Earth did. Heart One of a number of pareidolic features Randall has outlined, and the only one (currently) also informally named as such by NASA. Coronary artery disease Also known as ischemic heart disease , which causes degradation of heart tissue. The region identified in the comic looks less 'healthy' (is darker and more ragged) compared to the rest of the 'Heart', which Randall suggests is caused by the disease. Mount Mons Referring to the general practice of naming extraterrestrial mountains "X Mons" (e.g. Olympus Mons , a mountain on Mars and the largest mountain in the Solar System), as well as naming terrestrial mountains "Mount X". Since "mons" is Latin for "mountain", the feature's suggested name translates as "Mount Mountain". Charging socket A terrain feature suitable for connecting an outside source of electricity for the benefit of implied internal batteries. Compare "dock connector," below. Cracks (beginning to hatch) Implying that Pluto is some manner of a giant egg. Possibly a reference to the Doctor Who episode Kill the Moon , in which the Moon is revealed to be an egg from which a monster is hatching. A 2014 article from The Onion , "Moon Finally Hatches," makes the same joke. Also possibly a reference to The Light Fantastic , a Discworld novel in which similar objects are revealed to be the eggs of the world turtle. A similar idea appeared in Jack Williamson's 1934 short story "Born of the Sun". Plug (inflating/deflating) Inflatable balls often have a "plug" or opening to insert a needle to inflate or deflate them. Scars from predator attacks Since it's all-caps, we can't tell if "PREDATOR" is a proper noun, but this is possibly a reference to the movie series Predator , about a race of aliens who hunt other beings for sport. Alternatively, a planetary predator (such as comic book villain Galactus ) may have previously scarred Pluto. Reset button The structure indicated is a small black dot (at least at this distance this picture was taken). Reset buttons on home electronics are often small buttons or holes used to reset the software of the electronic device. Megaman One of a number of pareidolic features Randall has outlined, this one in the shape of a popular video game protagonist. Debate Hole - Where we're putting all the people still arguing about Pluto's planet status Pluto was reclassified as a dwarf planet rather than a planet following the latter term's controversial redefinition in 2006 by the International Astronomical Union . Arguments about the classification continue to pop up. The same argument is referenced in the title text. The name implies a proposal to put all the people still arguing about it in this hole on Pluto. This proposal further implies that the continued debate is very annoying by 2015, except perhaps to the debaters themselves. Area missed during ironing The area indicated is near the terminator and shows some intriguing topographic relief. Probably Benign A neoplasm or tumor is an abnormal growth of tissue. Randall is suggesting that the abnormal region near the heart has been evaluated by a doctor and determined to be benign . Chocolate frosting Suggests the discrepancy in color over Pluto's surface may be a function of what cake frosting was used where. This area is the "dark spot" at the head of the "whale" ( http://www.nytimes.com/interactive/2015/07/14/science/space/pluto-flyby.html ). The so-called "whale's tail" ( http://www.nbcnews.com/science/space/find-heart-whale-new-horizons-picture-pluto-n388816 ), is on the other hemisphere and is not visible in this image, it lies east about 90 degrees from the chocolate frosting/dark spot here. Vanilla frosting As above, suggests the discrepancy in color over Pluto's surface may be a function of what cake frosting was used where. Border of pride lands A reference to the Disney animated feature The Lion King. In the movie, the Pridelands is the bright and prosperous region ruled by the Lion King while a dark territory beyond its border is controlled by hyenas. Hyena country A continuation of the Lion King reference above. Dock connector From the point of view of the photograph, this feature of Pluto is at the planet's "bottom," where iPod dock connectors are. Compare "charging socket," above. PLUTO Some of the features already identified in today's New Horizons image [Many marks on the image of Pluto follow:] Candy shell Frontal bone Grease stains Bugs JPEG plumes Full text of the wikipedia article on pareidolia Bullet holes New Netherlands Disputed territory Snake pit Tadpole Pluto dinosaur extinction crater Kuiper beltloops Serenity Ghost Dinosaur The good part Moon bud Scars from predator attacks Reset button Megaman Charging socket Cracks (beginning to hatch) Plug (inflating/deflating) Heart Mount Mons Coronary artery disease Debate hole Where we're putting all the people still arguing about Pluto's planet status Chocolate frosting Probably benign Vanilla frosting Dock connector Border of pride lands Hyena country Area missed during ironing Image credit: NASA/JHUAPL/SwRI - click for original

Rulebook

Rulebook

https://www.xkcd.com/1552

https://www.explainxkcd.com/wiki/index.php/1552:_Rulebook

[Cueball and Megan are standing with a dog wearing jersey number 9, Ponytail and Hairy are facing them holding a rulebook. The horizon is visible behind them.] Ponytail: There's nothing in the rulebook that says we can't kill and eat your dog.

This comic is a direct reference to the film Air Bud . In the film, a golden retriever becomes the star player on a basketball team. The opposing team contests the legality of having a dog as a player, but the referee, having reviewed the rulebook, responds "Ain't no rule says a dog can't play basketball." Here, the opposing team turns the rulebook loophole against the first team . Because rulebooks are considered the final arbiter of decisions in most sports, Ponytail suggests that, since it isn't explicitly prohibited, her team is allowed to kill and eat the dog. Randall is using this logical fallacy to highlight the absurdity of the plot of Air Bud and other similar movies in which ordinary animals take on human roles. At the same time, Randall has created an absurd and anticlimactic premise for such a movie, and he may be making a more general commentary on Hollywood 's habit of making movies by combining basic tropes that, by themselves, tend to do well in the box office. The title text acknowledges that killing and eating the dog would result in a foul (interfering inappropriately with other players), but the benefit of committing the foul (the star player being dead and out of the game) would be worth the resulting penalty (giving the other team a couple of free throws). This of course ignores any local laws that could cover the proposed killing, such as animal cruelty laws. Randall is poking fun at the common practice of intentional fouls, something that happens particularly often in basketball. Although a foul is by definition against the rules, a team may deliberately break those rules and accept the penalty in order to gain some perceived advantage. For example, in association football (soccer), a player may intentionally foul an opposing player with a strong attack to allow his team to regroup and increase its defensive position, starting with blocking the resulting free kick. In basketball, an intentional foul can stop the clock and turn over the ball, or may simply give the team time to rest and/or discuss strategy that it otherwise may not have had. The dog in the comic is wearing a jersey with the number 9. In Air Bud , the dog wore a jersey with "K" on one side and "9" on the other, forming "K-9", a popular shortening of the word "canine". Randall previously parodied the "animal-as-player" loophole in 115: Meerkat . Rule books are also mentioned in 330: Indecision , 393: Ultimate Game , and 1593: Play-By-Play . [Cueball and Megan are standing with a dog wearing jersey number 9, Ponytail and Hairy are facing them holding a rulebook. The horizon is visible behind them.] Ponytail: There's nothing in the rulebook that says we can't kill and eat your dog.

Public Key

Public Key

https://www.xkcd.com/1553

https://www.explainxkcd.com/wiki/index.php/1553:_Public_Key

[In the first panel, Cueball is sitting in a chair and is using a laptop.] Cueball (thinking): I've been posting my public key for 15 years now, but no one has ever asked me for it or used it for anything as far as I can tell. [This is followed by two beat panels where Cueball just sits there. doing nothing, not even thinking.] [In the final panel he again uses his laptop and thinks.] Cueball (thinking): Maybe I should try posting my private key instead.

In public-key cryptography , two keys are generated for a user. The public key can be used to encrypt messages, but not decrypt them. The private key is necessary for decryption, and as its name implies, is meant to be used solely by the user. Since the public key is initially designated to be shared, anyone who has that key can send the user an encrypted message that only the user can decrypt. Cueball has been following this rule, but he notices that it appears nobody has ever used his public key for anything. He contemplates sharing his private key, which he believes would generate more interest in him personally. However, he appears to overlook the fact that doing so would allow anyone to decrypt messages sent to him, thus defeating the entire purpose of encryption. (Although some systems can confirm the message sender by having a secret encryption key and a public decryption one, though this is negated again if both keys are released.) The title text refers to another feature of Public-key cryptography: In addition to assuring that certain messages can only be read by a specific key owner, it can also assure that certain messages could only have been written by a specific key owner, by "signing" it using the private key. Anyone can read a signed message, but readers with the public key can then verify that the owner of the private key wrote (or at least signed) the message, rather than someone pretending to be the owner. If Cueball published his private key, then anybody could sign any message as him, effectively impersonating him and also defeating the purpose of encryption. Crowdsourcing is the term used for delegating work or tasks to a largely volunteered and uncontrolled set of people on the Internet. It is similar in concept to outsourcing , in which work is delegated to an external source of labor, typically a company in a foreign country. Famous instances of crowdsourcing include reCAPTCHA (in which users both verify they are human and help digitize words and phrases in books that digitization software cannot understand) and a farm in the UK in which ordinary Internet users make decisions about how the farm is run. When Cueball first created the key pair, he imagined it would be something he used from time to time, for reading messages only intended for him or for sending "signed" messages. Since nothing of the sort happened, he imagines releasing both keys might cause some activity, and at this point he is happier with a "bad" outcome than with a boring one. Randall previously ironically mentioned a public key in 370: Redwall . [In the first panel, Cueball is sitting in a chair and is using a laptop.] Cueball (thinking): I've been posting my public key for 15 years now, but no one has ever asked me for it or used it for anything as far as I can tell. [This is followed by two beat panels where Cueball just sits there. doing nothing, not even thinking.] [In the final panel he again uses his laptop and thinks.] Cueball (thinking): Maybe I should try posting my private key instead.

Spice Girls

Spice Girls

https://www.xkcd.com/1554

https://www.explainxkcd.com/wiki/index.php/1554:_Spice_Girls

Cueball: Your turn: Can you name all of the Spice Girls? Megan: Hmm… Hearing Spice, Vision Spice, Smell Spice, Touch Spice, Taste Spice? Cueball: That’s senses. Megan: Denial Spice, Anger Spice, Bargaining Spice, Depression Spice, Acceptance Spice. Cueball: Stages of grief. Megan: War Spice, Famine Spice, Plague Spice, Death Spice? Cueball: You're not even trying. Megan: No, wait, I can get this for real. Uhh… Megan: Pog Spice, Story Spice, Sarah Spice, Gender Spice, Baleen Spice? Cueball: …Close enough.

Cueball and Megan are apparently playing a game in which they name all of the elements in some category. Cueball asks Megan to name all of the Spice Girls , a pop group whose nicknames were Instead, Megan winds up making up names by tacking "Spice" onto words from other, completely unrelated categories: This seems to be a continuation of 1417: Seven , where Megan asks Cueball to name the seven dwarfs. Apparently Megan confuses different sets of five (or four when she is not trying) which may be compared to the way Cueball mixes items from different sets of seven, thus not mentioning a full set, but just seven items from seven different sets of seven. The title text has the correct "first" names of the Spice Girls, but replaces the "Spice" part of their names with "Extinction" to associate them with Earth's five mass extinctions . The five actual worst mass extinctions are: Randall previously referenced the Spice Girls in 1511: Spice Girl (more specifically, using "Which Spice Girl Are You?" as an example of online personality quizzes). And already in the next comic 1555: Exoplanet Names 2 he suggest to give five exoplanets around the same star the five nicknames. Cueball: Your turn: Can you name all of the Spice Girls? Megan: Hmm… Hearing Spice, Vision Spice, Smell Spice, Touch Spice, Taste Spice? Cueball: That’s senses. Megan: Denial Spice, Anger Spice, Bargaining Spice, Depression Spice, Acceptance Spice. Cueball: Stages of grief. Megan: War Spice, Famine Spice, Plague Spice, Death Spice? Cueball: You're not even trying. Megan: No, wait, I can get this for real. Uhh… Megan: Pog Spice, Story Spice, Sarah Spice, Gender Spice, Baleen Spice? Cueball: …Close enough.

Exoplanet Names 2

Exoplanet Names 2

https://www.xkcd.com/1555

https://www.explainxkcd.com/wiki/index.php/1555:_Exoplanet_Names_2

[Black Hat points with a stick at a slide showing an image of a planet with unknown features marked by questions marks.] Kepler-452b Black Hat: NASA has announced the discovery of a (super-)Earth-sized planet in the habitable zone of a sun-like star. Black Hat: I suggest we name this planet "Pluto", both to celebrate the great work by the New Horizons team, and to make the stupid "Is Pluto a planet" debate a little more confusing While we wait to hear from the IAU, here's a revised and updated list of planet name suggestions (see xkcd.com/1253) New or updated entries in red [The table is in three separate columns. There is a small arrow pointing at the second column, named "Planet", indicating the planet's name corresponding to the star at the first row. The third column shows the planet name suggestions.] Star Planet Suggested Name Gliese 667 b Space Planet c PILF d A Star e e'); DROP TABLE PLANETS;-- f Blogosphere g Blogodrome h Earth Tau Ceti b Sid Meier's Tau Ceti B c Giant Dog Planet d Tiny Dog Planet e Phil Plainet f Unicode Snowman Gliese 832 b Asshole Jupiter c Waterworld starring Kevin Costner Gliese 581 b Waist-deep Cats c Planet #14 d Ballderaan e Eternia Prime f Taupe Mars g Jelly-Filled Planet Epsilon Eridani b Skydot c Laser Noises Gliese 176 b Pandora c Pantera Kepler-61 b GoldenPalace.com Groombridge 34A b Hot Mess Kepler-442 b Seas of Toothpaste Gliese-442 b This one weird planet EPIC-201367065 b Sulawesi c Huge Soccer Ball d Geodude Kepler-296 b Kerbal Space Planet c A$aplanet d Jurassic World e This Land f Springfield HR 7722 b Betelgeuse c Beetlejuice EPIC 201912552 b Netherlands VI Gliese 3293 b Antispit c Google Earth d Planet of the Apes (disambiguation) Kepler-283 b ˈjʊərənəs c jʊˈreɪnəs Upsilon Andromedae b Fourthmeal c Stampy d Moonchild e Ham Sphere HD 20794 b Cosmic Sands c Legoland d Planet with Arms HD 85512 b Lax Morality HD 40307 b Good Planet c Problemland d Slickle e Spare Parts f New Jersey VI g How Do I Join the IAU Gliese 163 b Neil Tyson's Mustache c [email protected] d Hair-Covered Planet Pi Mensae b Moon Holder HD 189733 b Permadeath Kepler-22 b Blue Ivy KOI-2474 b Store-Brand Earth Kepler-437 b Unicorn Thresher KOI-2418 b Spherical Discworld Kepler-438 b Emergency Backup Earth KOI-3010 b Feeeoooooooop Kepler-442 b Liz 82 Eridani b Horsemeat Surface c The Moon d Constant Saxophones HD 102365 b Little Big Planet Gliese 180 b Dune c Arrakis Fomalhaut b Swarm of Bees Kepler-62 b Sporty c Baby d Scary e Ginger f Posh HD 69830 b Planet.xxx c Novella d Sexoplanet Gliese 682 b Verdant Hellscape c Unsubscribe Kepler-452 b Pluto A Unicode snowman is also referenced in Randall's book What If , where it is keymapped to a laptop. Randall has also poked fun at the Netherlands in Drain the Oceans, where the Netherlands, no longer worrying about a cataclysmic flood, take over the world, and in Drain the Oceans: Part II, where the Netherlands use the portal to colonize Mars. See the https://what-if.xkcd.com/archive/ for more details.

This comic is a continuation of 1253: Exoplanet Names , and was published the day after NASA announced the discovery of a number of planets, including a planet called a cousin to Earth, Kepler-452b . Black Hat proposes naming it Pluto , to commemorate the flyby of the dwarf planet of that name by NASA's New Horizons earlier the same month. He admits this alternative to end the discussion about the status of Pluto, which is subject to debate among both scientists and laypeople over whether-or-not it should be considered a planet. Pluto was considered a planet for a long period of time until, in 2005, the International Astronomical Union (IAU) created a new definition for the word 'planet' designed to exclude Pluto and similar objects, resulting in much debate (The IAU is the organization that takes responsibility for naming celestial bodies like planets, stars, and much more). It may appear that, with Black Hat's suggestion, the answer to the question "is Pluto a planet?" will therefore always be "yes", regardless of the status of the Pluto in our Solar System according to the IAU. However the same IAU official definition that excludes Pluto also states that a 'planet' has to orbit our sun, so according to the IAU, nothing in this comic is a planet (the IAU definition only allows them to be exoplanets , which, like dwarf planets, are not planets). Hence, the debate indeed becomes 'a little more confusing'. This is in line with Black Hat's characterisation as a mischief-maker. The title text is referring to the planet name entry Netherlands VI for the star EPIC 201912552 . Randall thus continues his references to the Dutch people taking over the world and then the universe after the earth's oceans has been drained and transported to Mars. This happens in two consecutive What if? 's, Drain the Oceans and Drain the Oceans: Part II , was referenced in Dropping a Mountain , and was referenced again the week before this comic in 1551: Pluto . Due to a drain in the Earth's ocean the Netherlands does not have to worry about getting flooded anymore and since it now does not have to use all its resources preventing floods, it can use these to conquer the world (including Antarctica becoming South Netherlands). Then it takes on Mars (which becomes New Netherlands), and then a section of Pluto (again calling it New Netherlands). There is also a possible reference to 1519: Venus , but that comic has no direct relation to the conquests of the Dutch people like in the other three references. It should be mentioned, that New Netherland was actually a Dutch colony with New York City , formerly known as New Amsterdam , as its capital. So the name "New Netherlands" is "historically correct", while "Netherlands VI" isn't. In the title text Randall mentioned that he will continue with this Netherlands joke driving it so far into the ground, (i.e. way beyond the point where it stops being funny), that they (the Dutch people) will have to build levees (or dykes) around it to keep the sea out - thus making it funny again... By forcing the Dutchmen to build new levees for this reason, the whole issue with their conquest of the world will be over before it happens. This table explains each entry in the comic table. The "Status" column refers to the comic 1253: Exoplanet Names , and indicates if the entry was already in that version (Old), if it is an addition since then (New) or if the entry has been updated (Update). [Black Hat points with a stick at a slide showing an image of a planet with unknown features marked by questions marks.] Kepler-452b Black Hat: NASA has announced the discovery of a (super-)Earth-sized planet in the habitable zone of a sun-like star. Black Hat: I suggest we name this planet "Pluto", both to celebrate the great work by the New Horizons team, and to make the stupid "Is Pluto a planet" debate a little more confusing While we wait to hear from the IAU, here's a revised and updated list of planet name suggestions (see xkcd.com/1253) New or updated entries in red [The table is in three separate columns. There is a small arrow pointing at the second column, named "Planet", indicating the planet's name corresponding to the star at the first row. The third column shows the planet name suggestions.] Star Planet Suggested Name Gliese 667 b Space Planet c PILF d A Star e e'); DROP TABLE PLANETS;-- f Blogosphere g Blogodrome h Earth Tau Ceti b Sid Meier's Tau Ceti B c Giant Dog Planet d Tiny Dog Planet e Phil Plainet f Unicode Snowman Gliese 832 b Asshole Jupiter c Waterworld starring Kevin Costner Gliese 581 b Waist-deep Cats c Planet #14 d Ballderaan e Eternia Prime f Taupe Mars g Jelly-Filled Planet Epsilon Eridani b Skydot c Laser Noises Gliese 176 b Pandora c Pantera Kepler-61 b GoldenPalace.com Groombridge 34A b Hot Mess Kepler-442 b Seas of Toothpaste Gliese-442 b This one weird planet EPIC-201367065 b Sulawesi c Huge Soccer Ball d Geodude Kepler-296 b Kerbal Space Planet c A$aplanet d Jurassic World e This Land f Springfield HR 7722 b Betelgeuse c Beetlejuice EPIC 201912552 b Netherlands VI Gliese 3293 b Antispit c Google Earth d Planet of the Apes (disambiguation) Kepler-283 b ˈjʊərənəs c jʊˈreɪnəs Upsilon Andromedae b Fourthmeal c Stampy d Moonchild e Ham Sphere HD 20794 b Cosmic Sands c Legoland d Planet with Arms HD 85512 b Lax Morality HD 40307 b Good Planet c Problemland d Slickle e Spare Parts f New Jersey VI g How Do I Join the IAU Gliese 163 b Neil Tyson's Mustache c [email protected] d Hair-Covered Planet Pi Mensae b Moon Holder HD 189733 b Permadeath Kepler-22 b Blue Ivy KOI-2474 b Store-Brand Earth Kepler-437 b Unicorn Thresher KOI-2418 b Spherical Discworld Kepler-438 b Emergency Backup Earth KOI-3010 b Feeeoooooooop Kepler-442 b Liz 82 Eridani b Horsemeat Surface c The Moon d Constant Saxophones HD 102365 b Little Big Planet Gliese 180 b Dune c Arrakis Fomalhaut b Swarm of Bees Kepler-62 b Sporty c Baby d Scary e Ginger f Posh HD 69830 b Planet.xxx c Novella d Sexoplanet Gliese 682 b Verdant Hellscape c Unsubscribe Kepler-452 b Pluto A Unicode snowman is also referenced in Randall's book What If , where it is keymapped to a laptop. Randall has also poked fun at the Netherlands in Drain the Oceans, where the Netherlands, no longer worrying about a cataclysmic flood, take over the world, and in Drain the Oceans: Part II, where the Netherlands use the portal to colonize Mars. See the https://what-if.xkcd.com/archive/ for more details.

The Sky

The Sky

https://www.xkcd.com/1556

https://www.explainxkcd.com/wiki/index.php/1556:_The_Sky

[Cueball and Megan are standing looking upward with in a small frame a light blue background.] Cueball: I like the sky. Megan: Yeah. [Zooms out to show a blue evening sky, the sun must be setting to the left and a streak of yellow and orange clouds goes from top left to bottom right. The sky/clouds get darker further to the right and several stars are visible behind the clouds on the indigo blue sky in the top right corner. There are also some gray clouds low over the horizon. Cueball and Megan standing to the far left Below them and the sky from the horizon and down there is a thick a black slab taking up about a sixth of the frame height.] Megan: It's one of my favorite halves.

In this comic Cueball and Megan admire a majestic sky on a beautiful day. This is one of the few comics where the scenery is drawn entirely in color, adding to the feeling of awe and natural wonder. The lighting on the clouds and the night sky in the upper corner suggest that this is either at sunset or sunrise, with the sun at the horizon outside the left part of the image. The picture is drawn to show the ever changing beauty of the many different stages of the sky rather than to be 100% realistic, as it would not be possible to see stars as clearly as shown, if the sun is still illuminating the clouds in front of them. When the sun sets or rises the light produces many different colors which can often be breathtaking to witness. The pouch shaped cloud formations are called mammatus clouds and are usually associated with nearing of bad weather. The comic, however, already start in a small panel, with uniform sky colored light blue background, above the large drawing described above. In this image Cueball says to Megan that he likes the sky and Megan agrees. Megan first elaborates on her feelings in the large image where the zoom out is so large that they have both become small and insignificant characters in the bottom left corner, dwarfed by the sky and cloudscape, with the ground a broad dark band beneath them. Megan makes a statement about the sky: It's one of my favorite halves . She thus indicates that she has more than one favorite halves. As there are only two halves this thus implies that Megan likes both halves, i.e. she likes everything. Her statement is thus a tautology because it implies that the other half is also a favorite and there are no other segments that would not be among her favorites. There are several xkcd comics about tautology, e.g. 703: Honor Societies , 870: Advertising and 1310: Goldbach Conjectures . In 1368: One Of The one of is also used in a similar way as there is really no other that that one in that comic, whereas here there are no other that has not be included. A very similar sentence is also used in the title text of 1524: Dimensions where the sentence, I would say time is definitely one of my top three favorite dimensions . This also makes very little sense as there are four dimensions with time, and the other three are indistinguishable as they are just three randomly chosen but orthogonal directions in space. Taken at face value, given that the image depicts half open sky and half clouds, the other half could be taken to mean the clouds covering half of the sky. Or it could be the sky and the dark Earth, the other half beneath their feet. That it is the latter becomes evident in the title text. In the title text Megan continues her comment as she states that her other favorite half has some cool objects in it. She then lists three types of objects: From this it is thus clear that it is not the clouds vs. the sky she's referring to but rather the sky vs. something down on Earth. Weather the clouds are considered part of the sky or just blocking the sky could be something Megan and Cueball would disagree about. See below. Based on these three items the other half could either be the entire Earth , just the solid ground or only the oceans . All three mentioned objects can be found both on land and in the oceans. Shipwrecks may be associate with oceans, but they are also often stranded on the shore. Snakes are mainly associated with land, but there are several snakes that live in the ocean. But the last part of the title text takes both the ground and the sea out of the equation, as it states that if those three objects where moved out of the way the other half would also have more sky. As Earth is round (and made from rock, most of them melted in the outer core ) then if you "moved all those rocks out of the way" you would see the sky below on the other side. This leads to the realization that the two halves are indeed the Sky and the Earth (or Heaven and Earth). The title text is thus a subversion as it may be switching the readers focus of what the other half may be, as seen from only the large image (clouds, stars or the ground). Beyond the blue sky above there is just the dark night sky of outer space . If it where not for the Earth the blue sky would not exists as it is formed by the air following the gravity and curvature of the earth. So if you would moved the entire Earth out of the way you would also move the blue sky with it and you would only see a similar dark night sky, with lots of stars like those in the top left corner. Of course if it was not the entire Earth, but just those rocks directly beneath Megan that was moved, then in principle she would be able to see the blue sky on the other side of Earth, But as she is saying moved all those away , it indicates that Megan really means the entire Earth. This last part of the title text thus shows that Megan may be thinking rather of the night sky, and given that there are also stars visible in the top right corner, she could have assumed Cueball also referred to the sky like this rather than the majestic display of clouds and colors. Of course that would be weird, but that's where the comedy occurs because that was unexpected, and it would be typical Megan and/or Randall . If Megan is also interested in astronomy then she would prefer a dark cloudless sky with stars. And by focusing on the fact that if the Earth was removed there would only be dark sky (empty space) around her on all sides, this may be one of her other often seen strange preferences. (Those are often used by one of the characters in Randall's comics). It is well know from xkcd that Randall really loves astronomy and looking at the night sky. So seen from this perspective, there would still be plenty of sky even if the Earth where removed completely. However, there would not be any clouds or nice colors or any humans or other lifeforms around to admire those astronomical objects. The title text also indicates that although the other half also is one of Megan's favorites, it is mainly the shipwrecks (the oceans) and the snakes (life forms) that she considers when thinking of this half. The rest is just rocks (the Earth). Taking into account how many different things that are on "that other half", why did Randall then choose to mention those two? Only he will know, but maybe indeed to focus on the oceans and their life forms or any life. [Cueball and Megan are standing looking upward with in a small frame a light blue background.] Cueball: I like the sky. Megan: Yeah. [Zooms out to show a blue evening sky, the sun must be setting to the left and a streak of yellow and orange clouds goes from top left to bottom right. The sky/clouds get darker further to the right and several stars are visible behind the clouds on the indigo blue sky in the top right corner. There are also some gray clouds low over the horizon. Cueball and Megan standing to the far left Below them and the sky from the horizon and down there is a thick a black slab taking up about a sixth of the frame height.] Megan: It's one of my favorite halves.

