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Faust 2.0

Faust 2.0

https://www.xkcd.com/501

https://www.explainxkcd.com/wiki/index.php/501:_Faust_2.0

[Over the left side of the main panel, below the middle, is a small panel partly outside the main one. The comic begins inside this panel where a devil drawn like Cueball, but with two small horns on his forehead, is shown from the waist up, raising one hand while moving into the main panel. In the caption below, we learn that the devil is Mephistopheles.] Mephistopheles: Mortal! I come offering a deal- [In the main panel, with all drawings right of the smaller one, we see the mortal, Cueball, sitting at his desk typing on his laptop. Mephistopheles, now drawn in full figure, has stopped before a sign on a stick in the floor reading it out loud while pointing at it with one hand and holding the other hand in front of his mouth. The text on the sign is visible but unreadable in itself.] Cueball: Read the sign. Mephistopheles: "By entering this room, you agree to forfeit your own soul rather than negotiate with the mortal residing therein..." Mephistopheles: Wait, you can't- Cueball: Too late. [Caption below the panel:] Mephistopheles encounters the E.U.L.A.

E.U.L.A. is short for End-user license agreement , a license that software makers often attach to their software but people do not usually read. Agreement to an E.U.L.A. is assumed when a user uses the software or service that the E.U.L.A. is attached to, which has led a case where users have unknowingly actually agreed to give away their immortal souls because of a clause in an E.U.L.A. However, in the European Union, all provisions of these agreements that aren't already codified in law actually are not legally enforceable, unless they could be read and agreed to before purchase and first use. A Faustian deal is done by someone who sells his soul to the devil for something desired in this life, a textbook example of wanting instant gratification. The mortal will get the things he wanted, but when he dies, he will have to suffer eternal torment. As the span of a human lifetime is an eye-blink compared to eternity, this is a really stupid thing to do. It is named after the folkloric character Faust , whose story has been the subject of numerous adaptations. In this comic, Cueball turns an E.U.L.A. around on Mephistopheles , the demon Faust sells his soul to in the stories, by posting a sign saying that anyone entering the room agrees to turn over their own immortal soul rather than negotiate with Cueball for his. It is unknown whether this clause applies only to demons or to everyone , which would be quite horrifying. The title text makes reference to how easy it is to cut open one's own hand while trying to open a newly-bought CD case. Incidentally, a pen works just fine, though the blood is referencing how Satanic contracts are signed in blood. The only blood on the E.U.L.A. contracts that Randall "signs" by opening a CD is the blood coming from when he cuts himself like this. A short time later, a similar demon was depicted in a similar fashion in 533: Laptop Hell , although with a trident and in Hell. Although not mentioned in the comic, he was also named Mephistopheles in the official transcript. [Over the left side of the main panel, below the middle, is a small panel partly outside the main one. The comic begins inside this panel where a devil drawn like Cueball, but with two small horns on his forehead, is shown from the waist up, raising one hand while moving into the main panel. In the caption below, we learn that the devil is Mephistopheles.] Mephistopheles: Mortal! I come offering a deal- [In the main panel, with all drawings right of the smaller one, we see the mortal, Cueball, sitting at his desk typing on his laptop. Mephistopheles, now drawn in full figure, has stopped before a sign on a stick in the floor reading it out loud while pointing at it with one hand and holding the other hand in front of his mouth. The text on the sign is visible but unreadable in itself.] Cueball: Read the sign. Mephistopheles: "By entering this room, you agree to forfeit your own soul rather than negotiate with the mortal residing therein..." Mephistopheles: Wait, you can't- Cueball: Too late. [Caption below the panel:] Mephistopheles encounters the E.U.L.A.

Dark Flow

Dark Flow

https://www.xkcd.com/502

https://www.explainxkcd.com/wiki/index.php/502:_Dark_Flow

[Beret Guy is sitting at a computer, and Cueball is sitting in an armchair, reading either a book or a newspaper.] Beret Guy: According to this A.S.T. paper, every galaxy is being pulled toward one area of the sky. [Only Cueball.] Beret Guy [off-panel]: They hypothesize that it may be due to a supermassive object beyond the edge of the visible universe. Cueball: Maybe it's your mom. Zing! [Only Beret Guy.] Beret Guy: Do you think? [Outside at night, on a rooftop. Beret Guy is looking up to the sky, next to a telescope.] Beret Guy: Pull harder, mom. Beret Guy: I Miss you.

This comic is about astronomy and the Your Mom jokes that have become increasingly widespread in urban parlance. Beret Guy is reading a research paper presumably discussing Dark Flow , an observed anomaly in the motions of the galaxies that some theorize is caused by an unobservable sibling universe or similarly supermassive object beyond the edge of the visible universe. Cueball sees this as an opportunity to make yet another Your Mom joke, implying that Beret Guy's mother is fat. But apparently, Beret Guy's mother is dead, or at least missing, and he takes the joke seriously. He looks toward the sky and wishes that his mom pull harder so that he could be with her. The joke has been turned onto itself. The title text is a continuation of Beret Guy's thoughts and refers to another piece of science phenomenon that has been observed in space, the Pioneer Anomaly . The Pioneer 10 and Pioneer 11 spacecraft had been slowed down by an (at the time) unknown force as they exited the solar system, which he says is caused by the force of his love, probably toward his mom. This force has since been explained entirely in 2012 by the probes being decelerated by thermal radiation. In 2310: Great Attractor , the more local Great Attractor is pulling Beret Guy so hard that he can sleep on vertical surfaces when it is close to the horizon. [Beret Guy is sitting at a computer, and Cueball is sitting in an armchair, reading either a book or a newspaper.] Beret Guy: According to this A.S.T. paper, every galaxy is being pulled toward one area of the sky. [Only Cueball.] Beret Guy [off-panel]: They hypothesize that it may be due to a supermassive object beyond the edge of the visible universe. Cueball: Maybe it's your mom. Zing! [Only Beret Guy.] Beret Guy: Do you think? [Outside at night, on a rooftop. Beret Guy is looking up to the sky, next to a telescope.] Beret Guy: Pull harder, mom. Beret Guy: I Miss you.