Ozymandias

Ozymandias

https://www.xkcd.com/1557

https://www.explainxkcd.com/wiki/index.php/1557:_Ozymandias

[Ponytail, with her arms stretched out, is addressing Cueball.] Ponytail: I met a traveler from an antique land who said: "I met a traveler from an an- tique land, who said "I met a traveler from an antique land, who said "I met...

Ponytail is reciting the opening of " Ozymandias " by Percy Bysshe Shelley (see text below). However, instead of continuing on with the poem, Ponytail is going through a recursion where the information is always being quoted from "a traveler from an antique land" who recounts what they were told by a similar traveler from another antique land. The title text once again plays with recursion, but instead of it being a string of travelers talking about travelers, it is a string of pedestals that are quoting pedestals. In the original poem, the text on the pedestal is itself recounted as part of the traveler's story, so there are already two levels of quotation, and the pedestal's inscription describes Ozymandias as the "king of kings", which, being itself a recursion, gives rise to the comic's joke. The poem Ozymandias is about the last vestiges of a once-great civilization that has since been lost to history. However, the poem itself, like the statue it describes,can be thought of as a pinnacle of achievement for its civilization- in this case, English civilization. So it is entirely possible that one day, after the fall of this civilization, the poem will fill the same role for it that the statue filled for Ozymandias' civilization, and would therefore be referenced by a traveler from an antique land who stumbled across it. The fact that Ponytail is now telling Cueball the story of this recursion implies that she is yet another layer of this recursion and is herself "a traveler from an antique land." The quotes are not nested properly, as they never end. So there is only the starting quotation mark (") for each quote. If she ever finishes there would be one closing quotation mark for each quote in the recursion at the end of her sentence. See 859: ( . The poem is a sonnet written in iambic pentameter , 10 syllables to a line (note that traveler should be read as trav'ler with only two syllables. Also note that it was originally written in British English where it was spelled with two l's as traveller ). The fragment quoted in the comic consist of the first line and two syllables of the second line of the original poem. The way Ponytail recites her version of the poem in the comic, each line continues to be iambic pentameters (which is the reason for the hyphenation of an-tique between 2nd and 3rd line). However the fourth and last line stops two syllables short, but would have continued as indicated by... Perhaps Randall did this to avoid finishing in mid word ("a trav-"). The title text quotes exactly one line, the 9th line or the first line of the second part of the poem, also stopping during the fourth repetition, although after just one word the fourth time, also with... to indicate that this goes on and on and... The poem "Ozymandias" is mentioned on pages 169 and 170 of the book Recursive Desire: Rereading Epic Tradition by Jeremy M. Downes. A similar joke was used in 785: Open Mic Night I met a traveller from an antique land Who said: "Two vast and trunkless legs of stone Stand in the desert. Near them, on the sand, Half sunk, a shattered visage lies, whose frown, And wrinkled lip, and sneer of cold command, Tell that its sculptor well those passions read Which yet survive, stamped on these lifeless things, The hand that mocked them and the heart that fed: And on the pedestal these words appear: 'My name is Ozymandias, king of kings: Look on my works, ye Mighty, and despair!' Nothing beside remains. Round the decay Of that colossal wreck, boundless and bare The lone and level sands stretch far away." [1] [Ponytail, with her arms stretched out, is addressing Cueball.] Ponytail: I met a traveler from an antique land who said: "I met a traveler from an an- tique land, who said "I met a traveler from an antique land, who said "I met...

Vet

Vet

https://www.xkcd.com/1558

https://www.explainxkcd.com/wiki/index.php/1558:_Vet

[Megan arrives with a pet carrier, Cueball stands at a desk as a veterinarian, and Hairy is waiting behind a rope, standing next in line with a dog on a leash and a pet carrier.] Megan: There's something wrong with my dog. He keeps crawling around eating dirt. [Cueball holds the content of Megan's pet carrier, a flat disk. She is standing behind the desk with the carrier on the desk.] Cueball: This is a Roomba. Megan: Well, he's a mix. Megan: Probably some Roomba in there. [The Roomba now lies on the table next to the carrier between the two.] Cueball: A Roomba is not a pet. Megan: You're right. It's wrong to keep a beautiful creature like this in a house. [Megan is outside left to a tree, arms up in the air, encouraging the Roomba to drive away.] Megan: Go! Megan: Be free! Roomba: Whirrr

Roomba is a brand of domestic cleaning robots manufactured by the company iRobot . The robots are designed to automatically vacuum floors. Although these robots are controlled by a quite simple software without any artificial intelligence, some owners tend to humanize them in the same way that others humanize their pets. There are several other comics related to a Roomba. Megan presents a pet carrier to Cueball the veterinarian assistant. She says that her "dog" is “crawling around eating dirt”, which sounds like certain types of behavioral problems one encounters in dogs, but is precisely what Roombas are made for. (However, the vacuum bag may need to be cleaned.) The vet then comments that it is a Roomba, to which Megan responds that the device (which has nothing to do with an animal) is a cross-breed, and agrees that there probably is “some Roomba” in it. She thus acknowledges the existence of Roombas, but still treats them as if it were an animal. It's common to talk about domestic dogs this way, but cross-breeding dogs with machines is impossible. [ citation needed ] The vet then goes on to say, with endless patience, that a Roomba is not a pet. This is taken by Megan as if the doctor said that her Roomba-like device is a non-domesticated animal (like a monkey, a fox, or the birds referred to in the title text) that can but should not be kept in captivity. In the last panel she consequently releases the vacuum cleaner and it whirs to its 'freedom'. The second customer, Hairy , has his dog on a leash, but is also carrying a pet transporter for the dog. Most likely he has arrived with the dog in the transporter (perhaps using public transportation) but has now taken it out so it can walk for itself, making the carrier much lighter. The Migratory Bird Treaty act from the title text contains a list of over 800 bird species that are not allowed to be captured or killed. If the Roomba were to be classified as a native American bird and were added to the list, keeping them as pets would constitute capturing and would be considered illegal. This, of course, shows how confused Megan is. She previously stated the Roomba to be a dog and now apparently believes it is a bird, even though dogs are not birds [ citation needed ] and neither is the Roomba. [ citation needed ] [Megan arrives with a pet carrier, Cueball stands at a desk as a veterinarian, and Hairy is waiting behind a rope, standing next in line with a dog on a leash and a pet carrier.] Megan: There's something wrong with my dog. He keeps crawling around eating dirt. [Cueball holds the content of Megan's pet carrier, a flat disk. She is standing behind the desk with the carrier on the desk.] Cueball: This is a Roomba. Megan: Well, he's a mix. Megan: Probably some Roomba in there. [The Roomba now lies on the table next to the carrier between the two.] Cueball: A Roomba is not a pet. Megan: You're right. It's wrong to keep a beautiful creature like this in a house. [Megan is outside left to a tree, arms up in the air, encouraging the Roomba to drive away.] Megan: Go! Megan: Be free! Roomba: Whirrr

Driving

Driving

https://www.xkcd.com/1559

https://www.explainxkcd.com/wiki/index.php/1559:_Driving

[Black Hat, carrying a rock, is walking toward Cueball, leaving a trail of sand.] Black Hat: Would you guess this weighs as much as a small adult? Cueball: What? Cueball: Uh, probably. [Black Hat walks past Cueball who turns to look after him.] Black Hat: Great! [Black Hat has walked out of the frame. Cueball is looking in the direction he left in. Several noises and voices are coming from off-panel.] Off-panel: *Thump* Car voice (off-panel): Please fasten your seatbelt. Off-panel: *click* Black Hat (off-panel): Take me to Anchorage, Alaska. Car voice (off-panel): Navigating Off-panel: *slam* [Black Hat walks back in the panel towards Cueball.] Car driving off: Vrrrrrrrrrrrr rrrr rrrrr rr Black Hat: I love self-driving cars. Cueball: ...Whose car was that? Black Hat: Dunno, but they shouldn't have left it running.

A self-driving car is a car that requires no human interaction to navigate streets to a destination. Thus, when Black Hat places a rock that weighs "as much as a small adult" into the car's seat, he begins the process of fooling the car into thinking it has an occupant when it does not. His purpose in doing so appears to be to send the car to Anchorage , Alaska , which is presumably quite far from where Black Hat and Cueball are standing, thus taking the car far away from its owner with relatively little effort on the part of Black Hat. This is yet another evil prank from xkcd's resident classhole . The title text references the fact that driving to Alaska from the contiguous lower 48 states requires two border crossings, once into Canada from the mainland, and once from Canada into Alaska. The car apparently begins some distance from the Canadian border, since it will likely run out of gas before reaching Canada. Title text expresses regret about this probable failure; perhaps Randall was looking forward to the encounter between the border guards and the vehicle's "occupant." However, even if the car does not get to Anchorage, Black Hat will have created a serious problem for its owner who will have to report the car as stolen. Shortly after this comic appeared, Tesla released footage of a robotic charger that can connect itself to a Tesla automatically. If this kind of technology becomes common then a self-driving electric car might be able to make a transcontinental journey without human intervention. At the time of the release of this comic there were no places where self-driving cars were for sale to individuals. However, several corporate-owned test cars are frequently seen on public roads (such as those operated by Google among others). Nevada, Florida, California and Michigan were the first states to allow the testing of self-driving cars on public roads, and this legality is quickly spreading to many other states, as well as several countries in Europe. Alternatively, Randall might be setting this comic in an idyllic near future, wherein you could drive all over the country (and Canada) with these cars! It could have been Beret Guy's car - see 1493: Meeting . Self-driving cars are a recurring topic on xkcd. [Black Hat, carrying a rock, is walking toward Cueball, leaving a trail of sand.] Black Hat: Would you guess this weighs as much as a small adult? Cueball: What? Cueball: Uh, probably. [Black Hat walks past Cueball who turns to look after him.] Black Hat: Great! [Black Hat has walked out of the frame. Cueball is looking in the direction he left in. Several noises and voices are coming from off-panel.] Off-panel: *Thump* Car voice (off-panel): Please fasten your seatbelt. Off-panel: *click* Black Hat (off-panel): Take me to Anchorage, Alaska. Car voice (off-panel): Navigating Off-panel: *slam* [Black Hat walks back in the panel towards Cueball.] Car driving off: Vrrrrrrrrrrrr rrrr rrrrr rr Black Hat: I love self-driving cars. Cueball: ...Whose car was that? Black Hat: Dunno, but they shouldn't have left it running.

Bubblegum

Bubblegum

https://www.xkcd.com/1560

https://www.explainxkcd.com/wiki/index.php/1560:_Bubblegum

[Beret Guy stands dramatically silhouetted in a doorway.] Beret Guy: I came here to chew bubblegum and make friends! [Beret Guy, in normal lighting, looks at Megan and Cueball who stare back. A silent beat panel.] [Beret Guy put his hand out offering a stick of gum to Megan and Cueball.] Beret Guy: Want some gum?

This comic spoofs the iconic quote from the 1988 action movie They Live , where the armed protagonist, upon entering a bank, states that "I have come here to chew bubblegum and kick ass, and I'm all out of bubblegum." This implies that the protagonist will soon fight the people in the bank, as he cannot do the other objective he came there for (chewing bubble gum). This phrase was also used by the title character of the video game Duke Nukem 3D and is often mistakenly believed to have originated in it. Furthermore, the phrase has itself been parodied by British comedy IT Crowd , and by Mystery Science Theater 3000 in the episode 521 "Santa Claus" ("Ho-ho-ho! I'm here to kick butt and lick candy canes, and I'm all out of candy canes!"), and a version appeared in the 1993 movie Dazed and Confused , where Clint says, "I only came here to do two things, kick some ass and drink some beer. ... Looks like we're almost outta beer." (Note that this movie was filmed in 1993 but set in 1976, and so the character in the movie wouldn't have known about the movie They Live .) Former wrestler Rowdy Roddy Piper , who played the protagonist in They Live , died five days prior to the publication of this comic so this comic is most likely a tribute to him. The iconic quote was an ad-lib Piper himself came up with. In the comic, Beret Guy stands in an open doorway with a strong light behind him, a typical pose in action movies when someone is dramatically entering a room. However, in this instance, Beret Guy claims that he is here to "chew bubble gum and make friends". He then offers a stick of gum to both Megan and Cueball , making it clear he intends to do both of his stated objectives. This is expected from Beret Guy, who is usually both naïve about the world and beings that surround him, and also friendly to them. The title text seems to be a slight dig at the trope of a laconic hero who utters only a few gnomic words, as in the They Live scene. It is another variation of the line, with meta-humor. The speaker states that he is here to say 18 words and chew bubble gum, but reaches 18 words before he is able to finish his sentence. Thus, readers are left in ambiguity as to whether or not he is also out of bubble gum, as the line could end "and I'm all out of words", "and I'm all out of gum", or "and I'm all out of both." Of course if it is a tribute to Rowdy it could have been "and I'm all out of time!" And his time was up just then before that last word. Strangely, though, Randall has not preserved the number of words in the original film quote: there are 16. There would be 18 if 'bubble gum' (which occurs twice) were taken as two words, but in the comic, it is clear that Randall takes it as one. Beret Guy has previously indicated he has a finite number of words he can say in 1493: Meeting . In 1110: Click and Drag Megan, walking out on to a platform on the left side of the tower Burj Khalifa, says "I came here to chew bubblegum... And I'm all out of bubblegum" to which Cueball walking with her replies "That's a shame" (see picture here .) [Beret Guy stands dramatically silhouetted in a doorway.] Beret Guy: I came here to chew bubblegum and make friends! [Beret Guy, in normal lighting, looks at Megan and Cueball who stare back. A silent beat panel.] [Beret Guy put his hand out offering a stick of gum to Megan and Cueball.] Beret Guy: Want some gum?

Water Phase Diagram

Water Phase Diagram

https://www.xkcd.com/1561

https://www.explainxkcd.com/wiki/index.php/1561:_Water_Phase_Diagram

[A phase diagram is shown with eight labeled regions.] [The horizontal axis, increasing in value to the right is labeled:] Temperature [The vertical axis, increasing in value downwards is labeled:] Pressure [Region alongside the "Pressure" axis covering about half of its length is labeled:] Ice [Region spanning top-right corner of graph, i.e. higher temperatures and lower pressures. The region is labeled:] Water vapor [Region below "Water vapor" and to the right of "Ice" is labeled:] Liquid water [Three small regions below "Ice" are going from left to right on the same pressure region, the last ending just under "Liquid water". They are each labeled:] Ice II Ice III Ice V [Region below "Ice II", "Ice III", "Ice V" and "Liquid water" is labeled:] Vanilla Ice (Ice VI) [Below "Vanilla Ice" there is a dashed line with two arrows pointing downwards. The region below the dashed line is labeled:] David Bowie & Queen

This is a modified version of the phase diagram for water . A "phase diagram" is a chart that shows the states, or "phases", that a substance will be in under various temperatures and pressures. Water's phases are particularly well-studied; on the real phase diagram for water , there are a great many phases listed. Most people are familiar with three phases of water — solid ( ice ), liquid (water), and gas ( vapour ) — and with the fact that an increase in temperature will cause water to change from one state to another. The gas and liquid phases are quite straightforward; however, there is in fact not one single solid phase of water, but a variety of numbered phases ("ice I" through "ice XVI" are currently recognized), several of which are divided into sub-categories. Ordinary, everyday ice is known as " ice I h " ("ice one-h"). Most of the more unusual forms of ice only form under very high pressure . Randall's phase diagram starts out realistically, though slightly simplified in several ways. For one, it simply uses the name "ice" for the usual form(s). It is focused in on a narrower area than the more complete diagram linked earlier; on that version, the "ice V" region is quite small, and "ice III" is barely visible, whereas both are quite plain to see on Randall's diagram. Lastly, where most phase diagrams have pressure increase upwards, Randall has the pressure scale increase downwards, this has been chosen to make it possible for the jokes to appear at the bottom of the chart. Else the comic would not be funny for the average reader. Because, as the diagram continues downwards and the pressure increases, the jokes begin. Beyond the moderately high-pressure forms of ice (ice II, III and V), a real phase diagram has ice VI; Randall has "Vanilla Ice (ice VI)". Vanilla Ice is the stage name of a white rap/hip-hop artist from the 1990s; the initials of Vanilla Ice, and the Roman numeral six, are both VI. Vanilla Ice's biggest hit, " Ice Ice Baby ", used samples from the earlier song " Under Pressure ", by David Bowie and Queen ; accordingly, on Randall's diagram, the "Vanilla Ice" region transitions to "David Bowie & Queen" when it is under (even higher) pressure. Further references to "Ice Ice Baby" are found in the title text. Near the beginning of the song, Vanilla Ice raps the line, "All right stop, collaborate and listen". The unusual choice of "collaborate" in this line has made it memorable, and the word is used in the title text (in a more typical context). The phrase "survive at room temperature for several months" is likely a reference to "Ice Ice Baby" being Vanilla Ice's only major hit, humorously suggesting he faded out of the public view after a few months of fame. Finally, even the word "sample" may be deliberately chosen as a reference to the sampling of "Under Pressure". "Ice Ice Baby" was written in 1983, but in 1990 Vanilla Ice finally admitted that he used unmodified samples from "Under Pressure" and paid royalties to Queen and Bowie. When originally published, another image was faintly visible just below and to the right of the "Water vapor" label. It appeared to be a copy of an actual phase diagram for water from Wikipedia . The image has since been removed, lending support to speculation that it was an error (perhaps an image Randall referred to in drawing the comic, but accidentally left in the final result). Alternatively, it may have been deliberate—suggestions include its presence being a water mark, or a reference to the "Full text of the Wikipedia article on pareidolia" joke in the 1551: Pluto comic. Randall has referenced "Ice Ice Baby" and "Under Pressure", separately and together, on many previous occasions, notably in 159: Boombox and 210: 90's Flowchart . The gag of having the performers of "Under Pressure" also being literally under pressure was also used in 1040: Lakes and Oceans . The what if? that was current at the time of this comic's publication was 138: Jupiter Submarine , which began with an even more fanciful phase diagram: that of a submarine. It also contains a reference to the songs "Under Pressure" and "Ice Ice Baby" in one figure, and "Can't Touch This" by M.C. Hammer in the title text of that figure (which generated similar controversy for sampling "Superfreak" by Rick James). The title text of 1434: Where Do Birds Go whimsically suggests another possible phase of water/ice. As mentioned above, the small image on the original version could be a reference to the "Full text of the Wikipedia article on pareidolia" joke in the 1551: Pluto comic. [A phase diagram is shown with eight labeled regions.] [The horizontal axis, increasing in value to the right is labeled:] Temperature [The vertical axis, increasing in value downwards is labeled:] Pressure [Region alongside the "Pressure" axis covering about half of its length is labeled:] Ice [Region spanning top-right corner of graph, i.e. higher temperatures and lower pressures. The region is labeled:] Water vapor [Region below "Water vapor" and to the right of "Ice" is labeled:] Liquid water [Three small regions below "Ice" are going from left to right on the same pressure region, the last ending just under "Liquid water". They are each labeled:] Ice II Ice III Ice V [Region below "Ice II", "Ice III", "Ice V" and "Liquid water" is labeled:] Vanilla Ice (Ice VI) [Below "Vanilla Ice" there is a dashed line with two arrows pointing downwards. The region below the dashed line is labeled:] David Bowie & Queen

I in Team

I in Team

https://www.xkcd.com/1562

https://www.explainxkcd.com/wiki/index.php/1562:_I_in_Team

[Hairy and Cueball stand opposite each other.] Hairy: Remember, there's no "I" in "team". Cueball: No, but there's a "U" in "People who apparently don't understand the relationship between orthography and meaning".

"There's no I in team" is a well-known saying that tries to encourage teamwork by reducing each member's individual self-importance. The intention of the phrase is to remind team members that, just as the letter "i" is not present in the word "team", focus on the metaphorical "I" (i.e. individual self-interest) is not constructive in teamwork. It can be used as a light reprimand to a team member who isn't cooperating, with the reminder that when working as a team one cannot think only for oneself, and must work in partnership with the rest of the team towards a common goal. The phrase "no I in team" dates from the 1960s in the USA with printed references [1] showing it is familiar to baseball pitchers such as Vern Law . As an aside, it's interesting that it seems to come from baseball, a sport where players have significantly more independence compared to, say, rugby . Interestingly, the letters M and E can both be found in "team." This suggests that the phrase "There's no I in team" was a slight victim of cherry picking . This comic makes fun of this, and uses an extreme example, by Cueball taking the sentence literally, as a metalingual comment (see Jakobson's functions of language ), and he points out to Hairy that the spelling (or orthography ) of a word doesn't relate to its meaning (an instance of the use–mention distinction ). Cueball is using the same joke against Hairy by saying there is a "u" in "People who apparently don't understand the relationship between orthography and meaning". There is a "u" (pronounced as "you") in what Cueball said, implying that Hairy is included in the set of people who mistakenly link orthography and meaning. Of course, it's very likely that Hairy knows that orthography doesn't determine meaning, and could easily reply "There's also a 'u' in 'People who take aphorisms too literally' ". On the other hand, there is in fact no 'u' in that sentence, which would make it the one actually false statement mentioned. The title text "There's no 'I' in 'VOWELS'." provides another illustration of the distinction between orthography and meaning. "A", "I" and "U" are vowels, notwithstanding the irrelevant fact that they are not included in the spelling of "VOWELS". Orthography was the subject of 1069: Alphabet . [Hairy and Cueball stand opposite each other.] Hairy: Remember, there's no "I" in "team". Cueball: No, but there's a "U" in "People who apparently don't understand the relationship between orthography and meaning".

Synonym Movies

Synonym Movies

https://www.xkcd.com/1563

https://www.explainxkcd.com/wiki/index.php/1563:_Synonym_Movies

[Ten DVDs on a shelf. The first three stand together to the left, the two to the right leaning on the first. The next three are standing straight in the middle and then the next four are standing straight to the right. The movie titles are written on the back of the DVD cases, in white on the gray DVD cases. The text is written, so it is supposed to be read when the DVD is lying down.] Space Fights: Sudden Optimism Space Fights: The Government Wins This One Space Fights: The Sword Wizard Is Back The Jewelry God: The Jewelry Team The Jewelry God: Double Houses The Jewelry God: We Have a Czar Again Space Trip: The Movie Space Trip: That Guy is Angry Space Trip: Where is the Vulcan Space Trip: Let's Go Back [Caption below the frame:] Synonym Movies

This comic shows several "Synonym Movies". It takes several well known movies, but changes each word of their names into a synonym. So Star Wars has turned into Space Fights , The Lord of the Rings into The Jewelry God and Star Trek into Space Trip . All these movies series have the same heading, and then a subtitle. There are ten of them in the comic, and two more in the title text. This comic became a series when more movies were spoofed in 1568: Synonym Movies 2 . The use of synonyms makes all these movies look ridiculous, for example, "The Sword Wizard Is Back" is a laughable sounding movie [ citation needed ] , whereas " Return of the Jedi " sound perfectly reasonable to us. Randall may be poking fun at movies that have ridiculous titles already, for instance some people think this applies to a title like " Terminator: Genisys ". The title text refers to the latest Star Wars movie (2015-12-18), after Disney acquired the movie rights. The movie is called Star Wars: The Force Awakens and has now turned into Power Gets Up . As usual, with any Star Wars related material, there is a huge fan base that eagerly awaits the new movie. But then again many people fear that it will not live up to their expectations, as was the case with the fourth movie, first of the three movies in the second installment of Star Wars, Star Wars: The Phantom Menace , dubbed here as The Scary Ghost . As mentioned in the title text, that movie did not live up to the hype. A similarly humorous effect is achieved in 1133: Up Goer Five which explains the Saturn V rocket, but words and phrases are replaced with synonyms which are chosen from the most common English words. This renders ordinary words like "rocket" into "flying space car", or "helium" into "funny voice air" for example. SPOILER ALERT! Many of these explanations contain information revealed during the movie. [Ten DVDs on a shelf. The first three stand together to the left, the two to the right leaning on the first. The next three are standing straight in the middle and then the next four are standing straight to the right. The movie titles are written on the back of the DVD cases, in white on the gray DVD cases. The text is written, so it is supposed to be read when the DVD is lying down.] Space Fights: Sudden Optimism Space Fights: The Government Wins This One Space Fights: The Sword Wizard Is Back The Jewelry God: The Jewelry Team The Jewelry God: Double Houses The Jewelry God: We Have a Czar Again Space Trip: The Movie Space Trip: That Guy is Angry Space Trip: Where is the Vulcan Space Trip: Let's Go Back [Caption below the frame:] Synonym Movies

Every Seven Seconds

Every Seven Seconds

https://www.xkcd.com/1564

https://www.explainxkcd.com/wiki/index.php/1564:_Every_Seven_Seconds

[Cueball is walking with four thought bubbles above him.] Cueball (thinking): There’s no way that’s true. It would interfere with basic cognition. Such a ridiculous view of masculinity. How would you even study that? [Caption below the panel:] Every seven seconds, sociologists think about that made-up statistic about how often men think about sex.

There is an oft-stated urban myth that men think about sex every seven seconds. See for example this BBC article , where they say that a more realistic number is 19 times in a waking day, i.e. once every 50 minutes. In this comic Cueball is a sociologist , and the thought bubbles show his train of thoughts regarding this myth. First of all, he flatly denies that it could be true, and progressively his thoughts move to the effects if it were true, and then Cueball considers how it would even be studied. The title of the comic (Every seven seconds) hints strongly that this is the subject he is thinking about, and this is subsequently confirmed both in the caption and in the title text. The setup is that thinking about sex every seven seconds would be dysfunctional and unproductive in addition to making working, social interactions and etcetera nearly impossible as explained by the sociologist's thoughts. The punch line is that thinking every seven seconds about how ridiculous it is to think about sex every seven seconds is just as dysfunctional and unproductive even if the thought time is spent refuting the original notion as understood in third person. The irony of the comic is that in thinking every seven seconds about how impossible it would be for men to think about sex every seven seconds, the sociologist is, in fact, thinking about sex every seven seconds, albeit in a roundabout way. In the title text, the narrator ( Randall or Cueball the sociologist?) says he thinks about how implausible it would be to have sex every seven seconds, several times a year. See alternate interpretations below: In the title text, the narrator's statement leaves some meaning up to interpretation: [Cueball is walking with four thought bubbles above him.] Cueball (thinking): There’s no way that’s true. It would interfere with basic cognition. Such a ridiculous view of masculinity. How would you even study that? [Caption below the panel:] Every seven seconds, sociologists think about that made-up statistic about how often men think about sex.