Terminology

Terminology

https://www.xkcd.com/503

https://www.explainxkcd.com/wiki/index.php/503:_Terminology

[Map of the world with North America centered. An "x" is placed near the east coast. Asia is labeled "The East" and Europe "The West."] "The East" <- West x (me) East -> "The West" [Caption below the frame:] This always bugged me.

This comic shows a map of the world. The X in the center, labeled "ME," indicates Randall 's approximate location in the U.S., and two arrows point west and east from it. The map uses a format, popular in America, that places the American continents centrally, therefore splitting Asia (parodied by "you-cut-asia-in-half" ). The comic then shows Europe labeled " The West " as it is commonly referred to, despite being located to the east of Randall, and Asia similarly labeled " The East ", despite being west of Randall. Randall is therefore annoyed with the common terms "the West" and "the East" referring to locations east and west of him respectively. "The East" and "the West" were defined in geographical terms from the traditional boundary between Europe and Asia . They were later expanded or (mis-)appropriated to include references to cultural, racial, political, and trade connections. Another east-west division comes from zero longitude (the prime meridian ): the Western Hemisphere and Eastern Hemisphere are defined in reference to it, and world maps are often centered on it. The fact that the prime meridian runs precisely though the Greenwich Observatory, in London, is an artifact of the British Empire's dominance —and British exploration of the world— in the 1700s and 1800s. In particular, British astronomical tables (made by the Royal Observatory in Greenwich , London) were widely used to determine longitude all over the world. The need for establishing a precise zero-longitude is one of the two technological necessities to make a sextant work as a tool to calculate accurate position for map making. In short, "the East" and "the West" should simply be viewed as a reference to map coordinates and not as relative to where you are as suggested by the comic. An America-centered map does not redefine "the East" or "the West" anymore than an Australian up-side-down reversed map redefines "the North" or "the South". The convention of orienting maps with north at the top and west at the left was started by the Greek geographer Ptolemy . In his work Geography , he introduced the first coordinate system with latitude and longitude. Randall shows some other possible map orientations in 977: Map Projections . The title text comments on the similarity in shape of New Zealand and Japan, and he suggests that one may in fact be the other in disguise, much like Clark Kent and Superman , as well as similar superhero alter ego pairs. The similarities between New Zealand and Japan are partly explained by the fact that both formed as volcanic island chains. [Map of the world with North America centered. An "x" is placed near the east coast. Asia is labeled "The East" and Europe "The West."] "The East" <- West x (me) East -> "The West" [Caption below the frame:] This always bugged me.

Legal Hacks

Legal Hacks

https://www.xkcd.com/504

https://www.explainxkcd.com/wiki/index.php/504:_Legal_Hacks

[Megan sits at her computer, Cueball standing behind her.] Megan: Another ISP's filtering content. Cueball: Thank God for Crypto. [Cueball stands alone; Megan is presumably off-panel left.] Cueball: It wasn't that long ago that RSA was illegal to export. Classified a munition. [Megan, sitting in her chair, is looking back towards Cueball, presumably off-panel right.] Megan: You know, I think the crypto community took the wrong side in that fight. We should've lobbied to keep it counted as a weapon. Cueball: Why? [She is now turned around in the chair looking at Cueball, who is in-panel again.] Megan: Once they get complacent, we break out the second amendment. [Cueball has his hand on his chin, contemplatively.] Cueball: ...Damn.

Megan notices that an Internet Service Provider (ISP) is blocking access to some webpages. Cueball is thankful that cryptography offers a way around such censorship. Encryption, the study and use of which is known as "cryptography," or "crypto" for short, is the art of transmitting messages that can only be read by the intended receiver(s) by using mathematical techniques to conceal ("encrypt") the data in the message. One common and effective way to encrypt messages is the RSA algorithm , which is based on the difficulty of integer factorization for products of two prime numbers. Being able to share unbreakable codes and decrypt other people's codes gives countries a military advantage - for example, in World War II, the Americans and British were often able to figure out where a German attack would be coming and send reinforcements there, because they had cracked the German codes . Because of this, the United States government initially tried to keep the mathematical details of strong encryption algorithms (including RSA) inside the country by classifying the algorithms as a weapon. It is a crime to share certain kinds of weapons technology with other countries without permission. Amateur and professional cryptographers, angry about the attempt to restrict their work, lobbied the government to change the rule and stop treating cryptography as a weapon, in part so that they could continue to collaborate with colleagues overseas, and in part because they wanted the ability to pass secret messages that the government could not easily decrypt. The export restrictions were gradually loosened and would have mostly been lifted by the year 2000. In the comic, Megan makes the provocative and counter-intuitive point that perhaps the cryptographic community could have best ensured easy access to the RSA technique by *allowing* the government to treat RSA as a weapon, and then, once everyone is certain that RSA is a weapon, invoking the Second Amendment to the United States Constitution , commonly known as the " right to bear arms " amendment (that is, the right to own and use weapons). In other words, if RSA were a weapon, it would be granted constitutional protections. This interpretation is likely a reference to the very strong social and political movements opposing arms control in the United States. The legal basis for this movement is the position that most or all laws prohibiting private ownership of firearms (and potentially other weapons), violate the Second Amendment. Accordingly, publicly referring to the Second Amendment tends to imply opposition to gun control. Megan's implication is that, by connecting RSA to this debate, crypto enthusiasts would gain a large group of unlikely allies who are strongly committed to keeping weapons legal and unrestricted. They could also invoke the legal cover of the Constitution, allowing them to fight restrictions in court. Cueball is surprised and impressed by this point, and pauses to contemplate Megan's strategy. It should be noted that there are major weaknesses in this argument. The Second Amendment only applies in the United States, meaning that imports and exports of munitions could still be banned. It might provide some protections against the ability of the US government to restrict RSA within US borders, but it could still be restricted in other countries, potentially hampering its use in global communications. The title text claims that this is a reasonable interpretation of the Constitution, because cryptography (a modern weapon) is analogous to muskets and cannons (the weaponry in use in the 1780s, when the Second Amendment was drafted). As evidence for the analogy, the title text points out that Jefferson would have been a big fan of cryptography, which is plausible, because President Thomas Jefferson (the 3rd President of the United States) was an amateur scientist who enjoyed studying a very wide variety of fields (in fact, he invented the Jefferson disk , an encryption device that was quite advanced for its time). The point is somewhat facetious, because it is hard to imagine a modern technique that Jefferson would not "be totally into." Also, the mere assertion that an early President would have been a fan of a technique is not very good evidence that the technique would be legally permitted by a particular Amendment. [Megan sits at her computer, Cueball standing behind her.] Megan: Another ISP's filtering content. Cueball: Thank God for Crypto. [Cueball stands alone; Megan is presumably off-panel left.] Cueball: It wasn't that long ago that RSA was illegal to export. Classified a munition. [Megan, sitting in her chair, is looking back towards Cueball, presumably off-panel right.] Megan: You know, I think the crypto community took the wrong side in that fight. We should've lobbied to keep it counted as a weapon. Cueball: Why? [She is now turned around in the chair looking at Cueball, who is in-panel again.] Megan: Once they get complacent, we break out the second amendment. [Cueball has his hand on his chin, contemplatively.] Cueball: ...Damn.

A Bunch of Rocks

A Bunch of Rocks

https://www.xkcd.com/505

https://www.explainxkcd.com/wiki/index.php/505:_A_Bunch_of_Rocks