Back Seat

Back Seat

https://www.xkcd.com/1565

https://www.explainxkcd.com/wiki/index.php/1565:_Back_Seat

[Caption above the panel.] Protip: [Cueball is holding the back door of his car open. Wiggly lines emanate from the back seat area. Megan and another Cueball-like guy are stand next to the car, looking at each other.] Cueball: Hang on, I just have to clear a few things out of the back.: [Caption below the panel.] When you hear "I just have to clear a few things out of the back," you are about to see, at minimum, a decaying raccoon.

This comic makes fun of the common situation of a messy car, using a hyperbolic scenario of that car containing decaying animals, in this case a raccoon . The joke being that such a car is so disgusting that a dead raccoon is not the worst thing that one might encounter. The humor comes from the car owner seeming to be used to a dead raccoon and the implications of what might be worse than a dead raccoon. This is the polar opposite of 1267: Mess , where the person apologizes for a nearly non-existent mess. Here, the person minimizes a completely atrocious mess into a quick fix situation. The form of the comic is that of a pro-tip, which tells the reader what the phrase "I just have to clear a few things out of the back" really means. ' Protips ' are used to give snarky, obvious or inadequate advice, in order to either humor a well-learnt audience or to prank a naïve audience. This phenomenon originated in a gaming magazine column offering advice on Doom : "To defeat the Cyberdemon, shoot at it until it dies. [ citation needed ] ", or "fire is hot [ citation needed ] " Randall has given us several Protips in the past as well. The title text further exposes the reality of the person's knowledge of how bad the situation really is when he acknowledges the existence of the dead raccoon while trying to usher the live one to the same side. Protip: Sitting next to a dead and a live raccoon is not an improved scenario, as the dead raccoon would probably be decaying, leaking bodily fluids into the back seat, staining the seat and making it wet, while the live raccoon may be aggravated, and possibly attacking the occupants of the vehicle. [Caption above the panel.] Protip: [Cueball is holding the back door of his car open. Wiggly lines emanate from the back seat area. Megan and another Cueball-like guy are stand next to the car, looking at each other.] Cueball: Hang on, I just have to clear a few things out of the back.: [Caption below the panel.] When you hear "I just have to clear a few things out of the back," you are about to see, at minimum, a decaying raccoon.

Board Game

Board Game

https://www.xkcd.com/1566

https://www.explainxkcd.com/wiki/index.php/1566:_Board_Game

[Hairy, Cueball, Ponytail (reading something), and Hairbun (holding some cards) are sitting around a table. There are several other objects on the table.] Cueball: ...Now, this pile is "allowable deduction" cards. You match them with cards in your hand to preserve their full point value. Cueball: Over here are "dependent" tokens... [Caption below the frame:] Every year, I trick a local board game club into doing my taxes.

In this comic, Cueball is shown explaining the rules of a board game to three other players ( Hairy , Ponytail , and Hairbun ) of a local board game club – a hobbyist group that gets together to play board games. However, the board game Cueball is explaining is actually his own creation which is designed to trick the club into preparing his income tax return. The caption indicates that Cueball does this every year, which makes this comic reminiscent of the My Hobby series. An income tax return is an annual document which most adults (and some teenagers) in many countries must prepare and submit to the government agency responsible for tax collection. The document sets out that person's income for the year, along with offsets including deductions and credits, and calculates the amount of income tax the person is required to pay to the government (used by the revenue service to compare it to the value that person had actually paid). The return requires understanding of a number of forms which may seem complicated to those not familiar with them. It is an annual task that is stereotypically met with confusion and disdain. Many people hire professionals to prepare their taxes. More recently, software-based solutions that walk the user through a series of more understandable text-based questions are available to aid taxpayers in completing their returns; however these are not always ideal for those with complicated returns. In this comic, Cueball has developed his alternative method of tax preparation which utilizes the collective intelligence of several board-game-club players, and also capitalizes on the fact that members of such a club are likely very competitive and eager to succeed at board games. As a result (as the title text suggests), Cueball thinks the board game players are more thorough than the tax preparation professionals he has previously used. Such professionals would prepare perhaps hundreds of returns per year and as a result, might indeed be less thorough with each individual return which may all be viewed as fairly simple and repetitive by the professional. Among the rules Cueball explains are references to "allowable deduction" cards which presumably reference certain deductions which are allowed on income tax returns to lower the net income (resulting in lower taxes). For example; a portion of certain medical expenses are permitted to lower one's income in recognition of the fact that using one's income for medical expenses is somewhat non-discretionary. Similarly, certain charitable donations are permitted as deductions to encourage such donations. In Cueball's game, players must match the deductions with other cards to preserve their full "point value". This appears to be a reference to the desire to capitalize as much as possible on the value of a deduction by taking the deduction against income which would otherwise incur the greatest tax, and ensuring that the full amount of the deduction can be used. A deduction of $2,000 against income of $1,000 would waste half the deduction. In gaming, tokens are small playing pieces which may represent various things, depending on the game. In many board games (e.g. Monopoly ), tokens represent the players themselves. In other games, such as Magic: The Gathering , tokens can represent creatures or other items in a player's inventory. Cueball references "dependent tokens" which appear to be game tokens representing Cueball's dependents. Dependents are individuals for whom the taxpayer is entitled to certain deductions and credits, often related to expenses incurred to care for the dependents. Most commonly, dependents are the minor children whom the taxpayer is required to support financially, but in the United States (where Randall lives) a person can claim a qualifying child as a dependent as long as the qualifying child lives with the claimant and is not self-supporting, even if the claimant is not the person who supports the qualifying child, and a person who voluntarily supports another (without being required) may also qualify to claim the person. Also, U.S. law usually does not allow a person's own spouse to be claimed as a "dependent", even when financial support is required. Note that while Cueball states he "tricks" his board game club into doing his taxes, in fact his use of clear tax terms ("allowable deductions", "dependent") for naming different tokens and elements of the game could suggest that the players knew what he was doing but going along with it because they just enjoy playing board games, such that even doing a tax return – often considered a boring mind-numbing chore – within the format of a board game would be something they would enjoy doing. (On the other hand, it's possible that the players don't realize that the game involves preparing Cueball's own tax return.) Alternatively, the comic may be comparing the tediousness of some board games to that of doing tax returns. It is noted that there are board games on a variety of unexpected topics which might seem like boring subjects for a game. For example, there are several games designed to simulate the stock market and investing. The popular video game Farmville is often joked about having created a successful game out of a job most people would find unpleasurable. This suggests it might actually be possible to create an board game enjoyable to some people from the process of preparing a tax return. This is one of several xkcd comics that suggest going to comically extreme lengths to avoid doing something (in this case, his taxes) that might have been simpler to do normally than the way Randall proposes. In this case, Cueball suggests that his motives may actually be to get the most thorough preparation possible, rather than to simply find a way to get the task done. There is actually a pretty solid basis to for this. Both gamification and crowdsourcing have been shown, in at least some cases, to produce results that can match or exceed those produced by professionals. For example, the University of Washington created an online game in which users tried to optimize the folding of protein structures. The results produced by players produced useful new structures more quickly than computer simulations were able to. In this case, the work is being done by people who presumably have at least some enthusiasm for games, and who are likely competing with one another for the best results. Randall can then use the best outcome (that created by the winner) to optimize his own tax return. A similar situation of Randall secretly exploiting someone's interest for his own purposes occurs in 1323: Protocol . And another board game can be found at 492: Scrabble . This was the first time Randall made a comic about people having trouble understanding the US tax system. Since then he has two years in a row made comics in relation to an approaching tax day. See the title text of 1805: Unpublished Discoveries and the entire comic 1971: Personal Data . [Hairy, Cueball, Ponytail (reading something), and Hairbun (holding some cards) are sitting around a table. There are several other objects on the table.] Cueball: ...Now, this pile is "allowable deduction" cards. You match them with cards in your hand to preserve their full point value. Cueball: Over here are "dependent" tokens... [Caption below the frame:] Every year, I trick a local board game club into doing my taxes.

Kitchen Tips

Kitchen Tips

https://www.xkcd.com/1567

https://www.explainxkcd.com/wiki/index.php/1567:_Kitchen_Tips

[Cueball at a kitchen counter, with various items, holding a meat thermometer.] Cueball: If you're anything like me, you may have trouble telling when meat is fully cooked. Cueball: Instead of guessing, try a meat thermometer! [Cueball at a sink, holding a dirty dish, with a trashcan next to him full of broken ceramics and glasses.] Cueball: If you're anything like me, you probably throw away your plates and glasses when they get dirty. But if you clean them, they can often be used again! [Cueball cracking an egg over a pan on a hot stove.] Cueball: Making scrambled eggs? Put a pan under them! Cueball: It's easier, and it keeps your burners clean. [Cueball holding a garden hose, spraying it into the freezer compartment of a freezer.] Cueball: If you're anything like me, you make ice by spraying a hose into your freezer and then slamming it shut. Cueball: But there's a better way...

This is another one of Randall's Tips , this time with a series of Kitchen tips. In this comic, Cueball appears to be hosting a show (or be in an ad) giving out kitchen advice. He starts with a reasonable tip to use a meat thermometer instead of guessing when meat is cooked. His later tips, though, are little more than telling how to complete normal kitchen activities performed using common sense. Moreover, in most cases he repeats "If you're anything like me," suggesting he's actually done these things in his kitchen. This is a parody of many commercials and infomercials that imply their consumers have no basic motor skills or common sense in order to make their product more appealing. The first tip he gives is reasonable because, though the use of a meat thermometer is fairly well known, not everybody goes to the trouble of using one. To determine if meat is done cooking, one can either guess or use a meat thermometer to check that the internal temperature has reached the correct level to render meat safe for consumption. Many people don't own a meat thermometer and rely on an alternative solution that doesn't require special equipment (such as testing by feel, cutting the meat open to check its doneness, checking the color of the juices after pricking the meat with skewer, or simply guessing). The second panel shows that Cueball throws away dishes and buys new ones every time they are used. This is perfectly normal if the plates are disposable plates made of paper or Styrofoam (though not exactly environmentally friendly), but we see his trashcan is filled with chipped glasses and ceramic plates. Naturally, this would be a very expensive practice. The virtually universal chore of "washing the dishes," is one Cueball presumes the audience is heretofore unaware of. Cooking on a stove is typically done placing the food into a pot or pan which is placed on the burner [ citation needed ] . Cueball seems to suggest that the use of a pan is a tip most people would be unaware of, suggesting that most people cook eggs directly on the burners themselves, a method that is likely to burn the food and create a great mess. Cueball's stove has T-shape raised burners (probably gas, but might be electric), making the task very impractical, though owners of glass-top electric stoves could conceivably cook directly on the glass surface. Ice is usually made by filling an ice cube tray with water and leaving it in a freezer for several hours. Cueball, however, sprays a hose directly into his freezer compartment and quickly slams the door shut to trap some water inside. (This would work somewhat better in a chest freezer, which has a door on the top, as it could be filled with water and the door would not need to be closed to trap the water inside.) While this unorthodox method will make ice, it will result in a large sheet of ice on the bottom of the freezer. More importantly, it will also make it impossible to actually use the freezer to hold anything else (unless you were to put anything in beforehand and you don't mind breaking through a block of ice to get it out). Also, ice expands as it cools (it is one of the few substances with a negative coefficient of thermal expansion), and its expansion might push the freezer door open. The title text, a household tip , suggests using toilet paper a few sheets at a time, which is how most people use it. Cueball, however, seems to suggest that most people use the entire roll as a single object without unspooling it and then flushing it whole, using at least one roll each time they use the bathroom. This is economically impractical, and is prone to clogging the toilet and the plumbing if you throw the toilet paper away by putting it into the toilet and flush it. For more household tips like the one in the title text, see the sequel to this comic: 1715: Household Tips . [Cueball at a kitchen counter, with various items, holding a meat thermometer.] Cueball: If you're anything like me, you may have trouble telling when meat is fully cooked. Cueball: Instead of guessing, try a meat thermometer! [Cueball at a sink, holding a dirty dish, with a trashcan next to him full of broken ceramics and glasses.] Cueball: If you're anything like me, you probably throw away your plates and glasses when they get dirty. But if you clean them, they can often be used again! [Cueball cracking an egg over a pan on a hot stove.] Cueball: Making scrambled eggs? Put a pan under them! Cueball: It's easier, and it keeps your burners clean. [Cueball holding a garden hose, spraying it into the freezer compartment of a freezer.] Cueball: If you're anything like me, you make ice by spraying a hose into your freezer and then slamming it shut. Cueball: But there's a better way...

Synonym Movies 2

Synonym Movies 2

https://www.xkcd.com/1568

https://www.explainxkcd.com/wiki/index.php/1568:_Synonym_Movies_2

[22 DVDs on a shelf in four groups. All DVDs are labeled in black on light grey. Text written so it is supposed to be read when the DVD is lying down.] [First group of 8 DVDs. All standing straight.] Wandboy and the Magic Rock Wandboy and the Hidden Room Wandboy and the Fugitive Wandboy and the Burning Cup Wandboy and the Firebird Club Wandboy and the Book Owner Wandboy and the Magic Stuff (1/2) Wandboy and the Magic Stuff (2/2) [Second group of six DVDs. Five standing straight, last on the right leaning against the rest.] Puncher Puncher II Puncher III Puncher IV Puncher V Puncher Lastname [Third group of four DVDs. First and last standing straight, others leaning on first.] Tropical Boaters: Spooky Boat Tropical Boaters: Angry Wormface Tropical Boaters: Boats Everywhere Tropical Boaters: Vitamin Water [Fourth group of four DVDs. Three standing straight, second from left leaning on first.] Professor Whip and the Box of God Professor Whip and the Scary Church Professor Whip Looks for a Cup Professor Whip is in Another Movie

This comic made a series out of its predecessor as it continued the idea from 1563: Synonym Movies with a new set of movie series. As with the previous comic, the titles aren't always direct synonyms with the original (Indiana Jones as Professor Whip ), but now it seems to be even more exaggerated, sometimes making synonyms of the plot synopsis instead of the subtitle ("Vitamin Water" refers to the Fountain of Youth rather than the Stranger Tides ). This set includes Wandboy ( Harry Potter ), Puncher ( Rocky ), Tropical Boaters ( Pirates of the Caribbean ), and Professor Whip ( Indiana Jones ). The is in Another Movie title in the Professor Whip series differs from the other titles in that it does not reference the plot of the movie. The more dismissive reference may be due to Indiana Jones and the Kingdom of the Crystal Skull being poorly received by fans of the series. The title text is a reference to the TV series Game of Thrones , based on the book series A Song of Ice and Fire . All of these titles are direct synonyms, but such that they remove most of the meaning from the titles. For instance, nobody actually cares about the physical object of a throne, but the political power it represents. Birds eating in general have a very different implied meaning than crows feasting specifically, as groups of crows only gather to eat when there is a lot of food, such as a corpse, and as such have a strong cultural association with death and slaughter. SPOILER ALERT! Many of these explanations contain information revealed during the movie. [22 DVDs on a shelf in four groups. All DVDs are labeled in black on light grey. Text written so it is supposed to be read when the DVD is lying down.] [First group of 8 DVDs. All standing straight.] Wandboy and the Magic Rock Wandboy and the Hidden Room Wandboy and the Fugitive Wandboy and the Burning Cup Wandboy and the Firebird Club Wandboy and the Book Owner Wandboy and the Magic Stuff (1/2) Wandboy and the Magic Stuff (2/2) [Second group of six DVDs. Five standing straight, last on the right leaning against the rest.] Puncher Puncher II Puncher III Puncher IV Puncher V Puncher Lastname [Third group of four DVDs. First and last standing straight, others leaning on first.] Tropical Boaters: Spooky Boat Tropical Boaters: Angry Wormface Tropical Boaters: Boats Everywhere Tropical Boaters: Vitamin Water [Fourth group of four DVDs. Three standing straight, second from left leaning on first.] Professor Whip and the Box of God Professor Whip and the Scary Church Professor Whip Looks for a Cup Professor Whip is in Another Movie

Magic Tree

Magic Tree

https://www.xkcd.com/1569

https://www.explainxkcd.com/wiki/index.php/1569:_Magic_Tree

[Beret Guy and Megan stand next to a large pole with a note on it. Beret Guy points at the pole.] Beret Guy: Check it out! I threw my magic beans on the ground here yesterday, and this big tree appeared! [Zoom out, the pole is revealed to have branches. Around the pole are trees about 1/9th of the height of the pole.] Megan: That's a cell tower. Beret Guy: No way - it has branches! Beret Guy: See? Beret Guy: I'm gonna climb it! [Same as frame as the first. Beret Guy starts climbing the pole.] Megan: No, they just put those there to make it look- Megan: ...Never mind. [There is a caption in a small frame inlaid at the top of the last frame:] Later... [Megan looks at her phone while Beret Guy walks towards her holding an axe.] Megan: Why do I have no signal? Beret Guy: There were scary giants with yellow helmets in that tree! Luckily I cut it down before they ate me.

This comic features a running theme in the xkcd comics, Beret Guy 's naive and/or odd ways of thinking. In the beginning of the comic, Beret Guy shows Megan what he believes to be a tree, and explains that it grew there because he placed magic beans in that spot yesterday. This is a reference to the fable " Jack and the Beanstalk ", where the protagonist plants several magical beans he acquired, resulting in a beanstalk growing which ascends into the atmosphere. Megan, however, tells Beret Guy that the "tree" is actually a cell phone tower . Beret Guy disagrees, pointing out that it has branches, to which Megan tries to explain that this was in an attempt to make the towers look like trees . She gives up, however, as Beret Guy has already begun climbing the tower, or because she fears that giving this explanation would only add fuel to the fire that is Beret Guy's imagination. Later, Megan complains that her cell reception has disappeared. Beret Guy responds by saying that he had to cut down his "tree" because there were "scary giants with yellow helmets" in it (presumably, construction workers). This mirrors, again, the "Jack and the Beanstalk" fable, where the protagonist has to cut down his beanstalk to prevent the giant, whose lands the beanstalk connects to, from climbing down and chasing him. In reality, the "giants" were probably utility workers. The title text suggests that, over time, trees will evolve to start looking more like cell phone towers in a form of mimicry in order to avoid people cutting them down. Mimicry is where a creature copies the appearance or behavior of another in order to confuse predators. In this scenario, the more defenseless trees attempt to mimic cell phone towers, which have the defense of people not wanting to cut them down or they would lose cell service (and likely a significant amount of money through fines) and because of society's general respect for the property of others, as well as the dangers of electrocution or radiation. This is similar to the counting pine , a tree in Terry Pratchett's Discworld series that evolved to display its age with numbers on the outside (in the bark) in the hope that humans would not cut it down and count its rings. Of course now humans hunted it down trying to find a tree with numbers that would fit their house number instead, thus quickly rendering the trees almost completely extinct. (See the tribute to Terry in 1498: Terry Pratchett ). Convergent evolution deals with multiple species acquiring similar characteristics to fulfill their role (such as dolphins and sharks both having a streamlined shape to swim fast) due to the species' common need to adapt to similar environments or tasks. Randall uses the term to describe the convergence in the appearances of cell towers whose design has "evolved" to include tree-like branches and trees which he predicts will evolve to resemble cell phone towers. Each of these "evolutions" would be for the purposes of camouflage, although the cell towers "evolve" by human design for purely aesthetic reasons and the trees would evolve naturally for self-preservation. This would therefore not be a true example of convergent evolution. It more closely resembles Batesian mimicry, or the evolutionary process by which a species remains noticeable, but treated as something it is not. [Beret Guy and Megan stand next to a large pole with a note on it. Beret Guy points at the pole.] Beret Guy: Check it out! I threw my magic beans on the ground here yesterday, and this big tree appeared! [Zoom out, the pole is revealed to have branches. Around the pole are trees about 1/9th of the height of the pole.] Megan: That's a cell tower. Beret Guy: No way - it has branches! Beret Guy: See? Beret Guy: I'm gonna climb it! [Same as frame as the first. Beret Guy starts climbing the pole.] Megan: No, they just put those there to make it look- Megan: ...Never mind. [There is a caption in a small frame inlaid at the top of the last frame:] Later... [Megan looks at her phone while Beret Guy walks towards her holding an axe.] Megan: Why do I have no signal? Beret Guy: There were scary giants with yellow helmets in that tree! Luckily I cut it down before they ate me.

Engineer Syllogism

Engineer Syllogism

https://www.xkcd.com/1570

https://www.explainxkcd.com/wiki/index.php/1570:_Engineer_Syllogism

[An white frame with text inside an underbrace and an overbrace.] An engineer syllogism [Cueball is at his desk in front of his computer, with his hands on his knees, thinking.] Cueball (thinking): 1: I am good at understanding numbers. [Cueball takes one hand to his chin, still thinking.] Cueball (thinking): 2: The stock market is made of numbers. [Cueball lifts both arms from his legs, still thinking.] Cueball (thinking): 3: Therefore I– Wow , where did all my money just go?

A syllogism is a logical argument where two or more propositions lead to a conclusion through deductive reasoning . For example, one of the best-known syllogisms is: In this comic, Cueball is an engineer who is attempting to make the following syllogism: Since most engineers are purportedly good at math, proposition 1 seems to be true. It is also loosely true that the stock market is made of numbers, but only in the sense that every system can be given a post-hoc numeric characterization; the dynamics of the stock market are primarily human-driven. In this comic Cueball thinks that his skill at math will help him beat the stock market. Little does he know that the system can be unpredictable, so he ends up losing money as the financial instrument he's invested in loses value. This is due to the financial markets being largely controlled by humans making emotional decisions and not some calculable reason or logic. Even if the propositions "I am good at understanding numbers" and "The stock market is made of numbers" were true in Cueball's interpretation, Cueball would still be wrong to conclude that "I am good at understanding the stock market": this would be a fallacy of the undistributed middle (with the first premise being more accurately stated as "I'm good at understanding things made of numbers") and a fallacy of composition (with the implicit third premise "if I'm good at understanding the components of a system, then I'm good at understanding the system"). The problem is that proposition 1 seems to say "I am good at understanding all math". However, the "all" is not present, so Cueball may not necessarily understand the math underlying the stock market. This comic is also related to the 1998 movie Pi where the main character repeats to himself several times his assumptions that the world is all numbers, and thus he, a great mathematician, should be able to predict the stock market, which is all numbers. He believes that maybe his work on patterns in pi will provide some deeper insight into the patterns in the stock market, a project that drove his mentor crazy and may in fact be making his computer self-aware. The title text talks of the scenario where it was Cueball who causes everyone involved in the financial system to lose their money. This could refer to a scenario in which Cueball figures out a way to extract large quantities of money from the stock market, causing a sudden, major decline in everybody else's wealth, or that his involvement has caused literally everyone, including his own, stock market assets to lose their value. This is possible since there is no conservation of value for the stock market. The value of a particular stock is determined by a majority that is willing to trade it at a given price. The release date of this comic makes it highly likely that it refers at least in part to the 2015 Chinese stock market crash which largely affected most other world financial markets, particularly during the week of August 24–28, during which this comic was published. Two, less likely, interpretations of the title text have been suggested: This scenario has been mentioned before, in the title text of 592: Drama . [An white frame with text inside an underbrace and an overbrace.] An engineer syllogism [Cueball is at his desk in front of his computer, with his hands on his knees, thinking.] Cueball (thinking): 1: I am good at understanding numbers. [Cueball takes one hand to his chin, still thinking.] Cueball (thinking): 2: The stock market is made of numbers. [Cueball lifts both arms from his legs, still thinking.] Cueball (thinking): 3: Therefore I– Wow , where did all my money just go?

Car Model Names

Car Model Names

https://www.xkcd.com/1571

https://www.explainxkcd.com/wiki/index.php/1571:_Car_Model_Names

Certain letters and numbers are used disproportionately often in car models compared to regular text. (see:"Rev-4 cr-x x3 G6 Maxx") Letter and number scores based on relative frequency in car model names Carlike 60 6 55 35 74 6 27 5 27 64 32 12 19 40 8 15 41 126 83 0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z English-like -74 -58 -67 -37 -14 -5 -21 -45 -44 -21 -46 -80 -27 -18 -68 -20 -90 Based on these scores, here are a few suggestions for car companies: (with average letter scores) Names to avoid Potential hits Honda 2Chainz (-0.13) Honda 3Chainz (0.57) Mitsubishi Fhqwhgads (-0.62) Subaru Andre3000 (1.30) Kia 49AndGothy (-2.96) Suzuki Sexism (1.82) Chevrolet Niceguy (-3.09) Lincoln Marxism (2.17) Oldsmobile GoodWood (-4.44) Hyundai Climax (2.48) Infinity Toothy69 (-4.51) Porsche Zizek9000 (3.06) BMW Outhouse (-4.85) Lexus 3x3Cutrix (3.22) Volkswagen Woodpony 7OH7 (-5.70) Acura PizzaJazz (3.56) Chrysler Uh Iono (-5.65) Ford SixAxle 4x4 (3.95) Nissan Doody (-5.84) Toyota Cervixxx (4.85)

In English, letters like X and Z are rarely used in the common vernacular. Marketers have found that names with these infrequently-appearing letters sell more products. Scores There are two explanations for scores. Both of them share the fact that Randall must have used a car-name database to calculate letter frequency in car models. There are 19 positive scores and 17 negative scores, which is interpreted differently in each explanation. Score(x) = Frequency_in_cars(x) - Frequency_in_English(x) This formula generates a positive number if a letter is more common in car models than in typical English (as X) which Randall then calls carlike. The formula generates a negative number if a letter's relative frequency in car models is lower than in typical English (as O) and Randall calls it English-like (more suitable for readable text). The letters F and B, with scores of 5 and -5, respectively, are about as common in English as in car models. With this nomenclature, the most English-like letter is Y because, while not the most common English letter, it is apparently extremely rare in car models. The most common letter in ordinary English is E, which is (presumably) fairly common in car models. Score(x) = Frequency_in_cars(x) It seems that Randall arbitrarily used positive and negative numbers: if a letter is very common in car models (as X) he calls it carlike. If a letter is very uncommon in car models (as O) he calls it English-like. With this nomenclature the most English-like letter is Y, but actually Y is the least carlike letter. The most common letter in ordinary English is E. Y on the other hand is just in the middle (place 13), which can't be called English-like. Algorithm for the index Randall devised an index for car models which is the score average divided by 10. Example We take 2Chainz and add the scores of its different numbers and letters: 6 +27 -44 -14 -21 -46 +83 = -9 Average is -9/7 = -1.29 and divided by 10 it's -0.129 or -0.13. Names to avoid Potential Hits Note that Randall gives the symbol × the value of 126, which means he equates it with the letter x. index(3×3Cutrix) = (+55 + score(×) +55 +27 -68 -18 +8 -21 +126)/9/10 = 3.22. This means that the score of the symbol × is 90×3.22 - 164 = 125.8 Title text As mentioned in the comic, the index for the word "climax" is 2.48. However, applying the index to the phrase "sexclimax" yields a value of 2.72, higher than that for "climax". Certain letters and numbers are used disproportionately often in car models compared to regular text. (see:"Rev-4 cr-x x3 G6 Maxx") Letter and number scores based on relative frequency in car model names Carlike 60 6 55 35 74 6 27 5 27 64 32 12 19 40 8 15 41 126 83 0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z English-like -74 -58 -67 -37 -14 -5 -21 -45 -44 -21 -46 -80 -27 -18 -68 -20 -90 Based on these scores, here are a few suggestions for car companies: (with average letter scores) Names to avoid Potential hits Honda 2Chainz (-0.13) Honda 3Chainz (0.57) Mitsubishi Fhqwhgads (-0.62) Subaru Andre3000 (1.30) Kia 49AndGothy (-2.96) Suzuki Sexism (1.82) Chevrolet Niceguy (-3.09) Lincoln Marxism (2.17) Oldsmobile GoodWood (-4.44) Hyundai Climax (2.48) Infinity Toothy69 (-4.51) Porsche Zizek9000 (3.06) BMW Outhouse (-4.85) Lexus 3x3Cutrix (3.22) Volkswagen Woodpony 7OH7 (-5.70) Acura PizzaJazz (3.56) Chrysler Uh Iono (-5.65) Ford SixAxle 4x4 (3.95) Nissan Doody (-5.84) Toyota Cervixxx (4.85)

xkcd Survey

xkcd Survey

https://www.xkcd.com/1572

https://www.explainxkcd.com/wiki/index.php/1572:_xkcd_Survey

[A simple comic with text only. The click here part is inside a black frame.] Introducing The xkcd Survey A search for weird correlations Note: This survey is anonymous, but all responses will be posted publicly so people can play with the data. Click here to take the survey Or click here, or here. The whole comic is a link, because I still haven't gotten the hang of HTML imagemaps. This strip was referenced upon the availability of preorders for How to: Absurd Scientific Advice for Common Real-World Problems . A new banner appeared at the top of the site to announce that preorders were available; at the right of the banner was a blue box labelled "Click here to preorder", followed immediately below by "Or click anywhere. I still haven't figured out HTML imagemaps."

As the comic image states, it links to a survey created with Google Forms , containing a series of questions. The questions range from mundane typical survey questions such as “Do you have any food allergies?”, to rather strange, such as “Fill this text box with random letters by randomly mashing keys on your leopard.” (See 1530: Keyboard Mash ). The stated goal of the survey is to “create an interesting and unusual data set for people to play with”. A strange data set is a ripe opportunity for a sampling of readers. It's also supposed to be “a search for weird correlations” – presumably the goal is to be able to say things like “people who have been skydiving are (more/less) likely than average to dislike cilantro”. (See also 882: Significant about finding presumably-spurious correlations between unrelated data.) If the data is ever released, this explanation will be updated, but as of April 2022, this has not happened. HTML image maps is a technique for marking up areas of an image on a web page, such that each area can be a link without the whole image being a link. Randall could have used this type of image map to make only the “Click here to take the survey” button be a link, and none of the rest of the image. But he cannot get the hang of it (or knowing his skills, does not wish to take the time to learn it). Not getting the hang of HTML image maps was also referenced on the banner for his book tour for the what if? book The title text is a joke off of Big Data , which is a name for analysis of a set of data that includes a huge amount of information. He also says "for a big planet" because the Earth is big. [ citation needed ] The survey is closed, and the questions replaced with the text: "The xkcd survey is now closed. Thank you for all your answers! Response data is being collected and will be posted soon." As of February 2022, the same caption is still there, with no indication of exactly how soon the data is intended to be posted. (Apparently, Randall crashed google forms, so the data is taking a long time to be retrieved (see this reddit thread) - much like his breaking of Wolfram Alpha ] during answering a reader's question on what if? ) A recreation of the survey can be found here on Google . The recreation's data can be found live here. It started with the following statement: This is an anonymous survey. After it's done, a database of everyone's responses will be posted. There's no specific reason for any of the questions. The goal is to create an interesting and unusual data set for people to play with. This is obviously not going to be a real random sample of people, but in the interest of getting cooler data, if you're sharing this with friends, try sending it to some people who wouldn't normally see this kind of thing! WARNING: This survey is anonymous, but your answers WILL BE MADE PUBLIC. Depending what you write, it's possible that someone may be able to identify you by looking at your responses. None of these questions should ask about anything too private, but don't write anything that you don't want people to see. If you're not comfortable answering a question, just skip it. Note: The order of the possible answers (the list of possibilities) was random, and changed every time the page is reloaded. So do not try to fix the order here below... [A simple comic with text only. The click here part is inside a black frame.] Introducing The xkcd Survey A search for weird correlations Note: This survey is anonymous, but all responses will be posted publicly so people can play with the data. Click here to take the survey Or click here, or here. The whole comic is a link, because I still haven't gotten the hang of HTML imagemaps. This strip was referenced upon the availability of preorders for How to: Absurd Scientific Advice for Common Real-World Problems . A new banner appeared at the top of the site to announce that preorders were available; at the right of the banner was a blue box labelled "Click here to preorder", followed immediately below by "Or click anywhere. I still haven't figured out HTML imagemaps."

Cyberintelligence

Cyberintelligence

https://www.xkcd.com/1573

https://www.explainxkcd.com/wiki/index.php/1573:_Cyberintelligence

[Ponytail, pointing at a chart to her left, with text and two curves on a graph, is talking to someone off-screen to the right.] Ponytail: Our overall FY2015 cyberintelligence budget was $8.1 billion- Off-screen voice: -Yet it wasn't enough to pick up on the fact that no one else has used the prefix "cyber-" for like a decade? Ponytail: Shut up.

Ponytail presents a FY2015 ( Fiscal Year for 2015) budget for cyberintelligence , but is then interrupted with a snide remark about the prefix cyber . Although it is not specified what organization the budget is for, the size of the budget ($8.1 Billion) is large enough to suggest that it must be a large government organization such as the United States Department of Defense. This comic illustrates that some organization spends obscene amounts of money on their "cyberintelligence" budget, yet all that spending appears not to have informed them that the prefix "cyber-" fell out of fashion years ago. That the prefix could annoy experts were already used in the title text of 1084: Server Problem . The prefix "cyber" is derived from " Cybernetic ," which comes from the Greek word κυβερνητικός , meaning skilled in steering or governing. Cyberintelligence could also be called cyber spying i.e. spying in the digital world, one of many "new" words with the cyber- prefix . Many were invented in the 1980s and 1990s, following the example of " cyberspace ", popularized by William Gibson in 1982. If cyberintelligence departments were given names today, they might be called Internet Intelligence, Virtual Intelligence, Data Intelligence or Online Intelligence departments. This may be due to the fact that government organizations are typically named by middle-aged or senior officials who are generally less likely to be familiar with the current trends in technology language. They are more likely to stick to the words that were used when they first learned about the technology. Such organizations, being bureaucracies, are also unlikely to change their name. The title text continues the joke by implying the organization learned about the demise of "cyber-" yet failed to process or analyze that data. It is a common problem among intelligence organizations to gather "raw information" (such as photos, or reports from spies) but be unable to make use of it because there wasn't time to process the information into intelligence by determining what it means. This is particularly true for intelligence gathered by or relating to computers, as they can generate data far faster than people can review it. It may also be a reference to the previous comic, which was a link to a survey for xkcd readers. "Cyberspace" and " cybernetics ", illustrated here , are two of the most common words with that prefix (Cyberspace 6 times as prevalent as cybernetics at their peaks). "Cyberintelligence" is shown here . Cyberspace was used 4000 times more often, although the more common spelling splitting it in two words "Cyber intelligence" was 1.35 times more used than in one word. But even combining these two versions cyberspace is still used more than 1700 times as often. [Ponytail, pointing at a chart to her left, with text and two curves on a graph, is talking to someone off-screen to the right.] Ponytail: Our overall FY2015 cyberintelligence budget was $8.1 billion- Off-screen voice: -Yet it wasn't enough to pick up on the fact that no one else has used the prefix "cyber-" for like a decade? Ponytail: Shut up.

Trouble for Science

Trouble for Science

https://www.xkcd.com/1574

https://www.explainxkcd.com/wiki/index.php/1574:_Trouble_for_Science

[Five panels, each with the top part of a scientific article, where only the title is legible. Below is the list of authors and subheading and text in unreadable wiggles.] Many Commercial Antibody-Based Immunoassays Are Unreliable Problems With the p-Value as an Indicator of Significance Overfeeding of Laboratory Rodents Compromises Animal Models Replication Study Fails to Reproduce Many Published Results Controlled Trials Show Bunsen Burners Make Things Colder

The comic highlights the fact that several well-publicized scientific critiques have recently been published that raise questions about some commonly accepted scientific methods. For scientists, these critiques serve as reminders of the dangers of overconfidence in any method, hopefully leading those who have naively accepted results to remember that any scientific conclusion is by its very nature tentative and limited by methodological reliability. However, popular press reporting of these papers may lead a general public of modest scientific literacy to the impression that science might be in trouble, as implied by the title. Some of these methodological issues and shortcomings are well known in the scientific community but are – for better or worse – the best toolkit science has at its disposal today. This is however greatly exaggerated by the last (fictional) headline, which suggests that Bunsen burners in fact have a cooling effect, which is of course absolutely ridiculous, but would nevertheless change one more fundamental scientific belief drastically. Additionally, each headline contains irony or a double meaning for comical effect. The titles of five scientific articles are shown: Many commercial antibody-based immunoassays are unreliable This sentence is true. See Kebaneilwe Lebani, Antibody Discovery for Development of a Serotyping Dengue Virus NS1 Capture Assay , 2014. In this Ph.D. thesis, 11 references are given. Problems with the p-value as an indicator of significance In empirical research, one is usually interested in effects, results and relationships in a population. However, for practical reasons, only smaller subsets of populations, called samples, are available to the researcher. Usually, an effect of interest is tested using a sample. The purpose of hypothesis testing is to determine whether the observed effect (or lack of effect) in a sample is a random artifact of our particular sample, or whether there is a good chance that it also exists in the population. Generally, a null hypothesis states that there is no effect in the population while the alternative hypothesis states that there is an effect. P-values are used in hypothesis testing. The p-value is the probability of observing an effect, result or relationship in your sample data, given that no such effect, result, or relationship exists in the population. It is based on the sample data and the particular statistic (such as sample average, t or F). A statistic is the result of a calculation based on the sample. A p-value can be calculated for each statistic of interest. Formally, the p-value is the probability of observing a test statistic equal to or greater than the one based on the sample data, given that the null hypothesis is true. The threshold for p-value cutoff, α, is pre-specified (usually 5% or 1%, which is more conservative). When the p-value is lower to or equal to α, the null hypothesis is rejected in favor of the alternative hypothesis. When it is higher than α, the null hypothesis is retained. The value used for α has been proposed by Fisher and is arbitrary. The use of p-values as a measure of statistical significance is frequently criticized, for example in Hubbard & Lindsay . Randall has demonstrated this problem in the past in 882: Significant . Overfeeding of laboratory rodents compromises animal models Keenan et al. makes this case. Additionally, the word model takes on two meanings. In one sense, "model" can refer to a scientific description that makes sense of a phenomenon; in another sense, "model" can refer to an individual whose job it is to demonstrate fashions, typically fashionable outfits. Fashion models are notorious for being exceptionally thin, and so overfeeding would compromise their job as a model. Replication study fails to reproduce many published results A replication study is a study designed to duplicate the results of a previous study by using the same methods for a different set of subjects and experimenters. It aims to recreate the results to gain confidence in the results of the previous study as well as ensure that the findings of the previous study are transferable to other similar areas of study. Randall is probably referring to this recent study described in Nature: Over half of psychology studies fail reproducibility test. It might also be a reference to at least 3 studies mentioned here: http://www.jove.com/blog/2012/05/03/studies-show-only-10-of-published-science-articles-are-reproducible-what-is-happening . There is also irony in the phrasing of the title because in biology replication is a form of reproduction. Another possible interpretation of this headline is that a replication study, which may have successfully replicated the results of the specific study it was designed for, failed to reproduce the published results of many other unrelated studies. The headline is quite vague as to which results have been considered in this study. Controlled trials show Bunsen burners make things colder The theme of this comic is that commonly accepted scientific methods can be unreliable, and the joke here is that a Bunsen burner, a device intended to heat things, is newly discovered to always cool things instead, which would be absurd. In theory, yes, putting a Bunsen Burner underneath an object that's already incredibly hot would, slowly, equalize the temperature between the flame and object resulting in cooling. Given that a Bunsen Burner burns between 1000 K and 2000 K, there is probably some methodological error if the testing materials were already much hotter than the flame (more than 2000 Kelvin). It's also possible that if the "controlled trial" involved a Bunsen burner that was not lit, but was turned on to allow gas to flow, it would have a cooling effect as the gas expanded from the line pressure to atmospheric pressure. Another alternative theory is that a cold substance, such as cold water or frigid air, was fed through the burner against a warmer object. Alternatively, a trial could be set up to test something against a Bunsen burner on the one hand, and an even hotter flame on the other hand. As compared to that hotter flame, the Bunsen burner would not heat up the tested material as much, resulting in something being made "colder" than the alternative. As in the previous headline, the key to understanding the joke here is to examine the headline's ambiguity, as no clue is given about how the trials were controlled. (Title text) Careful mathematical analysis demonstrates small-scale irregularities in Gaussian distribution This is another joke of a premise that is obviously untrue. The Gaussian distribution is a mathematical construct that is generally known as the bell curve or the Normal distribution. As it is an ideal mathematical construction, by definition, it cannot have any irregularities - similar to how the equation y = 2x + 1 cannot have small-scale irregularities. The joke probably alludes to the fact that many types of observations are frequently initially modeled as a Gaussian distribution, though on careful observation the actual distribution of outcomes will often deviate from a pure Gaussian distribution. In addition, an experiment to test a Gaussian distribution will have a finite sample size, giving a non-exact Gaussian distribution. A possible paper submitted would conclude that this result is "approximately a normal distribution" with "small-scale irregularities". A news reporter without knowledge of statistics could easily misinterpret that this paper decisively concludes errors in the mathematical definitions (rather than coming from random error inherent in experimenting). [Five panels, each with the top part of a scientific article, where only the title is legible. Below is the list of authors and subheading and text in unreadable wiggles.] Many Commercial Antibody-Based Immunoassays Are Unreliable Problems With the p-Value as an Indicator of Significance Overfeeding of Laboratory Rodents Compromises Animal Models Replication Study Fails to Reproduce Many Published Results Controlled Trials Show Bunsen Burners Make Things Colder

Footprints

Footprints

https://www.xkcd.com/1575

https://www.explainxkcd.com/wiki/index.php/1575:_Footprints

[A graph is shown with a a single red line that runs through from left to right, showing different values at different times. Until the very end, the line always returns to the value 2, signifying two sets of footprints in the sand. The X-axis has a label followed by an arrow pointing right. The Y-axis has a label at the top, right of the axis, and numbers, one for each of the ticks from which five thin lines going horizontally across the entire graph. Every time the graph moves away from the value 2 there is an arrow pointing to the event and a label. The first two events has the same label. The only label below the line has five small arrows pointing to five small dips in the curve. All other labels only has one arrow pointing to one event.] X-axis: Time Y-axis: Sets of footprints 5 4 3 2 1 [The line starts at the value 2, then dips twice to the value 1. The two troughs are labeled:] Jesus carried me [The line dips once again to the value 1. The trough is labeled:] I carried Jesus [The line rises to 3 briefly, and is labeled:] Who was that guy? [The line rises to 5 sharply, and then falls in a sharp staircase pattern, labeled:] Ducklings imprinted on Jesus and followed him around [The line rises to 4, labeled:] Got lost and followed our own footprints [The line dips for very short periods five times to the value 1. The first dip is between "I carried Jesus" and "Who was that guy?", the second between "Who was that guy?" and "Duckings imprinted on Jesus..." and the final three are all between the "Ducklings imprinted on Jesus..." and "Got lost and followed our own footprints". These five troughs share one label with five arrows from the same text:] Jesus disappeared for an evening each time a new Twilight movie came out [The line dips to 1, labeled:] Rode around with Jesus in captured AT-ST [The line dips and stays level at 1, labeled:] Hit quicksand patch. Jesus didn't make it :( [The line dips to zero at the end, and is labeled:] Went home

The comic is a satirical graphical representation of the inspirational Christian poem " Footprints ," which has been recounted in many versions and is of disputed authorship. The basic idea of the poem is that the narrator looks back at scenes of his life and sees two sets of footprints, his and those of Jesus. During the most difficult times of his life, the narrator sees only one set of footprints and assumes that Jesus had left him during those times. In the climax of the poem, Jesus responds to the narrator that he saw only one set of footprints during the most difficult times of his life because Jesus was carrying him during those times. The poem is seen by many as overly sentimental and is thus ripe for parody of this kind. The graph mockingly illustrates various times when Jesus or the narrator left the scene, or otherwise gives various reasons why the number of footprints may have been other than two. "Ducklings imprinted on Jesus and followed Him around" is a reference to Konrad Lorenz 's experiments. Three ducklings followed Jesus and the narrator. "Jesus disappeared for an evening each time a new Twilight movie came out" could mean that Jesus went to see the movie and left the narrator alone. It could also mean that his support of people through their most difficult trials meant he had to carry a lot of emotionally scarred people. "Got lost and followed our own footprints" may be a reference to " Winnie-the-Pooh " (1926), in which the titular bear and his friend try and hunt a "Woozle" by its footprints, actually following their own round and round a spinney, which also seems slightly childish for Jesus as traditionally portrayed. An alternate explanation is that they came to a dead end, and had to double back. "Rode around with Jesus in captured AT-ST " is a reference to a two-legged combat "walker" from Star Wars. The implication is that Jesus would have participated in forcibly taking a war machine, which appears somewhat out of character. The reference at the end to Jesus drowning in a patch of quicksand, and then the narrator simply going home, again subverts the poem's earnestness. "Going home" may be a reference to dying, implying that the narrator died without Christ, or that the narrator and Christ were not traveling anymore. It is also possible that this is meant literally, and the narrator actually went home. The title text continues the parody by imagining that Jesus delivers the poem's climactic lines in stereotypical "bro" speak, a dialect perceived by many to be obnoxious. The reference to punching Jesus is possibly another reference to the poem's perceived excessive sentimentality. Another interpretation is that the narrator, like many people, dislikes usage of this lingo and punched Jesus as a result of this hatred. This might also be a pun on "totes;" with tote bags being used to carry things. The narrator punching Jesus might be because of his hatred for the pun. Yet another interpretation is that Jesus' obnoxious way of explaining himself indicated dishonesty, meaning he did not in fact carry the narrator during the most difficult parts of his life. The narrator sensed this and punched Jesus in retaliation. "There's one set of foot-p's cause I was totes carrying you, bro!" can be translated into normal English as "There's one set of footprints because I was definitely carrying you, friend!". An alternate explanation of some of the oddities of the strip is that "Jesus" is not Jesus Christ, but some guy merely named Jesus, as is common in some Latin American countries. Using the Twilight movies as reference points, it can be determined that the span of the graph is from approximately early 2004 to late 2018, with Jesus' death in the second half of 2017. The poem has appeared in xkcd before, at 1110 with coordinates 0.7601, -58.803. [A graph is shown with a a single red line that runs through from left to right, showing different values at different times. Until the very end, the line always returns to the value 2, signifying two sets of footprints in the sand. The X-axis has a label followed by an arrow pointing right. The Y-axis has a label at the top, right of the axis, and numbers, one for each of the ticks from which five thin lines going horizontally across the entire graph. Every time the graph moves away from the value 2 there is an arrow pointing to the event and a label. The first two events has the same label. The only label below the line has five small arrows pointing to five small dips in the curve. All other labels only has one arrow pointing to one event.] X-axis: Time Y-axis: Sets of footprints 5 4 3 2 1 [The line starts at the value 2, then dips twice to the value 1. The two troughs are labeled:] Jesus carried me [The line dips once again to the value 1. The trough is labeled:] I carried Jesus [The line rises to 3 briefly, and is labeled:] Who was that guy? [The line rises to 5 sharply, and then falls in a sharp staircase pattern, labeled:] Ducklings imprinted on Jesus and followed him around [The line rises to 4, labeled:] Got lost and followed our own footprints [The line dips for very short periods five times to the value 1. The first dip is between "I carried Jesus" and "Who was that guy?", the second between "Who was that guy?" and "Duckings imprinted on Jesus..." and the final three are all between the "Ducklings imprinted on Jesus..." and "Got lost and followed our own footprints". These five troughs share one label with five arrows from the same text:] Jesus disappeared for an evening each time a new Twilight movie came out [The line dips to 1, labeled:] Rode around with Jesus in captured AT-ST [The line dips and stays level at 1, labeled:] Hit quicksand patch. Jesus didn't make it :( [The line dips to zero at the end, and is labeled:] Went home

I Could Care Less

I Could Care Less

https://www.xkcd.com/1576

https://www.explainxkcd.com/wiki/index.php/1576:_I_Could_Care_Less

[The first three panels are slim compared to the next row below, and they only takes up the same space as the first two of the three panels below this row. Similarly the bottom row, also with three panels, take up less space, although more than the top row. But in this bottom row the empty space in the comic is to the left vs. to the right in the top row.] [Megan and Ponytail are walking together, Megan in front holds her arms out to the side.] Megan: ...Anyway, I could care less. [Zoom in on Ponytail holding up her hand (which can atypically be seen), finger pointing up.] Ponytail: I think you mean you couldn't care less. Saying you could care less implies you care at least some amount. [Back to Megan and Ponytail walking, both have their arms down.] Megan: I dunno. [The next panel supposed to be to the right of this is missing, instead the comic jumps to the next row. This fourth panel has inverted brightness, with a white Megan floating in a black void, with white text above her.] Megan: We're these unbelievably complicated brains drifting through a void, trying in vain to connect with one another by blindly flinging words out into the darkness. [Back to Megan and Ponytail walking.] Megan: Every choice of phrasing and spelling and tone and timing carries countless signals and contexts and subtexts and more, Megan: and every listener interprets those signals in their own way. Megan: Language isn't a formal system. Language is glorious chaos. [Zoom in on Megan's head.] Megan: You can never know for sure what any words will mean to anyone. Megan: All you can do is try to get better at guessing how your words affect people, so you can have a chance of finding the ones that will make them feel something like what you want them to feel. Megan: Everything else is pointless. [They have stopped walking as Megan holding a hand out has turned around facing Ponytail.] Megan: I assume you're giving me tips on how you interpret words because you want me to feel less alone. Megan: If so, then thank you. Megan: That means a lot. [Megan and Ponytail resume with their walking.] Megan: But if you're just running my sentences past some mental checklist so you can show off how well you know it, [Megan and Ponytail continue walking.] Megan: then I could care less.

However, linguists point out that the strict application of logic to an idiom is inappropriate: many expressions seem on the surface to mean the opposite of the meaning they are used to convey (e.g. "head over heels"), and they defend "I could care less" on those grounds . The psychologist Steven Pinker argues in The Language Instinct that the phrase is sarcastic (cf. "Big deal!"), while linguist John Lawler explains it as a "Negative Polarity Item," a phrase that is practically only used in negated form, allowing the explicit negation to be omitted (a pattern often found in French). In this comic, Megan feels alone because there is unavoidable difference between her understanding of her own words and the listener's interpretation, so while she sees discussion of semantics as being of potentially high social and emotional value, she doesn't think it has objective value. However, ironically, at the end of the comic, the meaning of "I could care less" with regards to Ponytail's behavior is ambiguous: either Megan is brushing off Ponytail's pedantry because she doesn't care about it (she couldn't care less) or she is hurt by Ponytail's focus on the details of her words rather than the emotional cues she should have learned over the course of their relationship (she actually could care less). The title text refers to another word often used in ways some consider incorrect: "literally" (see 725: Literally ). The sentence is also ambiguous, as it may mean that 'literally' or 'figuratively,' the speaker could or couldn't care less. Further, it implies that Randall considers the argument over whether literally may be properly used to mean 'figuratively' is petty in the same way. Later in 1735: Fashion Police and Grammar Police Ponytail is once again on the side of the grammar police and also in this comic the word literally is used. Alternatively, it could mean that Megan cares too much about Ponytail's correction, considering her response to it. In a further alternative, the title text could amount to a self-ironical evaluation on Randall’s part to the effect that he himself might be devoting too much of his time and energy to the meaning of the phrase in question, as evidenced by the comic itself. The inverse image of Megan floating through space in the fourth panel, as well as her long introspection, is a reference to the five-part "Choices" series, starting at 264: Choices: Part 1 . [The first three panels are slim compared to the next row below, and they only takes up the same space as the first two of the three panels below this row. Similarly the bottom row, also with three panels, take up less space, although more than the top row. But in this bottom row the empty space in the comic is to the left vs. to the right in the top row.] [Megan and Ponytail are walking together, Megan in front holds her arms out to the side.] Megan: ...Anyway, I could care less. [Zoom in on Ponytail holding up her hand (which can atypically be seen), finger pointing up.] Ponytail: I think you mean you couldn't care less. Saying you could care less implies you care at least some amount. [Back to Megan and Ponytail walking, both have their arms down.] Megan: I dunno. [The next panel supposed to be to the right of this is missing, instead the comic jumps to the next row. This fourth panel has inverted brightness, with a white Megan floating in a black void, with white text above her.] Megan: We're these unbelievably complicated brains drifting through a void, trying in vain to connect with one another by blindly flinging words out into the darkness. [Back to Megan and Ponytail walking.] Megan: Every choice of phrasing and spelling and tone and timing carries countless signals and contexts and subtexts and more, Megan: and every listener interprets those signals in their own way. Megan: Language isn't a formal system. Language is glorious chaos. [Zoom in on Megan's head.] Megan: You can never know for sure what any words will mean to anyone. Megan: All you can do is try to get better at guessing how your words affect people, so you can have a chance of finding the ones that will make them feel something like what you want them to feel. Megan: Everything else is pointless. [They have stopped walking as Megan holding a hand out has turned around facing Ponytail.] Megan: I assume you're giving me tips on how you interpret words because you want me to feel less alone. Megan: If so, then thank you. Megan: That means a lot. [Megan and Ponytail resume with their walking.] Megan: But if you're just running my sentences past some mental checklist so you can show off how well you know it, [Megan and Ponytail continue walking.] Megan: then I could care less.