[Cueball is standing in a desert with lots of rocks lying around. He is narrating his own situation. The first panel spans the entire width of the comic. The first line of text is written to the left of him, the second line to the right.] So I'm stuck in this desert for eternity. I don't know why. I just woke up here one day. [The next four panels take up the second line of the comic.] [Cueball stand in the desert.] I never feel hungry or thirsty. [Cueball walks in the desert.] I just walk. [Zooming out while Cueball continues to walk in the desert.] Sand and rocks [Zooming far out as Cueball again just stands in the desert. First line of text, above him, is a continuation of the text in the previous panel. The second line is below him.] stretch to infinity. As best as I can tell. [The next three panels take up the third line of the comic. The last takes up half the width.] [Cueball is sitting in the desert, in a contemplative position. First line of text above him, the second below.] There's plenty of time for thinking out here. An eternity, really. [Cueball is sketching stuff in the sand. First line of text above him, the second below.] I've rederived modern math in the sand and then some. [Three different graph types are depicted. First line of text above them, the second below.] Physics too. I worked out the kinks in quantum mechanics and relativity. Took a lot of thinking, but this place has fewer distractions than a Swiss patent office. [The next eight panels take up the fourth and fifth lines of the comic. All pictures are the same size.] [Cueball is walking along the desert, laying out rocks on a line. Four have been deployed. He is laying down the fifth and has a sixth in his other hand.] One day I started laying down rows of rocks. [Cueball, with a rock in his hand, continues to deploy rock 16, in a more intricate pattern. There are grid-lines in the sand (5 rows, 6 columns), with each intersection either empty of filled with a rock. No rocks lay anywhere but at an intersection on the grid.] Each new row followed from the last in a simple pattern. [Zooming out showing even more laid out rocks. Cueball is seen directly from above, and we see his shadow falling on the grid of rocks (7 rows, 14 columns).] With the right set of rules and enough space, [Continues to zoom further out showing clear triangular patterns (with no rocks) in the laid out grid of rocks. Cueball is not seen. (8 rows, 42 columns). First line of text above the grid, the second line below.] I was able to build a computer. Each new row of stones is the next iteration of the computation. [Zooming far out (no Cueball) with rows intersected by five clear V lines on top of them. The V's are drawn inside each other, with the smallest V at the top right, and the other V's starting just to the right of the previous one, and then continuing the same distance past the previous V, as the total length of the first V. The "*" in the first line of text above this grid references to the footnote below written in a smaller font.] Sure it's rocks instead of electricity, but it's the same* thing. Just slower. *Turing-complete [Cueball stands in a contemplative pose (on a clean white background - i.e. no dessert).] After a while, I programmed it to be a physics simulator. [A black panel with white drawings and text. A small white dot (a particle) is labeled by two arrows coming of two binary strings.] Every piece of information about a particle was encoded as a string of bits written in the stones. 00101010 00101010 [A Feynman diagram showing two particles interacting. Two arrows going in and out with a snaking line between them.] With enough time and space, I could fully simulate two particles interacting. [The next two panels take up the sixth line of the comic. The second panel takes up three-quarters of the width.] [Cueball standing before the vastness of the desert, with his programmed lines of rock stretching to infinity.] But I have infinite time and space. [A black panel with white drawings and text. Depiction of two large galaxies, one with four jets coming out of its center, the other a flat disc. Several smaller galaxies and/or stars are shown around them.] So I decided to simulate a universe. [The next four panels take up the seventh line of the comic. They are of similar widths.] [Cueball is walking by his grid of rocks, lines indicate he has just thrown another rock down in its place. It falls so hard it sinks into the sand that splashes out around it. The 14 rocks above him lie on the grid, four others below this grid have not been used yet.] The eons blur past as I walk down a single row. [Zoom far far out to show multiple rows of rocks. It is not very clear that there are several triangular patterns (with no rocks) in different sizes in the laid out grid of rocks. There are about 50 rows and 90 columns. There are six large triangles on top of each other at the left edge. To the right, there are three even larger triangles from top to bottom, the one in the middle further to the left than the one above, but further right than the bottom one.] The rows blur past to compute a single step. [Shows the placement of two particles in the simulation.] And in the simulation... [The two particles have moved just long enough as to not overlap with their previous positions, shown as an after-image with faint gray lines. The text continues directly the one from the previous panel.] another instant ticks by. [The next two panels take up the eighth line of the comic. They each take up half the width.] [A Cueball-like person (you) observes a mote of dust vanish.] So if you see a mote of dust vanish from your vision in a little flash or something [Cueball is standing between two rocks on the ground, while holding two rocks, one lifted up to his head. The first line of text is above him. It is a direct continuation of the text in the previous panel. The second line stands below to the right of him.] I'm sorry. I must have misplaced a rock sometime in the last few billions and billions of millennia. [Cueball stands in the "clean" part of his infinite desert, in front of the vastness of his infinity of infinite lines or rocks.] Oh, and... [A Cueball-like student sits in a classroom with his head in his hands, Megan sits behind him, and a teacher points to the blackboard. A clock shows the time at five minutes to ten.] If you think the minutes in your morning lecture are taking a long time to pass for you ...