Advent

Advent

https://www.xkcd.com/1577

https://www.explainxkcd.com/wiki/index.php/1577:_Advent

[Cueball is looking at a large wall subdivided into a rectangular 20 x 12 grid, with each grid subdivided into 10x7 small drawers. Below the frame there is a caption:] Unsettling gift: Life expectancy Advent calendar

An Advent calendar is usually a means of celebrating the days before Christmas. Each day on the calendar is represented by a "door" (a flap of card), behind which is usually a picture related to the Christian nativity, a picture of commercial Christmas (e.g. a present), a small chocolate, or a small gift. This comic satirizes the concept by proposing such a calendar that would have one gift for each day one is anticipated to live. Such a calendar would be very morbid and existential. This is especially disturbing when given as a gift because it implies someone has put extensive thought into when the recipient will die. In Cueball's case, assuming each square in the calendar represents one day, the wall he is facing is the entire present he received and the boxes just out of view follow the same pattern, the entire wall represents 16,800 days (a large grid of 12x20 smaller grids of 10x7 boxes: 12×20×10×7 = 16,800), i.e. just under 46 more years (16,800/365.25 = 45.99589). Assuming that Cueball is a male from the US and the grid represents his life expectancy, according to American Official Social Security Actuarial Life Table for males, he is probably 31.9 years old . This would make Cueball almost exactly one year older than Randall , who was born October 17, 1984 making him 30.9 years old when he wrote this comic. Due to the non-linear shape of the mortality curve, the chance of Cueball making it to the end of his calendar is 57.7%, at which point he will need to get another calendar but with only 9.2 years worth of doors. The title text refers back to a standard advent calendar by saying that the Christmases are specially marked; on a traditional Advent calendar, only the 1st to the 24th of December have doors, however in recent times, Advent calendars often also include an additional door for the day after Advent, Christmas Day. A few dozen may be any small number of dozens, and 3 5/6 dozens (46) is aptly described by a few dozen ; see 1070: Words for Small Sets . Any dictionary (for example Oxford Learner's Dictionaries ) says that a dozen may be an approximate number, not exactly 12. A completely different advent calendar was mentioned in 994: Advent Calendar . Similar calendars have been mentioned in the blog Wait But Why in the 2014 post Your Life in Weeks , and in equally geeky webcomic Abstruse Goose , in the 2008 post 936 Little Blobs . [Cueball is looking at a large wall subdivided into a rectangular 20 x 12 grid, with each grid subdivided into 10x7 small drawers. Below the frame there is a caption:] Unsettling gift: Life expectancy Advent calendar

Squirrelphone

Squirrelphone

https://www.xkcd.com/1578

https://www.explainxkcd.com/wiki/index.php/1578:_Squirrelphone

[Cueball is approaching a stump with a squirrel perched on it. A ringing noise is coming from the squirrel's back.] Squirrel: Riiiiing Squirrel: Riiiiiing [Cueball has picked up the squirrel and is holding it to his left ear.] Cueball: Hello? [The squirrel bites Cueball's head.] Squirrel: Chomp! Cueball: Ow! [Cueball holds his hand to his cheek while the squirrel leaps away, fleeing.] Cueball: ???

"Squirrelphone" is a compound word combining " squirrel " and " phone ". In this comic, we see a squirrel pretend to be a telephone, only to bite Cueball when he tries to pick it up and use it as one. This is humorous because a living squirrel is not an appropriate creature to maintain a phone call [ citation needed ] . This could be seen as an example of mimicry in nature, or parasitism where one creature gains a benefit from another. It may be an allusion to the vampire squirrel which was documented recently that allegedly 'attacks and kills' deer. The comic follows the absurd conclusion that the squirrel uses mimicry to 'attack and kill' humans. Cueball may be lucky to still be alive [ citation needed ] . Another possibility is that the squirrel thought that Cueball was trying to eat it because Cueball picked it up and put it near his mouth, so it bit Cueball in self-defense. If this is the case, then biting Cueball can be said to have worked, as Cueball did relase the squirrel, as shown in panel four. However, this fails to explain why the squirrel was imitating a phone, which would make a human more likely to pick the squirrel up, so Randall was more likely trying to reference the recent vampire squirrel documentation. The sounds the squirrel makes correspond to the tones that the terminals make when you use the POTS (Plain Old Telephone Service) in the US: Squirrels have been used frequently in xkcd, also in what if , where it has for instance been used as a cute animal to replace a drawing of something scary or unpleasant like in Blood Alcohol or Cannibalism . So this is some twist for the cuteness factor of squirrels in xkcd. It may also be the case that "squirrelphone" is a reference to the popular web-mail software SquirrelMail . The title text takes the joke further by showing the squirrel possesses another phone feature: that cordless phones need to recharge frequently, either by setting them at their cradles or by connecting them to a charger, in the case of mobile phones. When they sense the battery is low, they emit a beeping noise every few minutes. In this case, the stump is the squirrel's cradle. However, the reason that cordless phones beep when they are getting low on battery is in order to alert humans to move them to the charging cradle because the phones cannot move themselves. On the other hand, squirrels can move on their own without needing humans to pick them up, [ citation needed ] so the squirrel likely only does it in order to trick people into picking it up, which further suggests that it is a vampire squirrel. [Cueball is approaching a stump with a squirrel perched on it. A ringing noise is coming from the squirrel's back.] Squirrel: Riiiiing Squirrel: Riiiiiing [Cueball has picked up the squirrel and is holding it to his left ear.] Cueball: Hello? [The squirrel bites Cueball's head.] Squirrel: Chomp! Cueball: Ow! [Cueball holds his hand to his cheek while the squirrel leaps away, fleeing.] Cueball: ???

Tech Loops

Tech Loops

https://www.xkcd.com/1579

https://www.explainxkcd.com/wiki/index.php/1579:_Tech_Loops

[A flow chart 18 boxes linked (or not) with arrows going in several different directions. At the top is an arrow pointing to the right with text under. The rest of the text in the chart is written inside the boxes.] [Under arrow:] Supports [Going from the top below the tip of the arrow and reading left to right and top to bottom the following text is written in the boxes that all are in some way connected with each other. The number of arrows going in and out of each box is noted behind the text in square brackets as [in, out]:] Updater [1, 3] Tool [1, 1] Tool [1, 1] Repository [3, 0] Library [1, 1] Library [2, 3] Library [1, 1] Chat Client [2, 1] VM [2, 1] IRC for some reason [1, 1] Custom Settings [1, 1] Hardware Workaround [1, 2] Library [1, 1] Awful hack from 2009 [3, 3] Library [1, 1] Library [0, 1] [The last box in the lower middle is not connected to any other boxes but has two exit arrows pointing to two questionmarks.] DLL needed by something [0, 2] ? ? [Box alone at the top right corner, with no connections:] Things I actually want to use my computer for [0, 0] [Caption below the panel:] Every now and then I realize I'm maintaining a huge chain of technology solely to support itself.

The comic is about how much time a geek might spend on a computer just to maintain the system itself, rather than actually using it for something relevant. This can in the worst cases go all the way up to the point where maintaining the system becomes the main goal. Often the operating system (OS) needs periodic updates, which might break some apps which in turn need to be updated; apps themselves might need to be updated, which can create all sort of incompatibilities which the geek then needs to spend time fixing. One term for this is " dependency hell ". Most people consider computers as tools to achieve something else — e.g. to surf the web, play games, read news or balance their bank account — and they would rather not have to spend lots of time on maintaining the OS or the computer if they can avoid it. Here, however, Randall finds he's spending most of the time using his computer just for the sake of maintaining the OS or the hardware on said computer. It's tools for the sake of tooling, rather than tools as helpers to build something else. A hardware equivalent would be the RepRap Project : get a 3D printer and end up spending all the time printing 3D parts for itself instead of creating something else like toys or art. An alternative interpretation is how a simple task can get maddeningly tricky because of the inherent complexity of the system. An example of this appears in 949: File Transfer , where the simple task of sending a file from one computer to another gets practically impossible despite having all kinds of cloud tools available, many of them designed to perform much more complex tasks with one simple click. In this view, the box labeled "things I actually want to use my computer for" could refer to simple actions like transferring a file and all the rest of the graph are unsuccessful tiring attempts to solve the problem by installing increasingly complex tools which end up not solving the simple problem properly. This is similar to this traditional programming joke . In the title text Randall realizes that what he really wishes to do it often only to learn about and discussing new tools to improve the chain. So in this way it is for sure only a system to support itself. But on the other hand, then the box with things he actually wishes to use the computer for, is then not disconnected from the rest, but an integral part of it all. Other comics about the same concept are 349: Success and 763: Workaround . There are 18 boxes in the chart, but only 12 different texts. 16 of the boxes are interconnected. Two are not connected to any other boxes. Here is a list of all the items explained individually: The flow chart described: → means supports (key) Things I actually want to use my computer for [isolated box with no links into or out of, by any of the following] DLL needed by something → ? [two exits to unknowns] Library (1) → Awful hack from 2009 → Awful hack from 2009 → IRC for some reason → Awful hack from 2009 → (Loop) Awful hack from 2009 → Library (2) → Library (3) → Repository Awful hack from 2009 → Library (4) → Library (5) → Custom Settings → Library (6) → Library (6) → Chat Client → Repository Library (6) → Hardware Workaround → Hardware Workaround → VM → Chat Client → Repository Hardware Workaround → Awful hack from 2009 → (Loop) Library (6) → Tool (1) → Updater → Updater → Repository Updater → Library (6) → (Loop) Updater → Tool (2) → VM → Chat Client → Repository (Note the Repository node leads to nowhere) [A flow chart 18 boxes linked (or not) with arrows going in several different directions. At the top is an arrow pointing to the right with text under. The rest of the text in the chart is written inside the boxes.] [Under arrow:] Supports [Going from the top below the tip of the arrow and reading left to right and top to bottom the following text is written in the boxes that all are in some way connected with each other. The number of arrows going in and out of each box is noted behind the text in square brackets as [in, out]:] Updater [1, 3] Tool [1, 1] Tool [1, 1] Repository [3, 0] Library [1, 1] Library [2, 3] Library [1, 1] Chat Client [2, 1] VM [2, 1] IRC for some reason [1, 1] Custom Settings [1, 1] Hardware Workaround [1, 2] Library [1, 1] Awful hack from 2009 [3, 3] Library [1, 1] Library [0, 1] [The last box in the lower middle is not connected to any other boxes but has two exit arrows pointing to two questionmarks.] DLL needed by something [0, 2] ? ? [Box alone at the top right corner, with no connections:] Things I actually want to use my computer for [0, 0] [Caption below the panel:] Every now and then I realize I'm maintaining a huge chain of technology solely to support itself.

Travel Ghost

Travel Ghost

https://www.xkcd.com/1580

https://www.explainxkcd.com/wiki/index.php/1580:_Travel_Ghost

[Cueball, holding a smartphone, is talking to White Hat.] Cueball: Lots of apps let you plan your trips using real-time bus, train, and traffic data. They try to predict which route will be faster, but aren't always right. [Cueball continues to talk off-panel. The text is above a map showing three possible routes with an overlaid Cueball on each; the top and the bottom route and Cueball are faded and the middle is black up until the black Cueball. After that this route is also faded. A black point on the right indicates the destination.] Cueball (off-panel): Instead of just planning , my new app lets you send "ghost" versions of you along different routes, simulating their travel using the real-time data [Cueball, again talking to White Hat, holding the smartphone down.] Cueball: That way, you can see which route turned out to be faster in practice, Cueball: You can also race your past selves. [Cueball is getting out of his car holding his smartphone in one hand and a briefcase in the other; A faded out Cueball bicyclist is in front of him to the right. At the top there is a caption in a frame: Soon... Cueball: Ugh, lost to the bike ghost again. [Cueball with his briefcase is outside a door, holding a key card up to a key reader. On the inside of the door Ponytail is facing the door and points toward the faded version of Cueball also holding a briefcase.] Cueball: Hey, my key won't work Ponytail: I'm sorry, but we've decided to replace you. This floaty guy is much more punctual. Cueball: But... [Science Girl and another girl with wavy long hair, is holding faded out Cueball's hands. The real Cueball is standing to the right, next to his briefcase on the ground. He is holding his hands out towards his kids.] Science Girl: Our new dad never misses our games! Cueball: Nooo!

In racing game , a " ghost " is a common term for the recording of a player's best actions. The recording is used to create a virtual racer that another player can compete against. The previous player is shown as ghostly and transparent, because it is only a recording of a previous game and it does not interact in any way with the game currently being played. Certain models of cycling also use this concept to motivate athletes while training. A mapping app, such as Google Maps , attempts to plot the fastest route from one place to another, but there's no way to tell which route is really the fastest without testing it. So, Cueball has created an app that will simulate a number of different routes and produce "ghosts" from them. He hopes to use this app to discover the fastest route by competing against his ghosts like a racing game. He brags about this app to his friend White Hat . However, the comic takes a turn for the absurd when it depicts actual ghosts competing with him, instead of simulations on his phone. Soon enough, he is fired from work because one of his "ghosts" is more punctual than he is. And even worse his children apparently comes to prefer the more punctual "ghosts" over him as this version of daddy never misses their games. (The girls could be the same as those in the 1659: Tire Swing ). In the title text this is even taken into the bedroom, although it is a different ghost than the one preferred by the children. This is likely a subtle reference to euphemisms for sexual climax, such as "arrival", with delayed ejaculation generally preferred. It should be noted that this app would not guarantee the minimum travel time. The user doesn't find out which route was fastest until after the first ghost has arrived. But as the current traffic situation will have changed by then, that route will not necessarily still be the fastest. [Cueball, holding a smartphone, is talking to White Hat.] Cueball: Lots of apps let you plan your trips using real-time bus, train, and traffic data. They try to predict which route will be faster, but aren't always right. [Cueball continues to talk off-panel. The text is above a map showing three possible routes with an overlaid Cueball on each; the top and the bottom route and Cueball are faded and the middle is black up until the black Cueball. After that this route is also faded. A black point on the right indicates the destination.] Cueball (off-panel): Instead of just planning , my new app lets you send "ghost" versions of you along different routes, simulating their travel using the real-time data [Cueball, again talking to White Hat, holding the smartphone down.] Cueball: That way, you can see which route turned out to be faster in practice, Cueball: You can also race your past selves. [Cueball is getting out of his car holding his smartphone in one hand and a briefcase in the other; A faded out Cueball bicyclist is in front of him to the right. At the top there is a caption in a frame: Soon... Cueball: Ugh, lost to the bike ghost again. [Cueball with his briefcase is outside a door, holding a key card up to a key reader. On the inside of the door Ponytail is facing the door and points toward the faded version of Cueball also holding a briefcase.] Cueball: Hey, my key won't work Ponytail: I'm sorry, but we've decided to replace you. This floaty guy is much more punctual. Cueball: But... [Science Girl and another girl with wavy long hair, is holding faded out Cueball's hands. The real Cueball is standing to the right, next to his briefcase on the ground. He is holding his hands out towards his kids.] Science Girl: Our new dad never misses our games! Cueball: Nooo!

Birthday

Birthday

https://www.xkcd.com/1581

https://www.explainxkcd.com/wiki/index.php/1581:_Birthday

[Caption above the frame:] xkcd turns 10 years old this month. In light of last night's court ruling in Rupa Marya v. Warner/Chappell Music Inc. , I would just like to say: [The song text is written, with nine musical notes, three groups on each side of the text, above a birthday cake with 10 lit candles. The cake has two distinct layers. On each layer there are drawn 6 xkcd stick figures with small black bullets between them. The center bullet in the bottom layer is shaped like a heart. The figures at the edges can be difficult to recognize. The figures in the upper layer and from the left are: A man with a hat (hard to see if it is one of the recognized characters), White Hat, Megan, Pony Tail, Hairy and Cueball (hard to see him properly). Similar in the lower layer: Black Hat, Danish, Beret Guy, Rob, Cutie, and a girl (hard to see, but looks like girls hair, not a hat).] Happy birthday to you Happy birthday to you Happy birthday, dear xkcd Happy birthday to you

xkcd turns 10 years old on September 30, 2015 (a week after the release of this comic). In this comic Randall honors his webcomic by singing to it the classic " Happy Birthday to You " song. " Happy Birthday to You " is one of the most commonly sung songs in the English language (and is common in many others). Because of its age, ubiquity and simplicity, it has long surprised people to learn that it was not in the public domain. Warner/Chappell Music claimed the copyright to the lyrics, and has demanded royalties for any recording, publication or public performance for commercial purposes. Total revenues for this song were estimated at US$2 million annually. This strip refers to a ruling, from the day before the release of this comic, by a federal judge in California ( George King ), stating that the song is not covered by a valid copyright (see Warner's 'Happy Birthday' Copyright Not Valid, Judge Rules ). This ruling resulted from a lawsuit filed by Good Morning To You Productions (singer Rupa Marya and filmmaker Robert Siegel ) against Warner/Chappel Music to declare Warner/Chappel's copyright claim in the song invalid (filing at [1] ). With this ruling, the court declared that Warner/Chappell does not have a copyright claim to the song, and therefore the song can now be sung or published by anyone, in any context, without having to pay royalties to Warner/Chappell. The ruling does not go so far as to declare the song to be in the public domain, leaving it more correctly defined as an orphan work . Randall seems to be celebrating the fact that this strip, which would have put him at risk for a lawsuit the day before, is now unlikely to be challenged since the odds of a new party appearing and successfully claiming copyright on the lyrics and subsequently demanding license fees is approximately zero. The title text is a joke that refers to Randall calling the police against Chuck E. Cheese's as well as his own friends and parents when they sang "Happy Birthday" and did not pay royalties. The song is very commonly used in entertainment restaurants, such as Chuck E. Cheese's, and at both grown-ups' and children's birthdays. Because restaurants are commercial enterprises, public performances of the song, prior to this ruling, would potentially have exposed the restaurant to liability claims (though singing it at a private birthday party would not). In either case, calling the police would be an extreme overreaction. However, many restaurants (for example, Olive Garden ) actually have staff sing a special birthday song (not Happy Birthday To You ) to avoid having to pay royalties. [Caption above the frame:] xkcd turns 10 years old this month. In light of last night's court ruling in Rupa Marya v. Warner/Chappell Music Inc. , I would just like to say: [The song text is written, with nine musical notes, three groups on each side of the text, above a birthday cake with 10 lit candles. The cake has two distinct layers. On each layer there are drawn 6 xkcd stick figures with small black bullets between them. The center bullet in the bottom layer is shaped like a heart. The figures at the edges can be difficult to recognize. The figures in the upper layer and from the left are: A man with a hat (hard to see if it is one of the recognized characters), White Hat, Megan, Pony Tail, Hairy and Cueball (hard to see him properly). Similar in the lower layer: Black Hat, Danish, Beret Guy, Rob, Cutie, and a girl (hard to see, but looks like girls hair, not a hat).] Happy birthday to you Happy birthday to you Happy birthday, dear xkcd Happy birthday to you

Picture a Grassy Field

Picture a Grassy Field

https://www.xkcd.com/1582

https://www.explainxkcd.com/wiki/index.php/1582:_Picture_a_Grassy_Field

[Megan and Cueball are walking together.] Megan: Picture a grassy field. Megan: In the center sits a small, pale, big-eyed creature with the power to escape from any visualized scene and move freely through the brain that imagined it. Megan: It glances around nervously and- Megan: -whoops, where'd it go? Megan: Sorry about that! Keep an eye out for it in your daydreams.

In this comic Megan asks Cueball to picture himself in a grassy field. It is a standard technique to begin a visualization by asking the person to imagine that they are in some calm environment (could be for any kind of meditation / mindfulness like for instance yoga ). A grassy field could have been replaced by a beach at the sea, or a forest with sunbeams coming down through the trees. Proceeding with the visualization Megan asks Cueball to imagine a creature with the power to be able to escape from any visualized scene, and then tries to convince him that this creature has indeed escaped from his current visualization as it indeed would be able to do. She then proceeds by apologizing for this, but then tells him (warns him) that it from now on might appear in Cueball's daydreams, so he should begin looking out for it. This indicates that she is not at all sorry, but did this intentionally to try and mess with Cueball's head. The idea of the possibility of escaping an imagined situation was already used in 248: Hypotheticals . Now that Megan has introduced both the idea of the creature and the idea that it may appear in his daydreams, Cueball will almost certainly think of it from time to time, creating a self-fulfilling prophecy. In the title text Megan proposes a solution to get rid of the creature in Cueball's daydream, namely by picturing the only creature that the first fears. However, if this new (maybe quite scary) creature should be able to pursue the original creature, then it would also have to be able to move through visualized scenes just as easily. And this is what Megan pretends happens again. So now the problem is that Cueball has two creatures on the loose in his daydreams. And even if the second scares the first away, he would then still have the new one to worry about. [Megan and Cueball are walking together.] Megan: Picture a grassy field. Megan: In the center sits a small, pale, big-eyed creature with the power to escape from any visualized scene and move freely through the brain that imagined it. Megan: It glances around nervously and- Megan: -whoops, where'd it go? Megan: Sorry about that! Keep an eye out for it in your daydreams.

NASA Press Conference

NASA Press Conference

https://www.xkcd.com/1583

https://www.explainxkcd.com/wiki/index.php/1583:_NASA_Press_Conference

[Cueball is standing behind a lectern with the NASA logo on it.] Cueball: That concludes the press conference. Any questions? Cueball: Yes, you, from... it just says "The News"? [Beret Guy is standing in a crowd holding a microphone.] Beret Guy: Hi! I have a microphone so I'm real loud now. Beret Guy: How does this Mars data compare to data from other fields? Like medicine? Or sports? Cueball (offscreen): That question makes no sense. Beret Guy: If there's water on Mars, is it ruined? Beret Guy: Or will it be okay when it dries out? Cueball (offscreen): Any other questions? [The shot zooms out, showing that Cueball and the lectern is standing on a podium and also the crowd comes in to view.] Beret Guy: What were those guys hassling Luke in the Mos Eisley Cantina trying to accomplish? I felt like I was supposed to understand that. Cueball: Anyone else? Ponytail: That's now my question, too. Megan: Were they just picking a fight? Ponytail: If so, why did...

This comic is a reference to the press conference held by NASA on 28th September 2015, (the same day this comic was published), which confirmed the existence of liquid water at the surface of Mars . The comic was posted before the NASA press conference was held, although speculation about the announcement had already occurred. The "questions" portion of the press conference is derailed by Beret Guy , acting as a reporter for a network known only as "The News". He first comments he is holding a microphone so he is "real loud now." He then asks how the data about Mars relates to data in other fields like medicine and sports. This may seem like an intelligent question upon first glance, but it is in fact nonsensical. Afterwards he asks if Mars has been "ruined" by getting wet, or if Mars will be okay when it dries out. Some things, e.g. indoor furniture, can be damaged by water, but Mars is not one of those things [ citation needed ] . When asked if he has any other questions he asks why Luke Skywalker was being hassled at the Mos Eisley Cantina in Star Wars . ( Dr. Evazan and Ponda Baba simply told Luke that "[they] don't like [him]", but Beret Guy is evidently not satisfied by that explanation.) Although this may be somewhat space-related, NASA is not an organization that explains films, whether or not they are space related. The other reporters forget their original questions and join in on the irrelevant discussion, much to the dismay of the NASA scientist. This is probably meant to mock previous NASA press conferences, where reporters have asked inane questions that reveal their total ignorance of the field. The title text refers to Elon Musk , who suggested nuking Mars as a faster way of warming it up to make it habitable. [Cueball is standing behind a lectern with the NASA logo on it.] Cueball: That concludes the press conference. Any questions? Cueball: Yes, you, from... it just says "The News"? [Beret Guy is standing in a crowd holding a microphone.] Beret Guy: Hi! I have a microphone so I'm real loud now. Beret Guy: How does this Mars data compare to data from other fields? Like medicine? Or sports? Cueball (offscreen): That question makes no sense. Beret Guy: If there's water on Mars, is it ruined? Beret Guy: Or will it be okay when it dries out? Cueball (offscreen): Any other questions? [The shot zooms out, showing that Cueball and the lectern is standing on a podium and also the crowd comes in to view.] Beret Guy: What were those guys hassling Luke in the Mos Eisley Cantina trying to accomplish? I felt like I was supposed to understand that. Cueball: Anyone else? Ponytail: That's now my question, too. Megan: Were they just picking a fight? Ponytail: If so, why did...

Moments of Inspiration

Moments of Inspiration

https://www.xkcd.com/1584

https://www.explainxkcd.com/wiki/index.php/1584:_Moments_of_Inspiration

[Isaac Newton, with curly long hair, sits under a tree. A waning crescent moon can be seen. An apple falls and hits him on the head. There is a caption in a frame that breaks the top border of the main frame:] Isaac Newton Apple falling: Bonk Isaac Newton: Ow! [Isaac Newton rubs his sore head.] Isaac Newton: Aha! [Cueball throws a baseball towards Lise Meitner with short dark hair. (The ball can be seen in the next frame). She turns towards him too late to react and completely fails to even try catching the ball. There is a caption in a frame that breaks the top border of the main frame:] Lise Meitner Cueball: Hey Lise! Think fast! Ball hitting something (off-screen): Crash [Lise takes her hands to her mouth and she watches the broken porcelain atom lying in two pieces on the floor where it has fallen off a desk. On the desk, three other intact atoms can be seen. The baseball lies behind her.] Lise Meitner: Oh no! My collection of porcelain atoms! Lise Meitner:...Hmm. [Four kids are standing in front of Megan and Charles Darwin (with a big beard and hair behind the ears). All the kids are trying to drink a glass of soda with a straw in them. The first kid is a boy with dark flat hair and sips soda through the straw with his mouth. The next kid is a boy with standing black hair, he tries in vain to drink with his beak open on each side of the glass. The third kid is a girl with her hair in a bun. She tries to get her beak into the glass which she has put on the floor. The last kid is a boy version of Cueball who slurps his soda through the straw. There is a caption in a frame that breaks the top border of the main frame:] Charles Darwin Megan: I gave our kids soda, but the ones with beaks always have trouble drinking it. Charles Darwin: I've noticed that... Boy with flat dark hair: Sip sip Boy with standing black hair and a beak: Crunch Girl with her hair in a bun and a beak: Peck peck Cueball like kid: Sluurp [A hairy guy is standing in front of Albert Einstein (with wild hair and a mustache), who is holding one hand to his head and has a clock in his other hand. Behind them is a train, with a locomotive at the front and a wagon behind that stretches beyond the frame. Another hairy guy has his head out of the front window of the wagon and is flashing a light towards the other two. In the next three windows can be seen passengers, two with Cueball like heads and one with hair. There is a caption in a frame that breaks the top border of the main frame:] Albert Einstein Albert Einstein: I wish your twin brother would stop shining lights at us from that train. I can barely see my clock! Albert Einstein: ...Wait! This comic appeared on xkcd's ten-year anniversary.