Cueball awakens to find himself trapped for eternity in an endless expanse of sand and rocks. At first, he uses this time to derive all of mathematics and physics, plus more, including quantum mechanics and general relativity . Next Cueball creates a computer that can process any possible function, out of rocks and rules for the interaction between rocks. He then simulates a particle followed by the interactions between particles, followed by the entire universe. The amount of time it takes to simulate the change in the universe merely from one instant to the next takes an extremely long time, as the time it takes to update just one row of rocks would be eons, assuming a realistic time to place each rock. Cueball is using the rocks to build a cellular automaton , a computational model based on simple rules to advance from one state to the next. Certain cellular automata are Turing-complete , which means that they can be used to represent any conceivable algorithm if expanded infinitely, including simulating the physics of the universe. He specifically seems to be running Wolfram's Rule 110 , which is capable of universal computation. When using Rule 110 for universal computation, one builds a background pattern, which can be seen in the comic as the pattern of smaller triangles, and then performs computation by sending out "rockets" to collide and interact with each other. Cueball can simulate the functioning of an entire universe because he has unlimited time and space (and rocks). Cueball then apologizes for any flaws we see in the simulation. This implies that the audience is living in Cueball's simulation, making Cueball essentially God, and that he might make mistakes along the way. The final frame cuts to a classroom where a bored student stares at his hands waiting for class to end. Cueball admonishes the student for thinking that class is lasting forever, the joke being that the boredom felt in a classroom is nothing compared to the boredom that inspires Cueball to spend his endless time toiling to keep the universe moving. Indeed, the minutes of lecture actually took many "billions and billions of millennia" for Cueball to simulate. Another possible explanation is that the entirety of this comic is a fantasy in Cueball’s mind as he zones out during a math lecture. The title text suggests that Rule 34 should be called on Wolfram's Rule 34 . Rule 34 (see 305: Rule 34 ) is a humorous rule of the Internet that states, "If you can imagine it, there is porn of it. No exceptions." Wolfram's Rule 34 is a cellular automaton. Therefore, the title text says that either someone has made pornography featuring the cellular automaton in question, or someone has used the cellular automaton to produce pornography. The three diagrams in the "Physics, too. I worked out the kinks..." panel are, from left to right: The graph that represents particle interaction is a Feynman Diagram . This shows the interaction of subatomic particles that collide and exchange some momentum via a photon. The slope of the middle line represents the distance moved and the time lost/gained during the interaction. [Cueball is standing in a desert with lots of rocks lying around. He is narrating his own situation. The first panel spans the entire width of the comic. The first line of text is written to the left of him, the second line to the right.] So I'm stuck in this desert for eternity. I don't know why. I just woke up here one day. [The next four panels take up the second line of the comic.] [Cueball stand in the desert.] I never feel hungry or thirsty. [Cueball walks in the desert.] I just walk. [Zooming out while Cueball continues to walk in the desert.] Sand and rocks [Zooming far out as Cueball again just stands in the desert. First line of text, above him, is a continuation of the text in the previous panel. The second line is below him.] stretch to infinity. As best as I can tell. [The next three panels take up the third line of the comic. The last takes up half the width.] [Cueball is sitting in the desert, in a contemplative position. First line of text above him, the second below.] There's plenty of time for thinking out here. An eternity, really. [Cueball is sketching stuff in the sand. First line of text above him, the second below.] I've rederived modern math in the sand and then some. [Three different graph types are depicted. First line of text above them, the second below.] Physics too. I worked out the kinks in quantum mechanics and relativity. Took a lot of thinking, but this place has fewer distractions than a Swiss patent office. [The next eight panels take up the fourth and fifth lines of the comic. All pictures are the same size.] [Cueball is walking along the desert, laying out rocks on a line. Four have been deployed. He is laying down the fifth and has a sixth in his other hand.] One day I started laying down rows of rocks. [Cueball, with a rock in his hand, continues to deploy rock 16, in a more intricate pattern. There are grid-lines in the sand (5 rows, 6 columns), with each intersection either empty of filled with a rock. No rocks lay anywhere but at an intersection on the grid.] Each new row followed from the last in a simple pattern. [Zooming out showing even more laid out rocks. Cueball is seen directly from above, and we see his shadow falling on the grid of rocks (7 rows, 14 columns).] With the right set of rules and enough space, [Continues to zoom further out showing clear triangular patterns (with no rocks) in the laid out grid of rocks. Cueball is not seen. (8 rows, 42 columns). First line of text above the grid, the second line below.] I was able to build a computer. Each new row of stones is the next iteration of the computation. [Zooming far out (no Cueball) with rows intersected by five clear V lines on top of them. The V's are drawn inside each other, with the smallest V at the top right, and the other V's starting just to the right of the previous one, and then continuing the same distance past the previous V, as the total length of the first V. The "*" in the first line of text above this grid references to the footnote below written in a smaller font.] Sure it's rocks instead of electricity, but it's the same* thing. Just slower. *Turing-complete [Cueball stands in a contemplative pose (on a clean white background - i.e. no dessert).] After a while, I programmed it to be a physics simulator. [A black panel with white drawings and text. A small white dot (a particle) is labeled by two arrows coming of two binary strings.] Every piece of information about a particle was encoded as a string of bits written in the stones. 00101010 00101010 [A Feynman diagram showing two particles interacting. Two arrows going in and out with a snaking line between them.] With enough time and space, I could fully simulate two particles interacting. [The next two panels take up the sixth line of the comic. The second panel takes up three-quarters of the width.] [Cueball standing before the vastness of the desert, with his programmed lines of rock stretching to infinity.] But I have infinite time and space. [A black panel with white drawings and text. Depiction of two large galaxies, one with four jets coming out of its center, the other a flat disc. Several smaller galaxies and/or stars are shown around them.] So I decided to simulate a universe. [The next four panels take up the seventh line of the comic. They are of similar widths.] [Cueball is walking by his grid of rocks, lines indicate he has just thrown another rock down in its place. It falls so hard it sinks into the sand that splashes out around it. The 14 rocks above him lie on the grid, four others below this grid have not been used yet.] The eons blur past as I walk down a single row. [Zoom far far out to show multiple rows of rocks. It is not very clear that there are several triangular patterns (with no rocks) in different sizes in the laid out grid of rocks. There are about 50 rows and 90 columns. There are six large triangles on top of each other at the left edge. To the right, there are three even larger triangles from top to bottom, the one in the middle further to the left than the one above, but further right than the bottom one.] The rows blur past to compute a single step. [Shows the placement of two particles in the simulation.] And in the simulation... [The two particles have moved just long enough as to not overlap with their previous positions, shown as an after-image with faint gray lines. The text continues directly the one from the previous panel.] another instant ticks by. [The next two panels take up the eighth line of the comic. They each take up half the width.] [A Cueball-like person (you) observes a mote of dust vanish.] So if you see a mote of dust vanish from your vision in a little flash or something [Cueball is standing between two rocks on the ground, while holding two rocks, one lifted up to his head. The first line of text is above him. It is a direct continuation of the text in the previous panel. The second line stands below to the right of him.] I'm sorry. I must have misplaced a rock sometime in the last few billions and billions of millennia. [Cueball stands in the "clean" part of his infinite desert, in front of the vastness of his infinity of infinite lines or rocks.] Oh, and... [A Cueball-like student sits in a classroom with his head in his hands, Megan sits behind him, and a teacher points to the blackboard. A clock shows the time at five minutes to ten.] If you think the minutes in your morning lecture are taking a long time to pass for you ...