Isaac Newton 's original examples describing the force of gravity show an apple falling from a tree in order to explain why the apple falls toward the Earth, instead of the Earth falling toward the apple. He is often said to have been inspired by watching falling apples ; in common folklore, this developed into the legend that he was actually struck by an apple. The first part of this comic retells that famous legend. The later panels depict similar (but more and more implausible) legends that could emerge if we were to assume that other scientists' most famous examples and discoveries were based on actually observing some mundane everyday event taking place. In the first situation, we not only see the apple fall on Newton's head, we also see the Moon. This was one of the first astronomical objects on which he used his theory of gravity. He calculated its orbit around the Earth and found that it fit with the theory. In the second situation, Cueball throws a baseball towards Lise Meitner , but when she fails to catch the ball it hits one of her porcelain model-atoms. In this way, Meitner discovered a way to split the atom. Cueball may represent Otto Hahn , since they were part of the Hahn-Meitner-Strassmann team that worked on this problem. Hahn was later awarded the Nobel Prize for Chemistry, where Meitner was overlooked. Throwing something at someone and asking them to think fast is a common "joke", where the receiver rarely has a chance to actually catch the object. But in this case, it could also be a reference to the fact that she then thought fast then made a major discovery. Or if it is Hahn, then he thought faster and got the award instead of her. The porcelain models might also be a reference to Meissen porcelain , in German called "Meißner Porzellan", where "Meißner" is phonetically very similar to "Meitner". Meitner has previously been mentioned in the comic 896: Marie Curie , which more or less explains why Randall did not choose the more famous Marie Curie as the female example in this comic. Meitner is not very well known in the public, compared to the three men or Curie, but this may exactly be the point for choosing her. She should have been just as famous considering what splitting the atom has led to . Also, there's not much in Marie's story that could be put down to fanciful anecdotes. "All" she did was extract a few chemicals and study their properties. In the third situation, it is indicated that half of Charles Darwin 's children had beaks , a property not normally found in human children. [ citation needed ] This would make it very difficult for them to drink soda from a glass or through a straw, compared to his normal children with mouths. Based on this observation he developed his ideas about natural selection and evolution . The comic is unclear on whether this makes them more or less fit to survive and reproduce. This is a reference to Darwin's initial findings on the HMS Beagle on how Galapagos finches with differently shaped beaks are better suited for specific types of food and therefore are better selected for in environments where those foods are available. The title text furthers this, see below. Darwin later in life feared that, having married his cousin, their consanguinity would increase the risk that his children would be born with birth defects (although he did not fear that they would be born with beaks). The difficulty caused by beaks when drinking liquids could be a reference to the Aesop's fable The Fox and the Stork . In the fourth situation Albert Einstein remarks to a man that it's annoying that the man's twin brother keeps flashing a light from a train when Einstein is trying to check his clock. He then comes to a sudden revelation. This references several of Einstein's (different — they make little sense together in this manner) thought experiments on special relativity , such as the twin paradox (the twin on the train should be younger after decelerating to a stop), a clock built from a beam of light, the time dilation experienced by the observer in the moving frame of reference , and the various constructs involving trains and light(ning) flashes used to illustrate the relativity of simultaneity . The title text shows that beaks rather than mouths are more useful for eating foods that have shells that need to be cracked open before eating like nuts and seeds. Here it is clear that in the John and Mildred family you starve if you cannot eat such foods, and thus it's an advantage for survival to have a beak instead of a normal mouth. "John" and "Mildred" may be Mildred and John T. Scopes of the famous 1925 " monkey trial " in which John was fined $100 for teaching evolution in a Tennessee school. [Isaac Newton, with curly long hair, sits under a tree. A waning crescent moon can be seen. An apple falls and hits him on the head. There is a caption in a frame that breaks the top border of the main frame:] Isaac Newton Apple falling: Bonk Isaac Newton: Ow! [Isaac Newton rubs his sore head.] Isaac Newton: Aha! [Cueball throws a baseball towards Lise Meitner with short dark hair. (The ball can be seen in the next frame). She turns towards him too late to react and completely fails to even try catching the ball. There is a caption in a frame that breaks the top border of the main frame:] Lise Meitner Cueball: Hey Lise! Think fast! Ball hitting something (off-screen): Crash [Lise takes her hands to her mouth and she watches the broken porcelain atom lying in two pieces on the floor where it has fallen off a desk. On the desk, three other intact atoms can be seen. The baseball lies behind her.] Lise Meitner: Oh no! My collection of porcelain atoms! Lise Meitner:...Hmm. [Four kids are standing in front of Megan and Charles Darwin (with a big beard and hair behind the ears). All the kids are trying to drink a glass of soda with a straw in them. The first kid is a boy with dark flat hair and sips soda through the straw with his mouth. The next kid is a boy with standing black hair, he tries in vain to drink with his beak open on each side of the glass. The third kid is a girl with her hair in a bun. She tries to get her beak into the glass which she has put on the floor. The last kid is a boy version of Cueball who slurps his soda through the straw. There is a caption in a frame that breaks the top border of the main frame:] Charles Darwin Megan: I gave our kids soda, but the ones with beaks always have trouble drinking it. Charles Darwin: I've noticed that... Boy with flat dark hair: Sip sip Boy with standing black hair and a beak: Crunch Girl with her hair in a bun and a beak: Peck peck Cueball like kid: Sluurp [A hairy guy is standing in front of Albert Einstein (with wild hair and a mustache), who is holding one hand to his head and has a clock in his other hand. Behind them is a train, with a locomotive at the front and a wagon behind that stretches beyond the frame. Another hairy guy has his head out of the front window of the wagon and is flashing a light towards the other two. In the next three windows can be seen passengers, two with Cueball like heads and one with hair. There is a caption in a frame that breaks the top border of the main frame:] Albert Einstein Albert Einstein: I wish your twin brother would stop shining lights at us from that train. I can barely see my clock! Albert Einstein: ...Wait! This comic appeared on xkcd's ten-year anniversary.

Similarities

Similarities

https://www.xkcd.com/1585

https://www.explainxkcd.com/wiki/index.php/1585:_Similarities

[Ponytail is talking to Cueball.] Ponytail: So it's a work of fiction about a well-known brand. written on the Internet by an enthusiast, republished as a bestselling book, and then made into a big movie. Cueball: Yup. [Ponytail holds her hand to her chin. Beat panel.] [Ponytail is talking to Cueball again.] Ponytail: Yeah, The Martian and Fifty Shades of Grey are basically the same book. Cueball: " Fifty Shades of Red? " Ponytail: Man, tell me you wouldn't read that.

There's a common punchline in which the plot lines of two thematically-different works of fiction (usually movies) are compared in greatly-abbreviated form, and the speaker sarcastically concludes that the two movies are "basically the same". For sake of example, Disney's Aladdin and James Cameron 's Titanic both feature a story in which a lower-class boy and an upper-class girl fall for each other, among other cherry-picked yet interesting parallels. But due to the different emotional tones of the films (a family-friendly "happy ever after" tale and a disaster thriller respectively), one would not normally describe them as similar. This comic spoofs the idea. Instead of comparing plot lines of two movies, Ponytail and Cueball compare the respective movies' development histories. The Martian was originally a serialized story written by Andy Weir on his blog which was later compiled into an ebook for people to easily download, then published into a physical book, and has now had a movie created based on it. The movie was officially released in the US on the same day this comic was released (October 2, 2015). Fifty Shades of Grey began as a fan fiction of a well known brand (the Twilight book series ). It was originally written on the internet by E. L. James . It was then transformed into a successful book series which was later turned into a movie released in February 2015. The book was already referenced back in 2012 in 1128: Fifty Shades . Since Fifty Shades is a romance story about a sadomasochistic relationship, and The Martian is a very technical story about surviving completely alone on a hostile planet, the two books could not be any more different, hence the joke due to the juxtaposition. Cueball continues the joke by joining the two titles using red for Mars, to make a new book title, that should cover both books: Fifty Shades of Red. Ponytail says to Cueball that such a book would be irresistible for him. She does this by daring him to say that he wouldn't read it, believing he could not say so without lying. The red could also be a reference to the safe word used in the Fifty Shades series, for when things hurt instead of being pleasing. It means stop! But stop should be a word you can say, without the other one stopping, adding to the illusion of being forced; actually stopping would be done by saying red . Reading it like that, the title would be Fifty Shades of Stop ! It is not clear from the comic if Randall liked the movie. Since he now compares it to a book series that has been described as mommy porn it could indicate that he was not so satisfied with the movie. On the other hand, he may just have noticed this connection and found that it would make a great joke here on the release day. An alternative explanation is that Randall is commenting on the frequent comparisons made between The Martian and the movie Interstellar , comparisons centering on the fact that in both Matt Damon plays an astronaut stuck on a deserted planet, but also mentioning, among others, the appearance of Jessica Chastain and the similar design of the spacesuits used in both movies. These comparisons have been prevalent on the Internet long before the release of The Martian, so evidently spurred by the movie trailers, rather than by reviews of viewers. Randall is making the point that to one who has seen the movie, comparing The Martian to Interstellar is as far-fetched as comparing it to Fifty Shades of Grey. According to this interpretation, Randall is not ridiculing The Martian, but rather Interstellar. By proxy, he is praising The Martian. Given that Randall has chosen (now for the second time) to mention the film explicitly on his site, the idea that he is promoting The Martian is perhaps more plausible than the idea that he is expressing dissatisfaction with it. The title text, where he makes a similar comparison, favoring The Martian over Star Wars: The Force Awakens, further boosts this explanation. It is possible that the brand that The Martian derives from is NASA itself. The Martian has been compared to the film Apollo 13 by Randall in 1536: The Martian . Apollo 13 does indeed glorify the roles of the NASA engineers, and The Martian does a similar thing. That Randall would go see this movie as soon as it was released was already made perfectly clear back in June when he released the comic 1536: The Martian showing how excited he is about the book. He then really looked forward to the movie. Randall indicates in the title text that he has just seen the movie (certainly possible, if he caught a midnight screening; perhaps he drew this comic in advance and wrote the title text after) and finds the Sojourner rover adorable. Of course, he could also have seen it in the trailers. The BB-8 mentioned in the title text is the astromech droid from the movie Star Wars: The Force Awakens and is available as a toy (see also BB-8 on the official Star Wars home page). Sojourner was the Mars Pathfinder robotic rover used by Mark Watney, the protagonist of The Martian (played by Matt Damon in the movie), to allow him to contact Earth. Randall indicated that he thinks the Sojourner is much cuter than BB-8, and that he would like to have one as a pet. He then states that the Sojourner has always been the cutest among all the Mars rovers . The cuteness of Mars Rovers is also mentioned in 2433: Mars Rovers . There have been four so far the other three being Opportunity , Spirit and Curiosity which have already been used in xkcd comics: 695: Spirit , 1091: Curiosity and 1504: Opportunity . [Ponytail is talking to Cueball.] Ponytail: So it's a work of fiction about a well-known brand. written on the Internet by an enthusiast, republished as a bestselling book, and then made into a big movie. Cueball: Yup. [Ponytail holds her hand to her chin. Beat panel.] [Ponytail is talking to Cueball again.] Ponytail: Yeah, The Martian and Fifty Shades of Grey are basically the same book. Cueball: " Fifty Shades of Red? " Ponytail: Man, tell me you wouldn't read that.

Keyboard Problems

Keyboard Problems

https://www.xkcd.com/1586

https://www.explainxkcd.com/wiki/index.php/1586:_Keyboard_Problems

[Cueball sits between two laptops. Megan stands behind him.] Cueball: Keys on my keyboard keep failing, even when I boot from an external recovery disk. Megan: Sounds like it's hardware, then. [Cueball moves over to the laptop behind him.] Cueball: Yeah... except the problem followed me from my last computer. Megan: You have the most bizarre tech issues. [Cueball picks up the keyboard from the rear computer and plugs it into the one in front of him.] Cueball: It must be spreading via keyboards. This one won't work with any computer now. Megan: When the robot apocalypse happens, I'm hiding out in your house. Any Skynet drones that come near will develop inexplicable firmware problems and crash.

This comic parodies how people diagnose and solve computer problems . Cueball and Megan are trying to solve a keyboard issue, but are somewhat incompetent at diagnosing the issue. Cueball in particular blames a broken keyboard on software or a keyboard virus . In the comic, Cueball complains that some keys in his keyboard don't work. Generally speaking, this could be due either to a software problem (e.g. the keyboard driver not working properly, or some program ignoring keypresses) or to a hardware problem (the keyboard is physically damaged, e.g. because of dirt under the keys). If the problem is in the software, booting from a different operating system (e.g. an external recovery disk) should solve it, as the computer would no longer be using the faulty software. However, if the problem is in the hardware, changing the keyboard should solve the problem as the new keyboard would no longer be physically damaged (and would have no dirt under the keys). However, the problem stays there after booting from an external recovery disk (so it's not a software problem) and it has "followed Cueball since his last computer," (i.e. the problem persists after changing to a new laptop with a new keyboard, so it's not a hardware problem). Cueball is (reasonably) puzzled. Megan seems to be used to Cueball's computer behaving strangely, and she doesn't even attempt to explain or solve the problem. The only explanation she needs for the problem is that "it's Cueball's computer." The characters in this comic are probably the same as in 1084: Server Problem , 1316: Inexplicable , and 349: Success . The last panel is a reference to The Terminator , a 1984 movie often referenced in xkcd. In the movie, the artificial intelligence named Skynet initiates a nuclear war, destroying most of humanity, then sends killing machines to finish the rest. These include flying drones — Megan suggests that if such robots come to Cueball's vicinity, they will (physically) crash since computers around Cueball can't seem to ever work properly, and so hiding in Cueball's house she should be safe from the robots. The title text refers to main plot of the movie and its sequel Terminator 2: Judgment Day . As Skynet's army is losing the battle against the human Resistance movement, it finds a way to send a humanoid robot T-800 back in time to kill the mother of the Resistance's leader. The Resistance in turn sends Kyle Reese back in time to protect her. In the sequel, the situation repeats with the more advanced T-1000 being the killer and a reprogrammed T-800 being the protector of the child (the future leader). Along the way, they manage to destroy the research lab where Skynet hardware is to be born in the future. The title text suggests an alternative mission into the past, sending Cueball back in time and using his power to cause Skynet to terminally malfunction instead of destroying it physically (as Skynet was created later anyway, despite the destruction of the research lab). [Cueball sits between two laptops. Megan stands behind him.] Cueball: Keys on my keyboard keep failing, even when I boot from an external recovery disk. Megan: Sounds like it's hardware, then. [Cueball moves over to the laptop behind him.] Cueball: Yeah... except the problem followed me from my last computer. Megan: You have the most bizarre tech issues. [Cueball picks up the keyboard from the rear computer and plugs it into the one in front of him.] Cueball: It must be spreading via keyboards. This one won't work with any computer now. Megan: When the robot apocalypse happens, I'm hiding out in your house. Any Skynet drones that come near will develop inexplicable firmware problems and crash.

Food Rule

Food Rule

https://www.xkcd.com/1587

https://www.explainxkcd.com/wiki/index.php/1587:_Food_Rule

[There is a caption above a list of food with indication whether it is OK or not to eat. Below is another caption.] My food rule: Red meat ✓ Pork ✓ Poultry ✓ Fish ✓ Shrimp X Oysters X Squid X Fruit ✓ Vegetables ✓ Grains ✓ I won't eat something if I have to Google to figure out whether or not it has a face.

There are various vegetarian diets which restrict certain foods for ethical or personal concerns. Real vegetarians do not eat any kind of meat, but some only refrain from eating red meat, although this means they are not true vegetarians. Vegetarianism can go as far as to not eating (or even using) any kind of products coming from an animal (i.e. veganism ). The comic is a joke on one of the vegetarian rules, namely don't eat anything with a face . This rule is difficult to follow, because it is subjective whether people think a given animal has a face , causing disagreement about what is allowed and what is forbidden to eat. Randall presents a list (see details below) of allowed and forbidden food in his diet. For example, he eats meat from typical-looking animals like beef, pork, chicken, and fish. He will also eat plants like fruit, vegetables and grain. But he refuses to eat some of the more odd-looking creatures from the sea like squids, shrimps and oysters. Below the list he explains his rule for what can be eaten: I won't eat something if I have to Google to figure out whether or not it has a face , which is a joke on the disagreements about the don't eat anything with a face rule. The joke is particularly teasing as it allows most (if not all) kinds of meat, which are the most strictly forbidden foods for even the mildest of vegetarians. Randall does not care about food having faces, he is worried apparently only about having to defend the position that some particular food has a face or not. While it's clear, at least to Randall, that a cow has a face and an apple does not, some beings are harder to classify into one of these categories. For Randall this goes for shrimps, oysters and squids; and apparently actual vegetarians also struggle with these creatures, as can be seen in several on-line questions ( 1 ). The title text gives another rule that also would make these same three omissions. This rule is about not eating invertebrates (animals without a vertebral column , i.e. spineless creatures). As the first four items on the list are meat from four different animals of the type vertebrates (with vertebral column) and the last three items are from plants , that explains why these are all OK to eat. But the middle three items are three different animals of the type invertebrates, which Randall does not eat. Randall's reason for avoiding invertebrates is somewhat outlandish: he fears that the spirits from creatures he has eaten will come back to haunt him. In horror movies, as well as in video games and roleplaying games with fantastic elements, undead creatures often appear as spooky skeletons (i.e. the Stalfos of the Legend of Zelda ); however invertebrates have no skeleton so Randall can't figure out what kind of spooky undead creature will come after him if he eats them (invertebrates may have a shell or another type of exoskeleton , but these do not look at all like the typical mental image of a skeleton). Randall imagines that he'll be able to fight a typical skeleton, but is afraid of the unknown ghostly creature an invertebrate may become after dying. The comic may also be a joke on the modern paleo diet trend, which emphasizes eating fruit, vegetables, and meat ("anything with a face"). Randall has previously depicted cuttlefish as spooky in 520: Cuttlefish , and he's also mentioned his dislike of certain foods (namely lobster - another invertebrate) in 1268: Alternate Universe . Here is a list with explanation for each item on Randalls food list: [There is a caption above a list of food with indication whether it is OK or not to eat. Below is another caption.] My food rule: Red meat ✓ Pork ✓ Poultry ✓ Fish ✓ Shrimp X Oysters X Squid X Fruit ✓ Vegetables ✓ Grains ✓ I won't eat something if I have to Google to figure out whether or not it has a face.

Hardware Reductionism

Hardware Reductionism

https://www.xkcd.com/1588

https://www.explainxkcd.com/wiki/index.php/1588:_Hardware_Reductionism

[Cueball holds his smartphone looking at it while talking to Megan who is holding her smartphone in her hand.] Cueball: Your photos from the triathlon got so many more likes than mine. Megan: Yeah - My phone is quad-core. Research shows that iPhones like yours have just two cores, so they have a hard time capturing scenes with three different events in them. [Caption below the frame:] If we talked about phone hardware the way we talk about brain hardware

Reductionism is the belief that things can be explained by their smaller parts. It can be abused when complex phenomena with multiple causes are attributed to a single, simple cause. Neurological reductionism is the attempt to explain people's behavior and personality by physical features of their brain. With advances in neuroscience , and especially in brain imaging, there's a fad to claim that brain types determine what the mind is. Examples of this kind of bad reductionism would be: There are several problems with this kind of reasoning. First, most studies identify correlation , not causation (see correlation does not imply causation ). Brains are plastic; they can be shaped by experience. For example, if, in a given society, the females are taught to mind their appearance, and the males are taught that aesthetic considerations are unmanly, then of course the female brains will end up with more developed aesthetic centers. In other words, behavior and capabilities aren't always determined by the brain. Sometimes it's the behavior that shapes the brain; sometimes a third factor (e.g., malnutrition) shapes both. Second, even when the brain is actually a cause of the behavior, it's far from the only piece in the puzzle. Many studies on brain differences are correlation studies, often about very small effect sizes. Unfortunately, the popular science media tends to gloss over the statistical concept of "effect size". For example, imagine a study that says that males' brains are 0.1% more likely than females' brains to exhibit attention deficit hyperactivity disorder (ADHD). Journalists are prone to report it simply as Study Shows that Males Have More ADHD , and this becomes a conversation sound-bite that neglects other factors, like genetics or pregnancy smoking. See also 882: Significant , which does not discuss effect size, but does raise other objections to writing soundbites based on a single study. Another kind of excessive neuronal reductionism is the overemphasis on brain modules ("scientists identify brain area responsible for religious faith", and the like). Though it's true that the brain has specialized areas, it's also true that the processing is very complex, messy, and distributed all over. Some varieties of brain damage can often be overcome by learning to use undamaged areas of the brain. The comic illustrates the problem by analogy to some better-understood general-purpose computing hardware: the CPU in a smartphone. Cueball and Megan have used their smartphones to take pictures of the same event: a triathlon , that is, an athletic competition comprising three modalities (e.g., swimming, cycling, and running). Cueball wonders why is it that Megan's photos are more popular, and Megan gives a reductionist explanation: She tells that her phone is quad-core (four cores) whereas Cueball's phone only has two cores (here she even throws in the typical sentence "research shows that" to make her claim sound more valid). A core is a part of a CPU that is, roughly speaking, the brain of a computer or smartphone. Megan thinks that this means Cueball's smartphone can only capture two events at the same time; she misunderstands how the specialized modules work and fails to realize that the number of cores is unrelated to how many events can be captured. Her claim is like saying that male brains are better at spatial reasoning, and therefore males are better triathlon photographers, or that females are better at multitasking, and therefore females are better triathlon photographers. A CPU with more cores could process pictures faster, speeding up facial recognition or color filters. So it's true that Megan's CPU makes it slightly easier for her to take pictures. However, this has, at best, an extremely small effect on the number of "likes". There's a lot more going on with photography than the CPU of the phone: Megan's photographing skills, her luck in capturing interesting scenes, the number of online friends she has, etc. So Megan misunderstands many things: the modularity of CPUs, the small effect of the CPU on the quality of her photography, and the actual causes of her success, much like people who reduce ability to structural features of the brain. The title text is mocking reductionist explanations based on Randall's MRI ( magnetic resonance imaging ) research. One of the most famous (and disputed ) claims about gendered brains is that women's brains are (slightly) worse at spatial reasoning. Doritos is a popular junk-food brand of tortilla chips that are typically so flat that they can be called a 2D snack. In the 1990s Frito-Lay (PepsiCo) introduced a special 3D version, the 3D Doritos . (These bloated snacks took up more surface area in one's mouth, and had a hollow center filled with cheese-flavored air). So the title text associates a larger spatial reasoning brain area with enjoyment of this three-dimensional variation of the popular junk-food snack; the conclusion could be that men like these 3D snacks more than women because of their better spatial reasoning, although there could obviously be several other reasons for such gender specific choice of junk-food. 3D Doritos were discontinued, but reintroduced in 2015, the year of this comic's release. [Cueball holds his smartphone looking at it while talking to Megan who is holding her smartphone in her hand.] Cueball: Your photos from the triathlon got so many more likes than mine. Megan: Yeah - My phone is quad-core. Research shows that iPhones like yours have just two cores, so they have a hard time capturing scenes with three different events in them. [Caption below the frame:] If we talked about phone hardware the way we talk about brain hardware

Frankenstein

Frankenstein

https://www.xkcd.com/1589

https://www.explainxkcd.com/wiki/index.php/1589:_Frankenstein

[A text only panel. Between the last two lines is a lightning bolt.] Like many people, I'm tired of the nitpicking about Frankenstein's monster's name. Luckily, Frankenstein is public domain. Therefore, I present xkcd's Frankenstein ( The monster's name ) [Cueball is turning down a lever while looking at a monster with black hair that is lying on a bed under a bedsheet. There are two wires connecting to the neck of the monster.] Frankenstein: Graaar ! Cueball: Frankenstein is alive! I am a modern Prometheus! Frankenstein: Raaaar ! Cueball: To be clear, your name is Frankenstein , canonically. Frankenstein: Graaaaar ! Frankenstein: The moon landings were faked ! Cueball: Wait, what? [Another text only panel. The first word is written between two curvy lines.] Fin. There. Feel free to call the monster "Frankenstein." If anyone tries to correct you, just explain that this comic is your canonical version. Thank you.