Theft of the Magi

Theft of the Magi

https://www.xkcd.com/506

https://www.explainxkcd.com/wiki/index.php/506:_Theft_of_the_Magi

[Black Hat is holding up a copy of Left 4 Dead . Danish is holding up a small harness.] Black Hat: Hey. I sold your Roomba on Craigslist so I could buy myself Left 4 Dead . Danish: But I eBayed your XBox so I could get this dueling harness for my Roomba! Black hat and Danish at the same time: Aww.

This comic is a satirical play on O. Henry 's short story " The Gift of the Magi ." In O. Henry's story, a couple with very little money goes to great lengths to purchase gifts for one another. The wife sells her prized possession, her hair, to purchase a fancy chain for her husband's prize possession, a watch; the husband sells his watch to purchase some fancy hair accessories (clips/combs) for his wife. The story is about selflessness, as each party sold their prize possession to purchase something to enhance the other's prize possession. In this comic, however, the opposite occurs: Black Hat stole Danish 's Roomba (an autonomous robotic vacuum cleaner) and sold it to buy a new game for his Xbox , while Danish stole Black Hat's Xbox and sold it to buy a "dueling harness" for her Roomba, highlighting their mutually destructive selfishness. Although these actions reflect their sociopathic personalities and are at each other's detriment, both are apparently touched by the simultaneity of their selfish actions and the symmetry of the consequences. This is a play on the reaction that readers typically have upon reading the O. Henry story: although neither of the characters can actually use their gift, the gifts are touching nevertheless because they are literal symbols of the self-sacrificing love the characters have for each other. The "dueling harness," also mentioned in the title text, is an invention by Randall , which presumably would allow Roombas to wield weapons and battle each other like the robots in Robot Wars . [Black Hat is holding up a copy of Left 4 Dead . Danish is holding up a small harness.] Black Hat: Hey. I sold your Roomba on Craigslist so I could buy myself Left 4 Dead . Danish: But I eBayed your XBox so I could get this dueling harness for my Roomba! Black hat and Danish at the same time: Aww.

Experimentation

Experimentation

https://www.xkcd.com/507

https://www.explainxkcd.com/wiki/index.php/507:_Experimentation

[Cueball and Megan are holding hands, and Megan is pointing off to the side.] Megan: Oh, hey, it's twelve of the dudes from control group B! [Caption below the panel]: I'm cool with her past lesbian experimentation, but I wish she hadn't insisted the experiments be scientifically rigorous.

College (undergraduate university, for international readers) is often a young adult's first experience with independent living. As a result, it is a time to "find yourself," so the aphorism goes. This often includes a certain amount of sexual experimentation, including same-sex experimentation. This comic applies a scientific interpretation to a colloquial expression (a favorite on xkcd ). Usually, "lesbian experimentation" refers to a woman engaging in one-night stands with other women to satisfy her curiosity about the experience and discover her own sexual orientation. Megan , however, does the "experimenting" according to the scientific method : hypothesize, experiment, draw conclusions, repeat. She formulates a hypothesis about her sexual orientation (apparently something along the lines of "I am a lesbian"), which she proceeds to test by experiments (sexual encounters) with female partners as the experimental group and male partners as the control group . She used large sample groups and multiple experiments (the reference to "control group B" implies at least two separate experiments). The title text implies that Megan "experimented" with the entire sophomore class (both males and females) before dating Cueball . [Cueball and Megan are holding hands, and Megan is pointing off to the side.] Megan: Oh, hey, it's twelve of the dudes from control group B! [Caption below the panel]: I'm cool with her past lesbian experimentation, but I wish she hadn't insisted the experiments be scientifically rigorous.

Drapes

Drapes

https://www.xkcd.com/508

https://www.explainxkcd.com/wiki/index.php/508:_Drapes

Cueball: So, does the carpet match the drapes? Woman: Yeah. But not the upholstery. [Woman walks away.] [Cueball scratches his head, confused.]

This comic plays on the classic question "does the carpet match the drapes," where the 'drapes' are the hair on someone's head, and the 'carpet' is their pubic hair. The assumption is that some people artificially dye their head hair, but typically would not dye other body hair, essentially asking "Are you a 'natural' red-head/blonde/etc.?" The classic question doesn't mention upholstery, hence Cueball 's confusion. There is some speculation about other body/arm/leg/arm-pit hair interpretations for upholstery . This comic could also be a self-referential joke where the furniture is a double entendre to the art of the comic itself. The "carpet" is the white background of the comic, which matches the black "drapes" of Cueball, the woman, and the words. The "upholstery," in this case, is the woman's hair, which is colored and heavily bordered to create a 3D effect, which does not at all match the rest of this comic. The fact that Cueball seems confused (as per the last panel and title text) suggests that the fourth wall may have been broken. Alternatively, it could be that the woman is wearing a wig , and the "upholstery" is her natural hair or something similar. Or the woman is talking literally about her home's decoration. Cueball: So, does the carpet match the drapes? Woman: Yeah. But not the upholstery. [Woman walks away.] [Cueball scratches his head, confused.]

Induced Current

Induced Current

https://www.xkcd.com/509

https://www.explainxkcd.com/wiki/index.php/509:_Induced_Current

[Beret Guy, extension cord in hand, approaches Cueball as he works at his computer.] Beret Guy: Can I plug my extension cord over here? Cueball: No. Beret Guy: Why? Cueball: Solar Flares. [A diagram is displayed, illustrating the Earth's magnetic field being permanently impacted by a large solar flare (represented by a large arrow).] [A second diagram is presented, illustrating the Earth's rotation and the resulting impact that the solar flare would have on the earth's magnetic field.] Cueball: A large solar flare could dent the Earth's magnetic field inwards. The Earth's spin could then induce a strong current in any long conductors, melting them and starting fires. By extending your cord, you could kill us all. [Stunned, Beret Guy looks down at the cord he carries.] Beret Guy: Really? Cueball: Warn your friends. [Dejected, Beret Guy walks away, cord in tow.] [Cueball looks up from his computer as he is braced by Megan, a stern look in her face.] Megan: That was mean. Cueball: Listen, somebody has to keep Mythbusters in business. Next season should be fun.