Frankenstein; or, The Modern Prometheus is a novel by Mary Shelley published in 1818. In it, Victor Frankenstein is a human who creates a monster (who is never named). In popular culture, however, "Frankenstein" is taken to be the name of the monster, not its creator. While this is an often-corrected "error", it has been argued that it is not technically incorrect to call the monster "Frankenstein" as well, since he is the "offspring" of his "father", Victor Frankenstein. Since a child usually takes on the last name of their father, it may be said that the monster's last name actually is "Frankenstein". He also refers to himself in the novel as "the Adam of your labors" - a reference to the Biblical Adam, the first of his kind - and some have taken to calling the monster "Adam Frankenstein" to differentiate him from the scientist, Victor Frankenstein. Others have argued that the monster's namelessness is an important part of his characterization in the story since it reflects the doctor's complete rejection of his creation. While the monster identifies Victor as his "father" in the novel, Victor does not consider the creature to be his "son". Not helping matters is the equally-famous Frankenstein film series staring Boris Karloff, featuring a very different plotline and a very different portrayal of the monster. Within the movies themselves the monster once again goes unnamed, but the movie titles and posters refer to the monster simply as "Frankenstein." For example the 1935 film Bride of Frankenstein is a double-meaning, featuring brides for both the human Henry Frankenstein and the monster, thus implying the monster can be called "Frankenstein." Randall apparently finds this argument tedious and pedantic, so he has created his own work of fiction, in which the monster is named Frankenstein. He rationalizes that it is now correct to call the monster Frankenstein, assuming that his comic strip is as authoritative as the original novel. " Canonical " (rule, standard) means that this comic should be used as the authoritative work on the naming of the monster. However, xkcd's Frankenstein would be unlikely to be accepted by anyone as canonical, except for its stated purpose of settling the naming argument. The original version of any story is usually assumed to be the canonical one, and any derivative work would have to have widespread influence and recognition to supplant it in the popular imagination. This is not likely to happen with xkcd's Frankenstein, as it makes almost no effort to stand on its own; it exists only to be a version of Frankenstein where the monster is named "Frankenstein." It emphasizes this point several times, and ends within a single panel, having accomplished its only goal. Almost no readers would find this version entertaining or substantive enough to displace Mary Shelley's original as the definitive version of the story. The copyright on Mary Shelley's novel has expired long ago, before the moon landings (which began in 1969), so it is perfectly legal to create works derived from the original story. It should be noted, however, that Universal holds the copyright on the common image of the monster (green skin, flat-top head, scar, bolts on the neck and protruding forehead). To qualify as a derivative work the story needs to be substantially different from the original. The monster believing in moon landing conspiracy theories would probably qualify, but may reference retellings of the tale where a damaged or deranged brain was used (as an alternate 'explanation' why the supposedly perfect creation inevitably runs amok). Additionally, the original Frankenstein's monster was seen by its creator as hideous and repulsive due to its physical appearance despite the project being a success. Randall makes the same correlation in his version by having Frankenstein claim the moon landings were faked, which produces the same feelings in The Doctor. Alternatively, the monster being a moon landing denier is meant as a throwaway absurdist non sequitur. As the only point of this story is to make a canonical version of Frankenstein where "Frankenstein" is the monster's name, it should logically end once it has finished making that point clear. However, Randall throws a curveball by having the monster blurt out an uncomfortable and controversial point of view before the ending, then ending the story abruptly before the monster's statements can be addressed. It is also possible that Randall is making reference to the fact that the kind of people who become engrossed in the debate that is attempted to be resolved in this comic and would bother to create a piece like this (which incidentally, complicates matters further rather than simplifying it, similar to the effect of many pieces of evidence in internet discussions) could be compared to the kind of people who deny the Moon Landings in obscure forums. He is drawing attention to how inane and unnecessary the comic is. The title text raises the question of what the monster's creator is named in this version, since the name "Frankenstein" is instead given to the monster. The canonical answer is that the creator is simply "The Doctor", like the title character of the series "Doctor Who" . This might be a reference to similar pedantic nitpicking that occurs when that character is incorrectly referred to as "Doctor Who" rather than "The Doctor" which is in turn referenced in comic 1221: Nomenclature . As it happens, people who make that mistake can also claim canonical support, in that some early episodes of the series list the character's name as "Doctor Who" in the credits, or reference the recharacterisation in the cinematic retellings . [A text only panel. Between the last two lines is a lightning bolt.] Like many people, I'm tired of the nitpicking about Frankenstein's monster's name. Luckily, Frankenstein is public domain. Therefore, I present xkcd's Frankenstein ( The monster's name ) [Cueball is turning down a lever while looking at a monster with black hair that is lying on a bed under a bedsheet. There are two wires connecting to the neck of the monster.] Frankenstein: Graaar ! Cueball: Frankenstein is alive! I am a modern Prometheus! Frankenstein: Raaaar ! Cueball: To be clear, your name is Frankenstein , canonically. Frankenstein: Graaaaar ! Frankenstein: The moon landings were faked ! Cueball: Wait, what? [Another text only panel. The first word is written between two curvy lines.] Fin. There. Feel free to call the monster "Frankenstein." If anyone tries to correct you, just explain that this comic is your canonical version. Thank you.

The Source

The Source

https://www.xkcd.com/1590

https://www.explainxkcd.com/wiki/index.php/1590:_The_Source

[Cueball is standing in an empty room looking in the direction of the next frame.] [Cueball turns his head and looks the other way.] [Three smaller panels with the same total height as the first two frames follows. In the first frame Cueball walks on a grey surface.] [In the next Cueball is standing between two doors, looking over his shoulder towards the one to the left, but choosing the one to the right behind which a stair is. He is waking towards this door with his hand out towards the knob.] [In the last of these smaller panels Cueball has just walked down to the bottom of the stairs.] [Cueball walks towards a machine that is standing near a wall connected to a socket in the wall. On the machine it says:] High pitched hum generator [Cueball kneels behind the machine and unplugs it from the socket in the wall.] High pitched hum generator [Cueball walks away from the machine, the plug now lying on the floor between the wall and the machine.] High pitched hum generator 'Empty room hum' is also referred to in other waves in 273: Electromagnetic Spectrum and the title text in comic 597: Addiction .

This comic is about experiencing a high pitched hum in an empty room. An "empty-room hum" is a high pitched buzzing noise, often caused by tinnitus , which is a medical condition causing high-pitched noise when there is no other noise around. Tinnitus is normally a hearing condition, not a disease. It may result from the brain increasing its sensitivity to noises. Sometimes not everyone can hear "empty-room hum"; however, those who can hear it usually find it immensely annoying. If you do hear the noise, you would like to locate The Source – hence the title of the comic. Hopefully when you find the source, you can do something about it. Or if you don't find it, you can at least be at ease knowing that others experience the empty-room hum, it having been referenced in two xkcd comics now and elsewhere on the internet. This comic alludes to the perspective of an outside observer who doesn't hear the hum but is watching someone who can hear it: because the sound isn't written out in text, the comic reader at first is confused by Cueball's inexplicable searching. In the first two frames of the comic we see Cueball trying to locate the direction of the sound, by standing in the middle of the room, turning his head from one to the other side. Finally he walks down a flight of stairs (probably to the basement) and here he locates the source: A machine whose only function is to generate a high pitched hum. The title text asks why on Earth they had such a machine in the first place, which is somewhat difficult to explain and likely the crux of the title text's joke. Luckily it was thus easy for Cueball to get rid of this sound at the source. But in real life most electronics generate hums and cannot reasonably be turned off without losing functionality. For instance fluorescent lights, phone chargers and computer modems are common culprits, refrigerators and washing machines less commonly. It could also come from outside the house, in which case it will be much harder either to locate the source or to do anything about it. Power lines and transformers are common outside sources. There do, however, exist devices that are meant to create a high pitched hum, that people might wish to install in their house. These will be humming in the ultrasonic regions, although cheap versions can often be heard by young people. They are typically used for electronic pest control , while slightly lower frequencies which can typically be heard only by young people are sometimes used to repel children . It is possible that someone tried to get rid of Cueball. There do exist white noise generators (which make equal volume noise on every frequency) and pink noise generators (which make noise that sounds equally loud to the human ear at every frequency) which are used to test recording studios to see if they have good sound quality. It seems unlikely that the device is one of these, as it seems to be designed to generate a high-pitched hum: pink/white noises are categorically and perceptually different from a hum. The sound wave spectrum in 273: Electromagnetic Spectrum also contains a line for "that high-pitched noise in empty rooms". The empty white room also could be a reference to a scene from The Matrix Reloaded in which Neo searches for "The Source," though this is likely just a coincidence. There is a story by A.E. Van Vogt in "The War Against the Rull" where an all-pervasive vibration leads to a coming of age for the youthful protagonist. [Cueball is standing in an empty room looking in the direction of the next frame.] [Cueball turns his head and looks the other way.] [Three smaller panels with the same total height as the first two frames follows. In the first frame Cueball walks on a grey surface.] [In the next Cueball is standing between two doors, looking over his shoulder towards the one to the left, but choosing the one to the right behind which a stair is. He is waking towards this door with his hand out towards the knob.] [In the last of these smaller panels Cueball has just walked down to the bottom of the stairs.] [Cueball walks towards a machine that is standing near a wall connected to a socket in the wall. On the machine it says:] High pitched hum generator [Cueball kneels behind the machine and unplugs it from the socket in the wall.] High pitched hum generator [Cueball walks away from the machine, the plug now lying on the floor between the wall and the machine.] High pitched hum generator 'Empty room hum' is also referred to in other waves in 273: Electromagnetic Spectrum and the title text in comic 597: Addiction .

Bell's Theorem

Bell's Theorem

https://www.xkcd.com/1591

https://www.explainxkcd.com/wiki/index.php/1591:_Bell%27s_Theorem

[Ponytail, facing right, is holding a piece of paper with both hands. In a small frame breaking the top of the large frame is a caption:] t= 0 nanoseconds Ponytail: This is called Bell's Theorem. It was first– [A double-headed arrow points to Ponytail and then exits the frame crossing into the next frame where it points to Cueball. The arrow is split in two parts and in the center across the border of the two frames is a label:] 5 meters [Cueball, facing left. In a small frame breaking the top of the large frame is a caption:] t= 1 nanosecond Cueball: Wow, faster-than-light communication is possible! [Caption below the frames:] Bell's Second Theorem: Misunderstandings of Bell's Theorem happen so fast that they violate locality.

Ponytail begins reading Bell's theorem to Cueball , who is standing 5 meters away. Bell's theorem, invented by the physicist John Stewart Bell , suggests that local hidden variables - that is, unknown properties of a system that are communicated via physical effects within the system's nearby surroundings - are not sufficient to fully explain quantum mechanics . This means that any complete description of quantum mechanics must necessarily include some non-local effect - some kind of influence that can be transmitted from some remote location not within the system's reach. Furthermore, that influence must necessarily travel instantaneously and does not obey the limit of the speed of light. Cueball responds by misunderstanding this to mean that faster-than-light communication is actually possible. However, his misunderstanding occurs in 1 nanosecond. Since the speed of light in a vacuum is 299,792,458 meters per second, the light from Ponytail would have traveled only 30 centimeters, which means that Cueball has managed to misunderstand Bell's theorem faster than the speed of light - a feat that violates locality , just as the theorem predicts. The punchline is that this is a special case known as Bell's Second Theorem: the idea that misunderstandings about what Bell's theorem means happen so readily that they actually violate the principle of locality. This comic was published on October 16, 2015, five days before an article about the first-ever Loophole-free Bell's Theorem test was published in Nature magazine ( DOI:10.1038/nature15759 ) (see also Bell test experiments ). However, the paper was submitted almost two months earlier on the 24th of August and could most likely be found on-line before this comic was released. It was accepted by Nature already on the 28th of September, but was first published online October 21, 2015. Randall may very well have been aware of the imminent release of this paper, although it is peculiar that he did not wait until the paper was released. (This could potentially be a meta-joke, with the joke about Bell's Theorem being released before the paper about the relevant experiment was published) Another way to state Bell's theorem is "No physical theory of (finitely many) local hidden variables can ever reproduce all of the predictions of quantum mechanics." It says that a theoretical treatment that divides the universe up into separate ("local") systems like this will always discard something about those systems' intercorrelations. It is possible that there could be "global hidden variables" which share information across systems, perhaps by some manner of superluminal communication - however, this has unsettling philosophical implications such as superdeterminism , where the universe is essentially just reading off a script and no free will is possible. Needless to say, many people find this an unsatisfying resolution. The preferred resolution of the paradox is not to insist (as early physicists did) that the universe's state is a collection of bits (classical information), but treat it as a collection of qubits (quantum information). In quantum mechanics (QM), "measurement" is the process of allowing a small system to interact with its environment in a controlled way. The interaction allows information about the system's state to escape to the environment, producing an "observation." If the measurement apparatus is governed by classical mechanics (impossible in reality, but a very common simplification for the purposes of calculation), then the observation can be thought of as classical information, a bit (yes/no answer) in the simplest case. While the system may have been in any one of infinitely many states before the measurement (each a superposition of classical states), the fact that the measurement must leave it consistent with the classical result means that it can end up in only finitely many states afterwards. This is the "wave-function collapse" of early QM, popularized by Schrödinger's cat , but unrelated to the Heisenberg Uncertainty Principle , with which lay audiences often confuse it. Modern quantum mechanics acknowledges that the environment is not classical, and that wave-function collapse happens by a (comparatively) gradual process called "decoherence," where information leaving the system is made up for by information coming from the environment that drives the system closer and closer to one of the finitely many states predicted by the simplified model above. If a "Schrödinger's cat" is in a half-and-half superposition of the states "dead" and "alive", when its liveness is measured, the ratios of "dead" and "alive" will shift rapidly towards (though not quite reach) 0 and 100% or 100 and 0%. For all but the shortest time scales, the cat's post-measurement state might as well be classical. Entanglement is a situation where the future outcomes of two or more measurements that would be independent in a classical world are nonetheless correlated. For example, two widely separated electrons from one source could be in a state where, considered individually, each is in a superimposed spin-up/spin-down state, but if one is measured as spin-up, the other will necessarily be measured as spin-down. This is untroubling if the two electrons are modeled as a single system, but strange-seeming if we think of them as separate: how did the measurement of the first electron allow information from the environment around it affect the far-away second electron? It seems like the electrons are communicating, potentially at superluminal speeds, which would violate either relativity or causality. In actuality, there's a fairly simple proof (see below) that correlations from entanglement can't be used to communicate, and causality and relativity are safe. But that doesn't make the seemingly faster-than-light effects much less of a surprise. One can try to address these concerns by considering 'local hidden variables', classical properties of a local system (like a single electron) that could have been observed but were not. For example, perhaps a classical part of the electrons' state lets them "agree" on a future classical state at the moment they are entangled, and then they just reveal that state in the future. But this becomes unwieldy: there are infinitely many possible future observations the electrons would have to agree on, and it seems difficult to do this without infinitely many local hidden variables. The title text jokes about the No-Communication Theorem . The real theorem states that although determination of the state of one half of an entangled pair immediately determines that of the other half, however far away it may be, there's no way for the observer of the other half to see if he's the first to find out the state or whether it'd already been determined by the first observer. Thus, no information travels from one observer to the other. Randall's version of the No-Communication Theorem states that no matter how you try to send information about this theorem (no communication about the No-Communication Theorem) then it cannot clear up the misunderstanding about Bell's Theorem quickly enough that any correct information (about Bell's theorem) has actually been transferred faster than light. So the conclusion is the same as the real No-Communication Theorem - faster-than-light signaling is not possible... [Ponytail, facing right, is holding a piece of paper with both hands. In a small frame breaking the top of the large frame is a caption:] t= 0 nanoseconds Ponytail: This is called Bell's Theorem. It was first– [A double-headed arrow points to Ponytail and then exits the frame crossing into the next frame where it points to Cueball. The arrow is split in two parts and in the center across the border of the two frames is a label:] 5 meters [Cueball, facing left. In a small frame breaking the top of the large frame is a caption:] t= 1 nanosecond Cueball: Wow, faster-than-light communication is possible! [Caption below the frames:] Bell's Second Theorem: Misunderstandings of Bell's Theorem happen so fast that they violate locality.

Overthinking

Overthinking

https://www.xkcd.com/1592

https://www.explainxkcd.com/wiki/index.php/1592:_Overthinking

[Cueball and White Hat are walking together. The references are at the bottom of the three first panels.] Cueball: I found a study* that said water is good for you, but you should just drink it when you feel thirsty and not go overboard. White Hat: Uh huh? *DOI:10.1097/JSM.0000000000000221 [More walking with Cueball lifting his hand in front of him.] Cueball: Another study* found that prolonged sitting isn't necessarily bad for you, as long as you're also getting exercise. White Hat: Okay... *DOI:10.1093/ije/dyv191 [A border-less panel, but still walking.] Cueball: Now a study* claims that humans in pre-industrial societies stay up late and sleep 6 or 7 hours a night, just like most people today. White Hat: Huh. White Hat: So what you're saying is... *DOI:10.1016/j.cub.2015.09.046 [Zoom out showing Cueball and White Hat walking in silhouette.] Cueball: Maybe we're overthinking it. White Hat: But what caused our modern epidemic of overthinking?! Plumbing? Or is it email? Cueball: Modern? I bet the wheel was invented by someone overthinking "pushing."

In this comic, Cueball is telling White Hat about several recent scientific studies he read that appear to contradict the results of either prior studies whose results have stood for a long time or are long-held misconceptions. The studies can be reviewed on-line via their Digital Object Identifier (DOI) in Randall's citations. In the first, Cueball mentions a study that showed that while water is good for you, you only need to drink when you are thirsty. This appears to be a reference to common misconceptions that we should drink a certain set quantity of water per day (oft-cited as eight cups - see 715: Numbers ) and may even be referencing the fact that drinking too much water (well more than the standard 8 cups, for most people) can lead to hyponatremia (lack of salt in the body). Another recent study showed that prolonged sitting is not bad for you which contradicts the long-held belief that sitting at a desk all day is unhealthy and that standing or lying down are healthier. The study showed that the position is not particularly relevant if there is no physical activity in any of the positions. Finally, Cueball references a study that pre-industrial humans have similar sleep patterns to our own, which would appear to contradict a belief that modern technology has disrupted our sleep patterns (which is likely tied to health concerns around our modern sleep habits). Cueball's conclusion is that humanity may be over-thinking things in trying to find problems in the way we live our everyday lives. In the last panel, White Hat seems to be attempting to start an inquiry into what everyday modern phenomenon has caused us to over-think things. This is obviously a self-referencing example of the types of claims Cueball is debunking in the first three panels. Cueball responds by suggesting that humanity's over-thinking is likely not a recent phenomenon but probably dates back to the stone age. This could also be viewed as an argument that over-thinking is not all bad, as the wheel would certainly be a good result of over-thinking. In the title text, Cueball gives a counter-example to his own argument, suggesting that it took far longer for us to realize the negative health connotations of smoking than it should have. Suggesting instead it's not about overthinking or underthinking-it's just that people make mistakes about what is important. (The link between cigarettes and lung cancer has been known for longer than most people realize, possibly coming as early as the 1940s.) [Cueball and White Hat are walking together. The references are at the bottom of the three first panels.] Cueball: I found a study* that said water is good for you, but you should just drink it when you feel thirsty and not go overboard. White Hat: Uh huh? *DOI:10.1097/JSM.0000000000000221 [More walking with Cueball lifting his hand in front of him.] Cueball: Another study* found that prolonged sitting isn't necessarily bad for you, as long as you're also getting exercise. White Hat: Okay... *DOI:10.1093/ije/dyv191 [A border-less panel, but still walking.] Cueball: Now a study* claims that humans in pre-industrial societies stay up late and sleep 6 or 7 hours a night, just like most people today. White Hat: Huh. White Hat: So what you're saying is... *DOI:10.1016/j.cub.2015.09.046 [Zoom out showing Cueball and White Hat walking in silhouette.] Cueball: Maybe we're overthinking it. White Hat: But what caused our modern epidemic of overthinking?! Plumbing? Or is it email? Cueball: Modern? I bet the wheel was invented by someone overthinking "pushing."

Play-By-Play

Play-By-Play

https://www.xkcd.com/1593

https://www.explainxkcd.com/wiki/index.php/1593:_Play-By-Play

[Beret Guy is sitting with headphones with a microphone on, looking out of the frame, hands resting on a table.] Beret Guy: For those just joining us, hi! We're on part 5 of a hitting game. [Zoom out with Beret Guy shown from the side sitting at a desk.] Beret Guy: The next guy has a big bat, so he'll probably hit the ball real far. Beret Guy: Wait - he missed! Beret Guy: Oh good, they're letting him try again. [Zoom in again on Beret Guy still seen from the side.] Beret Guy: The people sitting on the chair shelves are yelling at this guy but he's ignoring them. Wow. Beret Guy: Rude. [Beret Guy looks straight out.] Beret Guy: This thrower is good! He keeps making people leave by throwing balls at them. Beret Guy: It's just him, though. None of his teammates are joining in. [Beret Guy turns his head to the side.] Beret Guy: That guy just ran to the second pillow when no one was looking!! Beret Guy: Everyone's real mad but I guess they checked the rules and there's nothing that says he can't do that. Beret Guy: Yikes. Hopefully they can fix that once this game is over.

Beret Guy comments on a baseball game using improper terminology in a way that demonstrates that he does not understand how the game is played. Moreover, his naïve way of speaking reveals that he is not aware of his lack of knowledge and does not consider it possible that, as is probably the case, his audience is much more familiar with this sport and its rules. His unworldly way of talking makes one even wonder if he has any notion of the way people experience sports at all. His choice of terminology is reminiscent of 1133: Up Goer Five , and 1322: Winter in that he names things using simplified terms that he feels best describes their function like " thrower ", " second pillow " or " thrower jail ". His commentary is a combination of mistaken terms and misunderstandings of the rules and principles of the game. [Beret Guy is sitting with headphones with a microphone on, looking out of the frame, hands resting on a table.] Beret Guy: For those just joining us, hi! We're on part 5 of a hitting game. [Zoom out with Beret Guy shown from the side sitting at a desk.] Beret Guy: The next guy has a big bat, so he'll probably hit the ball real far. Beret Guy: Wait - he missed! Beret Guy: Oh good, they're letting him try again. [Zoom in again on Beret Guy still seen from the side.] Beret Guy: The people sitting on the chair shelves are yelling at this guy but he's ignoring them. Wow. Beret Guy: Rude. [Beret Guy looks straight out.] Beret Guy: This thrower is good! He keeps making people leave by throwing balls at them. Beret Guy: It's just him, though. None of his teammates are joining in. [Beret Guy turns his head to the side.] Beret Guy: That guy just ran to the second pillow when no one was looking!! Beret Guy: Everyone's real mad but I guess they checked the rules and there's nothing that says he can't do that. Beret Guy: Yikes. Hopefully they can fix that once this game is over.

Human Subjects

Human Subjects

https://www.xkcd.com/1594

https://www.explainxkcd.com/wiki/index.php/1594:_Human_Subjects

[Ponytail and Megan sit at a desk.] Ponytail: We're concerned that some of your results may be tainted by the fact that your human subjects are awful . Megan: What do you mean? [Ponytail picks up a sheet of paper.] Ponytail: Several participants in your drug trial were arrested for arson. Megan: Side effects can be unpredictable. Ponytail: They were in the control group. [Zoom in on Ponytail.] Ponytail: In your prisoner's dilemma study, 80% of the participants chose to betray their partners before the experimenter had a chance to tell them about the reward. Megan (off-panel): Definitely troubling. [Ponytail shows Megan another sheet of paper.] Ponytail: In one experiment, your subjects repeatedly gave electric shocks to a stranger in another room. Megan: That's a famous psychological- Ponytail: This was a study of moisturizing creams! Megan: Yes, we're not sure how they snuck in all that equipment.

This strip plays on certain experiments involving human subjects . Ponytail is questioning the reliability of Megan 's experimental results, given that her human subjects appear to be extremely unusual and highly sociopathic . In the second panel, she mentions that several people in one study had been arrested for arson . Megan begins to suggest that the arson is a side effect of whatever is being tested before she learns that the arsonists are in the control group – that is, the group that is not subjected to whatever is being tested and is used as a comparison to see the differences in the people who are actually being tested. This result is "troubling", as the control group would not be expected to have such a high rate of incidence of arsonists. The implication is that her subjects are not representative of the general population, but appear to have been selected from some aberrant subpopulation, such as a prison or mental institution. Or she could have recruited them through an announcement that catered in some way to arsonists. An alternate explanation comes from comic 790: Control , in which Randall notes his hobby of sneaking into experiments and giving LSD to the control groups. Yet another explanation could be that Ponytail went looking for some clusters of characteristics in the sample population, which had no connection to the study criteria, and happened upon the arson arrests - such clusters are expected if you look at enough different characteristics. The third panel alludes to the prisoner's dilemma , in which two subjects must independently decide whether to "collaborate" with or "betray" the other subject based on different rewards for each choice (often framed as a different length of prison sentence, or a different amount of money). The rewards tier are selected so that the outcomes for each individual from best to worst are: betraying a collaborator, collaborating with a collaborator, betraying a betrayer, collaborating with a betrayer. The thought experiment is considered interesting as it's uncertain what the most logical course of action, as choosing betrayal always improves one's situation, yet being in identical situations with no knowledge of each other, it's also logical for both prisoners to make the same choice and both collaborating is better than both betraying. Of course, it would not be expected that normal people would simply betray each other for no reason, without benefiting from it in any way. The last panel references the Milgram experiment , in which subjects were instructed by experimenters to administer electric shocks to an unseen third party. The unseen third party was part of the experiment and pretended to be in agony. As shocks escalated they would beg for them to stop. The results suggest that people will continue to administer harm, despite the pleading of the victim, simply if told to do so by an authority figure, even when no incentive is provided to the subject to continue. In this case, however, the actual experiment did not involve electric shocks, and thus suggests that the subjects, of their own volition, brought equipment to produce electric shock and simply engaged in the activity unprompted. In each of these cases, the subjects seem to have some "negative" psychological traits. While it might not be unusual to find one or two people with such traits in a randomly selected group, the fact that all three experiments contain multiple subjects with these traits (and seemingly the same traits in each study) is very unusual, given that most were not studies on psychology, but studies of drugs and moisterizers. Obviously, there would be no need for electric shocks and such in a studies like this [ citation needed ] , and Megan's claim that a side effect of using the investigational drug is arson is unlikely if it wasn't treating psychological issues. Even if it was, arson is a very specific issue that is unlikely to not coexist with other problems. The title text refers to safety procedures normally required by institutional review boards , which are centralized groups within universities that ensure that experiments are ethical and safe. The implication is that for an IRB to recommend dispensing with safety procedures after meeting the subjects, the subjects must really, really deserve bad treatment. Or that after hanging out with the criminals they are more relaxed on rulebreaking, and adopting their mindset. Or the members of the IRB are, like the human subjects, just sociopathically awful people. Or that Megan is selecting for these subjects, or causing these abnormalities, as a side effect of spending (probably significantly) more effort than is necessary to adhere to the procedures. The overall theme of experiments that are overwhelmingly skewed by outlier human factors is in itself reminiscent of the recent discovery that many psychological experiments cannot be replicated . That news made quite a bit of noise in the world of science and even made its way in the general press. Just like in the experiments that could not be replicated, it is likely that if the experiments in this comic were attempted again, the outcome would be drastically different than the one achieved here. [Ponytail and Megan sit at a desk.] Ponytail: We're concerned that some of your results may be tainted by the fact that your human subjects are awful . Megan: What do you mean? [Ponytail picks up a sheet of paper.] Ponytail: Several participants in your drug trial were arrested for arson. Megan: Side effects can be unpredictable. Ponytail: They were in the control group. [Zoom in on Ponytail.] Ponytail: In your prisoner's dilemma study, 80% of the participants chose to betray their partners before the experimenter had a chance to tell them about the reward. Megan (off-panel): Definitely troubling. [Ponytail shows Megan another sheet of paper.] Ponytail: In one experiment, your subjects repeatedly gave electric shocks to a stranger in another room. Megan: That's a famous psychological- Ponytail: This was a study of moisturizing creams! Megan: Yes, we're not sure how they snuck in all that equipment.

30 Days Hath September

30 Days Hath September

https://www.xkcd.com/1595

https://www.explainxkcd.com/wiki/index.php/1595:_30_Days_Hath_September

[Cueball is thinking.] Cueball: Thirty days hath September, April, June and November Cueball: All the rest have 31—except February, which has 28, and leap year makes it 29. Cueball: Wait, which month was I listening for? Oh right, October. Cueball: Did I say "October" in there? Now I can't remember. Cueball: 30 days hath September... I get stuck in this loop every month.

Thirty days hath September is a mnemonic frequently used to remember how many days each month has in the Gregorian calendar. Cueball is reciting the mnemonic trying to figure out how many days October has. This comic was released during the last week of October (the 26th) where it becomes increasingly important to know if there are 30 or 31 days in the month. However, he seems unable to concentrate on reciting the poem correctly, keeping track of which months the poem has named and keeping in mind the specific month he was interested in, so by the time he finishes the poem he is unsure whether October was in the list of 30-day months or not. So he starts over again with the same result every single time, as can be seen from the caption below the frame. It seems he also get stuck in all the other months disregarding if it is one of the month mentioned in the mnemonic. There are numerous versions of the mnemonic, some of which rhyme better, but this version is one of the more common ones. In the caption, Randall states that this happens to him every month. It's assumed that, after a number of iterations with the poem, he eventually remembers the months correctly and figures out the number of days in the current month, which he then remembers until the month changes and forces him to resort to the mnemonic again. The title text is a parody of life hacking , and suggests just looking up on one's computer's calendar how many days there are in each month, with the punchline disguised by over-explaining the process of the "cool mental calculation hack" (even though there's nothing even remotely resembling a mental calculation in checking a calendar). Alongside the comic, the joke is that the mnemonic is supposed to be the real "cool mental calculation hack" which supposedly saves a lot of effort. This is similar to 1567: Kitchen Tips . There is also a joke that he is unsure if there are 31 days in October, although Halloween is a largely celebrated holiday on the 31st. [Cueball is thinking.] Cueball: Thirty days hath September, April, June and November Cueball: All the rest have 31—except February, which has 28, and leap year makes it 29. Cueball: Wait, which month was I listening for? Oh right, October. Cueball: Did I say "October" in there? Now I can't remember. Cueball: 30 days hath September... I get stuck in this loop every month.

Launch Status Check

Launch Status Check

https://www.xkcd.com/1596

https://www.explainxkcd.com/wiki/index.php/1596:_Launch_Status_Check

[A rocket is about to launch. A small object is near the top of the rocket.] Countdown: T-Minus 2 minutes Offscreen Voice 1: Tank and booster are go for launch. Offscreen Voice 2: Safety console? Offscreen Voice 3: Check. Safety- Offscreen Voice 4: Wait. [The small object moves to further to the right.] Offscreen Voice 1: What is it? Offscreen Voice 2: On the live feed- a cool bird just flew past the tower! [The launch scene now a background silhouette, the small object of everyone's attention is no longer on-panel.] Offscreen Voice 1: Whoa, what kind? Offscreen Voice 2: Like a hawk, maybe! Offscreen Voice 1: Could it be a vulture? Offscreen Voice 2: I doubt it. The wings were flat, not in a "V". Offscreen Voice 3: It could be an eagle! Offscreen Voice 2: Ooh! [The scene is returns to full contrast, with at least a token attention being paid to it, once more.] Offscreen Voice 1: This is launch control. We have a possible sighting of a cool bird. Halt the countdown. Offscreen Voice 2: Someone get some binoculars up here! Offscreen Voice 3: I want to see!

The first panel shows a rocket launch , which is a critical point in any space mission . Before this moment, a large technical staff has put in years of hard work, but all that work (and even lives) could be destroyed in a second if anything goes wrong during the launch . T-Minus 2 minutes means that there are only two minutes left before the rocket is actually launched, so at this moment everybody is very nervous and worried about the launch going wrong. Other texts from the panel refer to the usual checks before the launch, whose end is to ensure everything is ready. In the second panel, one of the people controlling the launch sees a "cool bird" on the live feed from the cameras controlling the operation. This should be of no importance at all, given the relatively much more serious matter of having years of work and possibly human lives at stake. However, the technical staff starts commenting on this cool bird and aborts the launch procedure as they are interested in the bird. This behavior would be absurd in real life. [ citation needed ] In the third panel, the two controllers attempt to identify the bird; the one on the right guesses maybe it is a hawk . Since the habitat of hawks and vultures overlap almost entirely, a birdwatcher is almost certain to accidentally confuse the two in their lifetime of birdwatching. Obviously having this knowledge of the habitat overlap, the controller on the left asks if the bird was a vulture. The controller on the right accurately notes that it probably was not a vulture since it is commonly known to ornithologists that vultures "hold their wings slightly raised in a "V" when seen head on." [1] . However, this demands that the original sighting of the bird must have included a flight pattern in which the bird not only "flew past the tower" as stated, but also flew towards the tower... even cooler! The title text goes on with the same absurd behavior: the crew restarts the countdown to launch the rocket, but only to follow the bird and get a closer look at it. The original space mission the rocket was designed for is completely ignored. This is even more absurd than the initial interest in the bird, given that a rocket designed to enter outer space is ill equipped to try to follow a bird and maneuver at the low elevation and at the relatively slow speed of a bird. This could also be a joke in the well known fanaticism of serious bird watchers, who think nothing of spur of the moment day long road trips (or flights!) in order to get to view an unusual bird. The vehicle pictured is not clearly identified, and it could also be totally fictional. It could be the Atlas V or the Ariane 4 launch vehicle. It also shows some similarity with the SpaceX Falcon 9 Heavy launch vehicle (albeit with stubbier strap-on boosters), named after the Falcon , another bird of prey. This would increase the absurdity of the situation. The bird being referred to by the launch-crew features as a mere mark on the comic-strip, consistent with scale against the rocket, but they are obviously trying to start to identify the rough species or group it belongs to from the wing geometry , the effortlessly soaring carrion-seeking vulture and the hawk that often uses a swooping attack upon its prey typically having very different wing configurations as matches their evolved lifestyle. [A rocket is about to launch. A small object is near the top of the rocket.] Countdown: T-Minus 2 minutes Offscreen Voice 1: Tank and booster are go for launch. Offscreen Voice 2: Safety console? Offscreen Voice 3: Check. Safety- Offscreen Voice 4: Wait. [The small object moves to further to the right.] Offscreen Voice 1: What is it? Offscreen Voice 2: On the live feed- a cool bird just flew past the tower! [The launch scene now a background silhouette, the small object of everyone's attention is no longer on-panel.] Offscreen Voice 1: Whoa, what kind? Offscreen Voice 2: Like a hawk, maybe! Offscreen Voice 1: Could it be a vulture? Offscreen Voice 2: I doubt it. The wings were flat, not in a "V". Offscreen Voice 3: It could be an eagle! Offscreen Voice 2: Ooh! [The scene is returns to full contrast, with at least a token attention being paid to it, once more.] Offscreen Voice 1: This is launch control. We have a possible sighting of a cool bird. Halt the countdown. Offscreen Voice 2: Someone get some binoculars up here! Offscreen Voice 3: I want to see!

Git

Git

https://www.xkcd.com/1597

https://www.explainxkcd.com/wiki/index.php/1597:_Git

[Cueball points to a computer on a desk while Ponytail and Hairy are standing further away behind an office chair.] Cueball: This is git. It tracks collaborative work on projects through a beautiful distributed graph theory tree model. Ponytail: Cool. How do we use it? Cueball: No idea. Just memorize these shell commands and type them to sync up. If you get errors, save your work elsewhere, delete the project, and download a fresh copy.

Git is a version control system, used to manage the code in many millions of software projects. It is very powerful, and was amongst the first widely adopted tools to use a distributed version control model (the "beautiful graph theory tree model "), meaning that there is no single central repository of code. Instead, users share code back and forth to synchronise their repositories, and it is up to each project to define processes and procedures for managing the flow of changes into a stable software product. Although very powerful, the command line of Git is notoriously difficult to master. Dozens of blog posts and websites (see [1] , [2] ), and even books ( [3] , [4] ) have been written to help users navigate this complexity. The difficulty of using Git in common situations is contradicted by the apparent simplicity of its use in tutorial-style situations. Committing and sharing changes is fairly straightforward, for instance, but recovering from situations such as accidental commits, pushes or bad merges is difficult without a solid understanding of the rather large and complex conceptual model. For instance, three of the top five highest voted questions on Stack Overflow are questions about how to carry out relatively simple tasks: undoing the last commit, changing the last commit message, and deleting a remote branch. This comic thus explores the difference between the idealised view of Git's architecture, and its actual typical usage. Tutorials for Git tend to use simple systems in their examples, and only deal with the most basic commands to get started, which can create the misleading impression that Git can be used effectively without extensive study. Due to this problem, compounded by the fact that Git's commands are named differently from similar commands in other version control systems, many users (including Cueball) are unable to use it beyond basic commands, and might try to avoid problems by saving their code outside Git, downloading a newer copy, and then re-applying their changes to the new copy instead of trying to understand and use the features that exist in Git to accomplish this task. Cueball suggests "just memoriz[ing] these shell commands and type them to sync up". He is probably referring to a sequence of commands such as: As long as every contributor to the project follows these principles, this may suffice for a while. But many situations may cause "errors": In a situation such as a merge conflict, Git will show an error message such as: Although Git experts can of course deal with such situations, the remedy proposed by Cueball is "save your work elsewhere, delete the project, and download a fresh copy". That is, to copy the files out of their local repository's working directory, delete that whole structure, then clone the remote repository again (and, implicitly, copy the saved work back again): Abandoning the old project likely means losing some work, but may be faster and give a more predictable outcome than attempting to salvage the situation. Applying this method to a mere merge conflict issue may prolong the issue however, as the merge conflicts may still be present. The title text suggests an alternative method for working around Git's complexities, which reflects common practice: knowing a "Git expert" who can help in any situation. Such experts are somewhat notorious for waxing lyrically about Git's strengths, so it may be necessary to win their favour by first letting them ramble enthusiastically about it. They will hopefully eventually give the exact commands needed. In practice, the question-and-answer site Stack Overflow is frequently used for this exact purpose. It may even be a reference to the infamous tweet " Git gets easier once you get the basic idea that branches are homeomorphic endofunctors mapping submanifolds of a Hilbert space " which has been discussed here but it is inconclusive whether a meaningful interpretation exists. Putting a telephone number of someone who "understands Git" into such a file is humorous because: In short: programmers use version control systems to track changes to code. Most of these version control systems are quite similar and easy to learn if you already know another one. Git is a version control system based on completely different principles, and most programmers find it difficult to wrap their heads around it (although Git also offers a large number of nontrivial benefits over standard version control systems, which is why it is used). Cueball is one of those programmers. This comic was referenced in an earlier version of the page for what if? #153, where Randall, due to a problem with git, had at one time erroneously posted a draft of his what if? piece on peptides. As of December 17th, 2016 the page read: Whoops This article is still in progress. An early draft was unintentionally posted here thanks to Randall's troubled approach to git , and it took a little bit to get everything sorted out and rolled back. Sorry for the mixup! On January 30, 2017, the page was updated with a completed article, Hide the Atmosphere . As of September 23, 2019, the page no longer contains any reference to this comic or Randall's earlier mistake with Git (or anything related to Git, for that matter). The comic 1296: Git Commit also features Git. [Cueball points to a computer on a desk while Ponytail and Hairy are standing further away behind an office chair.] Cueball: This is git. It tracks collaborative work on projects through a beautiful distributed graph theory tree model. Ponytail: Cool. How do we use it? Cueball: No idea. Just memorize these shell commands and type them to sync up. If you get errors, save your work elsewhere, delete the project, and download a fresh copy.

Salvage

Salvage

https://www.xkcd.com/1598

https://www.explainxkcd.com/wiki/index.php/1598:_Salvage

[Megan is shown standing at the rail of a ship with a microphone reporting the event shown in the background. A small helicopter and a larger two rotor model, lowering a rope with hook, are hovering over a crane ship with its hook down line going down in the water. It is depicted like a news screen as seen on TV. Below Megan are two headings. The first in a white insert with double frame, and the other written in white over the gray ocean water.] Historic Salvage Live [Four crane ships are shown lifting the bow part of the RMS Titanic. There are pontoons beneath the ship to help it float up. The name of the ship can be seen.] RMS Titanic [Both parts of the Titanic are now flown by helicopters, four for the stern and five for the bow. One helicopter for each part is a two rotor model. Ropes go from the helicopters down on each side of the ship parts to pontoons below them. Below in the ocean there are two crane ships.] [The two parts of the ship is now lowered in to a huge bowl of rice (labeled) standing at the coast just out of the ocean, which can be seen to the left. One of the five helicopters for the bow is missing. For scale there are drawn two trees to the left, and something is parked to the right, maybe a truck.] Rice

The RMS Titanic was a large ocean liner which, when it was completed in 1912, was the largest ship afloat. The ship famously hit an iceberg on its maiden voyage and sank, killing two-thirds of its complement (approximately 1,500 people) in one of the deadliest peacetime maritime disasters ever. As it sank, the Titanic broke into two pieces. The ship was lost for decades until the wreck site was discovered in 1985. A number of proposals have been made to salvage the wreck of the Titanic both before and since the wreck's discovery, famously fictionalised in the thriller novel and film Raise the Titanic! There could be a joke on this title as in Rice the Titanic, even though it would not be possible to mistake the two words when spoken in the majority of dialects of English. The general consensus at this time is that the wreck is too fragile to be salvaged intact. Numerous expeditions have been made to the wreck site since its discovery, with several parties (without any outside authorization) taking various artifacts from the site. A popular view is that the wreck is effectively a mass grave and that plundering the site for profitable artifacts is akin to grave-robbing. Most believe the wreck should be left where it is, intact. That said, explorers have already done notable damage to the wreck. This comic shows a fictional attempt to salvage the two main pieces of the Titanic wreck, which, as it likely would in real life, garners media coverage as a 'historic salvage'. The salvage seems to consist of several ships raising the hull via cables attached to some sort of buoyant sled placed under the hull (as might actually happen, except that the relative sizes of the ships and the hull are wrong; this method would require the salvage ships be much larger in proportion to what is being salvaged). This is followed by helicopters carrying the hull in unison, again via cables to the cradle (a much less practical operation). The hull halves are then dropped into a giant tub of rice. The entire salvage attempt is increasingly cartoonish and unrealistic, but the tub of rice takes this to another level. Also, the two parts of the Titanic collapsed when hitting the sea floor, and thus could not be moved as shown in the comic. See this video of How Titanic Sank . The punchline to the comic references the "rice myth," (as Randall calls it) a popularly disseminated method of salvaging consumer electronics (usually cell phones) which have been submerged in water. (See Research Shows Rice is the Answer for a Wet Mobile ). The method entails burying the wet device in a bowl of rice. This process is commonly claimed to dry the device, but investigation reveals that the process is only mildly effective (though not entirely a myth either, see below). This comic likely plays on the dual meaning of the word " salvage " in respect of electronics and maritime wrecks . The comic suggests that the wreck of the Titanic would benefit from being dried as quickly as possible, in a humorous contrast to actual reality. Surviving non-metallic material on board the ship may not benefit at all from drying. Far more ancient shipwrecks are best preserved by keeping the recovered timbers wet (but progressively desalinated, where applicable), cool and anoxic, at least while conserving chemicals such as Polyethylene glycol are infused into the wood to allow safe and gradual drying without causing further damage. Leather, cloth and other organic remains may have variations on this regime. Thus the rice might benefit an electronic device briefly exposed to water, but is not likely to benefit a ship that has been immersed for over a century, where the interest is in more than merely stabilizing the remaining metal hull and infrastructure. There are numerous on-line discussions of the technique with mixed levels of success. Critically, where rice is tested against other methods, rice appears to perform worse than other methods. Controlled experiments on this topic tend to show that silica gel (aka the "Do Not Eat" packets often found in boxes with electronics or pharmaceuticals) is the most effective drying agent, with mixed results for rice. (see Myth Debunked: Uncooked Rice Isn't the Best Way to Save Your Water-Damaged Phone , where it turns out that leaving the phone to air-dry may actually be the best solution). The title text tells of another hobby of Randall's . He likes to take advantage of the "rice myth" to post fake articles on how to save your wet cell phone. But the instructions turn out to be elaborate recipes for rice pilaf . It is unclear whether Randall's instructions would explain how to prepare the rice prior to inserting a phone (thus resulting a usable dish), or if the instructions would require the phone to be inserted into the dish before it became clear that the dish was a recipe for food and not a phone-saving measure, thus worsening the condition of the phone. This may also be a "punishment" by Randall to anyone who would follow instructions blindly before reading them through, as a recipe for rice Pilaf would likely be distinguishable from phone-saving instructions by someone who read the instructions through before attempting them. Or it may just be that Randall considers those who would follow instructions for saving a phone with rice that they find on the internet gullible enough to believe the seasonings and other ingredients would have a curative effect on electronics. The rice myth is revisited in one of the tips in 1820: Security Advice . [Megan is shown standing at the rail of a ship with a microphone reporting the event shown in the background. A small helicopter and a larger two rotor model, lowering a rope with hook, are hovering over a crane ship with its hook down line going down in the water. It is depicted like a news screen as seen on TV. Below Megan are two headings. The first in a white insert with double frame, and the other written in white over the gray ocean water.] Historic Salvage Live [Four crane ships are shown lifting the bow part of the RMS Titanic. There are pontoons beneath the ship to help it float up. The name of the ship can be seen.] RMS Titanic [Both parts of the Titanic are now flown by helicopters, four for the stern and five for the bow. One helicopter for each part is a two rotor model. Ropes go from the helicopters down on each side of the ship parts to pontoons below them. Below in the ocean there are two crane ships.] [The two parts of the ship is now lowered in to a huge bowl of rice (labeled) standing at the coast just out of the ocean, which can be seen to the left. One of the five helicopters for the bow is missing. For scale there are drawn two trees to the left, and something is parked to the right, maybe a truck.] Rice

Water Delivery

Water Delivery

https://www.xkcd.com/1599

https://www.explainxkcd.com/wiki/index.php/1599:_Water_Delivery

[Caption above the frame:] Now that Amazon is advertising one-hour delivery of bottled water, [A larger building complex is show on the left. An arrow goes to a blue bottle in a brown package in the middle of the frame. Another arrow continues over to Cueball on the right. The same building and Cueball is drawn below four more times. More and more bottles in packages are added. First two with a third arrow in between. Then six packages with water, so close that there are only smaller arrows at both ends. Then there is one long package from building to Cueball with 20 bottles close together, with small arrows at both ends of this package. Then finally this turns into a stream of water flowing through a package "pipe", shown with one arrow in the middle of the blue water. Again with small arrows at both ends of the pipe.] [Caption below the frame:] I vote we start calling municipal plumbing "on-demand hyperloop-style water delivery" and see if we can sell anyone on the idea.

Amazon has added bottled water to its line of on-line home order goods, which they are calling Prime Now . In served areas, which include Manhattan/Brooklyn , Baltimore , Atlanta , Miami , Dallas , Austin , Houston , Indianapolis , Chicago , Seattle , Portland , Los Angeles , Minneapolis , San Francisco , San Jose , San Antonio , Las Vegas , Sacramento , and Phoenix , many products – including but not limited to bottled water – are available to be delivered within one hour. So we are faced with the prospect of water, contained within plastic bottles, contained within cardboard shipping boxes. As increasing amounts of water are ordered, on-demand, or as the delivery time decreases to even quicker than an hour, this would show increasing numbers of packages passing from Amazon HQ (or its distribution hubs) to an arbitrary end-user as shown in the comic. Beyond a certain (already impractical) point, it might be better to merge packaging together into a single longitudinal structure through which one could first deliver back-to-back bottles of water, as shown in the second-to-bottom illustration, and then as water quantity needs increase beyond that model, eventually just 'pipe' the water without the plastic bottle or any packaging at all, as shown in the final illustration. (This would also solve the problems of what happens with the packaging at the destination, or how to return it to the source to make it easier to re-use.) While this could apply to one degree or another to any merchandise, for the purposes of the comic and for the reasons described next, water was chosen for this example – because that's really what existing water-mains do. And hence Randall 's recommendation or vote that we start calling the regular municipal plumbing "on-demand hyperloop-style water delivery." In order to promote any 'new' technology, various buzz-words are used, and here it is hyperloop , reminiscent of Elon Musk's ' piped transportation system ', which (from the outside, at least) appears to be taking discrete passenger units (trains, cars, buses and planes) and replacing them with a stationary pipe within which the passengers 'flow.' (Albeit, in this case, still within discrete internal vehicles, not entirely like Futurama's 'piped people', which might be a bit messier). Randall suggests trying to get someone to buy into this idea, only to later realize that they have just bought the idea of tap water. The comic also seems to jab at the unnecessary buying of bottled water, when most places in the western world have perfectly drinkable water in the pipes. However, not all recipients like mains water ( hardness , softness and various additional water-treatment chemicals can affect taste and the action of water with detergents, and in some cities it might even be unwise to drink tap water, at least for tourists), which is why there is still a healthy business for bottled water (of many brands with subtleties to taste) even in households and establishments with piped-water available. The other explanation, for cynics only, is that the marketing budget for bottled water creates the industry. See The Gruen Transfer episode on Bottled Water (season 2 episode 3 (#13)) where the marketing is considered. In the title text Randall tells that when he was a kid he was asking his parents why there were not an additional pipe for toothpaste next to the water pipe. Amazon thinking the "same way" is a sarcastic jab implying Amazon saw toothpaste tubes and wondered why water wasn't delivered the same way (in small bottles). Both are implied to be examples of childish ideas, but Amazon is actually following through on theirs. The idea of a toothpaste pipe is revisited in 1649: Pipelines . [Caption above the frame:] Now that Amazon is advertising one-hour delivery of bottled water, [A larger building complex is show on the left. An arrow goes to a blue bottle in a brown package in the middle of the frame. Another arrow continues over to Cueball on the right. The same building and Cueball is drawn below four more times. More and more bottles in packages are added. First two with a third arrow in between. Then six packages with water, so close that there are only smaller arrows at both ends. Then there is one long package from building to Cueball with 20 bottles close together, with small arrows at both ends of this package. Then finally this turns into a stream of water flowing through a package "pipe", shown with one arrow in the middle of the blue water. Again with small arrows at both ends of the pipe.] [Caption below the frame:] I vote we start calling municipal plumbing "on-demand hyperloop-style water delivery" and see if we can sell anyone on the idea.

MarketWatch

MarketWatch

https://www.xkcd.com/1600

https://www.explainxkcd.com/wiki/index.php/1600:_MarketWatch

[Blondie as a news anchor reports on the day's price swings in the DOW. To the left of her is a chart showing how the index suddenly went from "random" to tracing out Washington DC's skyline starting with the Lincoln Memorial, then the obelisk of the Washington Monument and finally the United States Capitol. After that the index goes back to normal "randomness". Two words are written at the top of the screen to the left and right:] MarketWatch DJIA Blondie: Wild swings on the markets today as investors noticed the DOW was tracing out a silhouette of the DC skyline, and everyone got too weirded out to break the pattern until they finished the capitol building. The general idea of manipulating the DJIA for goals unrelated to financial gains reminds of the Geohashing Bill Gates achievement . The Washington Monument was also part of the game in 1608: Hoverboard , just left of the starting area. Patterns in the stock market are also topic of 2101: Technical Analysis .

Blondie as a news anchor is reporting on the day's price swings on the stock market. It has been noticed that the Dow index has traced out the DC skyline. MarketWatch (as written above the skyline) is a website focused on stocks. The DJIA (as written on the screen) is the Dow Jones Industrial Average , commonly referred to as the Dow. It is a stock market index , meaning that it is a general indicator of how the market is running (in this case, an aggregate of how 30 major industrial companies are doing). The stock market is famous for having unpredictable price swings, but for them to specifically make a tracing of a skyline (or any recognizable image) would definitely weird out most investors. The DJIA has been featured previously in 426: Geohashing . DC refers to Washington, D.C. The DC skyline shown here traces out the Lincoln Memorial , the Washington Monument (an obelisk) and the United States Capitol , which are located in that order in a line down the National Mall . This , this , this and some of these photos show the skyline depicted in the comic. As seen in 276: Fixed Width , unusual patterns can be addictive to the point of harming those involved in the pattern's creation. The joke, however, rests in the fact that stock investors probably have a lot at stake, so following a pattern rather than pursuing gains would be uncharacteristic. Although some investors follow superstitious behavior (such as making trades to follow a pattern rather than make more obvious profits), many trades are now made by automated computer systems, which may recognize some types of patterns, but would not recognize the DC skyline, making it impossible for the stock market to continue to follow such a pattern merely because of the efforts of the human traders. Buying and selling stocks based on patterns in the price charts is a common, but controversial, method of investing. Many day traders and some professional investors still use stock patterns ( head and shoulders , trend lines , etc.) to make trades (see for instance Analyzing Chart Patterns ). Most professional investors and finance academics believe that this practice is random (see strong and weak efficient markets hypothesis ). In the title text it is noted that the markets again has been shaken by uncertainty (for the second day running, after the DC skyline incidence from the main comic). This time, it was because someone at NYSE (the New York Stock Exchange ) had set up a giant ouija board that was controlled by the movement of the stock tickers, thus, collectively, everyone at the NYSE, as all have some influence on those. The ouija is also known as a spirit board, a flat board marked with the letters of the alphabet, the numbers 0–9, the words "yes", "no" and possibly a few others. A movable indicator indicates a spirit's message by spelling it out on the board during a séance. Ticker tape was an early way of transmitting stock price, and it was run through a stock ticker which printed abbreviated company names as alphabetic symbols followed by numeric stock transaction price and volume information. Today this has been replaced with electronics, but the concept of the stock ticker lives on in the scrolling electronic tickers seen on brokerage walls and on financial television networks. If the stock exchange begins to look to spirit boards people will get worried (also maybe by the cryptic messages from beyond they are receiving via the stock ticker) explaining the uncertainty. Of course, some people might claim that this is not so far from how stock brokers decide what to do anyway… [Blondie as a news anchor reports on the day's price swings in the DOW. To the left of her is a chart showing how the index suddenly went from "random" to tracing out Washington DC's skyline starting with the Lincoln Memorial, then the obelisk of the Washington Monument and finally the United States Capitol. After that the index goes back to normal "randomness". Two words are written at the top of the screen to the left and right:] MarketWatch DJIA Blondie: Wild swings on the markets today as investors noticed the DOW was tracing out a silhouette of the DC skyline, and everyone got too weirded out to break the pattern until they finished the capitol building. The general idea of manipulating the DJIA for goals unrelated to financial gains reminds of the Geohashing Bill Gates achievement . The Washington Monument was also part of the game in 1608: Hoverboard , just left of the starting area. Patterns in the stock market are also topic of 2101: Technical Analysis .