This comic is exaggerating the effects of the physics stated. Solar flares eject, among other things, ions, electrons, and radiation. The charged particles reach Earth after a day or two, and in history has knocked the power out in some areas during a large flare. They can marginally affect the magnetic field of the Earth, or dent it, as Cueball says. A voltage occurs in a conductor (the wire) when subjected to a changing magnetic field. However, this change is small and influences only very long conductors, such as telephone lines. Interestingly, phenomena as described by Cueball have occurred several times in recorded history, with effects quite nearly like those described, most notably the Carrington event of 1859. In 1859, a solar storm produced a series of powerful geomagnetic storms across the world, and many telegraph operators reported electrical phenomena (electric shock from the apparatus, messages sent and received despite disconnect from power sources, and pylons carrying telegraph lines sparking and arcing with current) all across North America. For this to occur in shorter conductors, (e.g., Beret guy's extension cord,) a solar storm would have to be so destructively large as to pose far more danger than just fires. The chances of such a solar event occurring again are not prohibitively small, though quite infrequent, and the last one, of comparative size and strength, was recorded in 2012 . Mythbusters is a show that tests urban legends or myths that viewers submit. They have a classic style of scaling up myths to comical sizes. By starting the myth that a fire would be formed from the large voltage across the wire induced by the Earth's magnetic field, Cueball hopes to see it tested on Mythbusters , and perhaps then scaled up to astronomical proportions. This comic may also reference how Mythbusters was running out of urban legends to test, and has resorted to testing the feasibility of viral videos, movie scenes, proverbs, and the like, plus occasionally making up urban legends. The title text refers to the Large Hadron Collider (LHC) , the most powerful particle collider in the world and the fear of some people of the production of stable microscopic black holes destroying the Earth. Of course, testing something like this would be outside the scope of a show like MythBusters . Additionally, if the myth was confirmed, the planet would be destroyed, and nobody would like the MythBusters anymore. However, that wouldn't be much of a problem, seeing that there would be no one around to like anything. [Beret Guy, extension cord in hand, approaches Cueball as he works at his computer.] Beret Guy: Can I plug my extension cord over here? Cueball: No. Beret Guy: Why? Cueball: Solar Flares. [A diagram is displayed, illustrating the Earth's magnetic field being permanently impacted by a large solar flare (represented by a large arrow).] [A second diagram is presented, illustrating the Earth's rotation and the resulting impact that the solar flare would have on the earth's magnetic field.] Cueball: A large solar flare could dent the Earth's magnetic field inwards. The Earth's spin could then induce a strong current in any long conductors, melting them and starting fires. By extending your cord, you could kill us all. [Stunned, Beret Guy looks down at the cord he carries.] Beret Guy: Really? Cueball: Warn your friends. [Dejected, Beret Guy walks away, cord in tow.] [Cueball looks up from his computer as he is braced by Megan, a stern look in her face.] Megan: That was mean. Cueball: Listen, somebody has to keep Mythbusters in business. Next season should be fun.

Egg Drop Failure

Egg Drop Failure

https://www.xkcd.com/510

https://www.explainxkcd.com/wiki/index.php/510:_Egg_Drop_Failure

[Boy tosses contraption off of building with egg in it.] [Egg cracks and little chick flies out while people look quizzically at the hatched egg.] Egg: Crack Chick: Chirp, chirp [Device with cracked egg lands on ground.]

A common competition for school -age children (e.g. in science fairs or summer camps ) is the ' egg drop ': each team is given an unbroken egg (either raw or boiled, and usually of a chicken ), and may be provided with an assortment of materials, e.g. newspaper, popsicle sticks, string, tape, etc. The challenge is to build a contraption that will allow the egg to be dropped from some specified height onto a hard surface without breaking. In some competitions, the rules permit the contraption to be constructed from any available materials; other times, it is limited to only the materials that have been provided. Scoring varies wildly - common elements are speed of assembly, mass of the contraption, creativity of design (as determined by judging or voting), and/or accuracy of landing within a target area - but one near-universal rule is disqualification if the egg's shell is broken. In the comic, the competitor fails, not because of any flaw in his design, but because the egg hatches unexpectedly during the fall. In reality, the hatching process usually takes many hours [1] [2] — much longer than the few seconds of a typical egg drop; furthermore, the newborn chick cannot fly immediately. However, if it were to magically happen as in the comic, then the competitor would be disqualified because the egg technically broke when the chick hatched from it. The title text suggests an alternate strategy, one Randall hears was successful in real life: select for your egg one that has not yet been laid. The hen provides both active lift with her wings and significant padding with her body and feathers, thus nearly guaranteeing that the egg will survive the fall. But the chicken may not be permitted in some contests if it is not one of the allowed materials. And even if it were, a chicken might be heavier than the usual contraptions of newspaper and string, [ citation needed ] so it might lose anyway if weight is one of the scoring criteria. [Boy tosses contraption off of building with egg in it.] [Egg cracks and little chick flies out while people look quizzically at the hatched egg.] Egg: Crack Chick: Chirp, chirp [Device with cracked egg lands on ground.]

Sleet

Sleet

https://www.xkcd.com/511

https://www.explainxkcd.com/wiki/index.php/511:_Sleet

[The comic is set on a rainy, cold, windy street; Megan is walking along said street with a scarf; narration is from Megan's point-of-view.] The weather outside is frightful. I hate trudging through the icy slush and biting sleet. But it beats lying in our warm, cozy bed Listening to you talk about DRM for hours on end. Offscreen: Come back! Just listen to this one quote from Free Culture!

Megan is seen leaving an apartment, trudging through freezing temperatures and foul weather , when she could be in a warm, cozy bed. The dialog is likely her thoughts, rather than speech. She is fed up with the second person's endless discussion of digital rights management (DRM). She probably agrees with his position, but would rather face the weather than his endless rehashing of the issue. The words in the first panel are the opening lyrics of the Christmas standard, Let It Snow! Let It Snow! Let It Snow! . In the last panel, Free Culture refers to a book by Lawrence Lessig , who advocates for fewer restrictions in many areas. Randall had previously advocated this title himself in 86: Digital Rights Management and 129: Content Protection , and mentioned Lessig in 343: 1337: Part 3 . In the title text, it is revealed that Megan herself is also guilty of droning on about 'boring' subjects, likely to the annoyance of those around her. In this case, complaining about science-fiction TV series Battlestar Galactica , which tends to produce strong reactions among geeks . She has gone outside to avoid the boring rant. However, given the opportunity, it is she who would be doing the ranting. [The comic is set on a rainy, cold, windy street; Megan is walking along said street with a scarf; narration is from Megan's point-of-view.] The weather outside is frightful. I hate trudging through the icy slush and biting sleet. But it beats lying in our warm, cozy bed Listening to you talk about DRM for hours on end. Offscreen: Come back! Just listen to this one quote from Free Culture!

Alternate Currency

Alternate Currency

https://www.xkcd.com/512

https://www.explainxkcd.com/wiki/index.php/512:_Alternate_Currency

[Cueball is standing in front of a televion] Television: With the collapse of the dollar, the government has endorsed an alternate currency. Your monetary worth is now determined by the number of funny pictures saved to your hard drive. [Caption below the panel:] I have been preparing for this moment my whole life.

Cueball is shown watching television, where it is announced that the US dollar has collapsed and been replaced by an 'alternative currency' of humorous pictures commonly shared on the internet (an Internet Meme ). Such a currency would be utterly useless; for untraceable and easily counterfeited .gif and .jpeg files to become more monetarily stable than the US dollar would mean that the economy is all kinds of screwed , to the point of utter absurdity. The title text pokes fun at users of 4Chan who are notoriously known for their habit of hoarding image macros, a practice he suggests is almost useless except in the instance jokingly suggested by the comic. 4Chan is also reputable for reducing the Happiness and Success of many people their community targets anonymously. Randall also pokes fun at himself in saying, "I have been preparing for this moment my whole life," indirectly implying he is also guilty of this practice. The "rare pepe" meme that has recently sprouted on 4chan implies that some photoshopped pictures of Pepe the frog are valuable and that they could be sold. 120 Rare pepe's reached a price of $99,166 on eBay before being removed as seen here. With the rise of cryptocurrency and NFTs, this absurdist comic is becoming indistinguishable from reality. [Cueball is standing in front of a televion] Television: With the collapse of the dollar, the government has endorsed an alternate currency. Your monetary worth is now determined by the number of funny pictures saved to your hard drive. [Caption below the panel:] I have been preparing for this moment my whole life.

Friends

Friends

https://www.xkcd.com/513

https://www.explainxkcd.com/wiki/index.php/513:_Friends

[Cueball is talking to Megan.] Cueball: I have a crush on you. [Cueball is shown alone.] Cueball: I could ask you out, and move on with my life if you said no. [Cueball has his arms out.] Cueball: Or, Cueball: WE COULD BE FRIENDS! [Cueball has one palm out.] Cueball: See, I don't want to consider that you might not be attracted to me. I'm scared of rejection, so I've decided relationships should grow smoothly out of friendships. [Megan is shown sitting at her computer.] Cueball: When you have problems, I'll be there for you, night after night. Cueball: Selflessly. Computer: *hug* [Megan is shown slamming a door and walking to Cueball to get a hug.] Cueball: I'll tear down the jerks you date, and wait for you to realize how good I am for you. That only I will ever understand you. SLAM Megan: Sniff Cueball: There there [Cueball is shown alone again.] Cueball: You don't want to hurt my feelings, and I won't ever force the issue. I'll tell myself it's because I "value our friendship." [Again.] Cueball: Bit by bit, I'll make you depend on me. [Cueball and Megan are shown sitting on a rock in a park, reading a book together.] Cueball: You'll think about how long it would take to build this kind of connection again. [Cueball and Megan are shown sitting on a couch drinking, getting closer, and kissing.] Cueball: And in a moment of weakness Cueball: and loneliness Cueball: you'll give in. [Megan is shown sitting at the computer with Cueball behind her facing the other way washing dishes.] Cueball: It'll feel comfortable and natural. You'll quietly revise your definition of love and try to be happy. And sometimes you will be. [Megan is shown sitting at the computer.] Cueball: Only the wistfulness in your gaze and the tiny pause before you say "I love you" will hint that this wasn't the ending you'd hoped for. Cueball: Sound good? [Megan is holding hands with another boy, talking to Cueball.] Megan: ...I'm going to date this jerk. Cueball: But he doesn't respect you!

Cueball is talking to Megan . He confesses that he has a crush on her. Usually the next step in Western cultures, when someone likes someone else, is to ask the other person out (in other cultures, such as Islamic or Indian cultures, it would be more appropriate to request that one's parents contact the parents of the person one has a crush on). But Cueball takes a different route, and in the comic, he explains his thought process. Presumably he actually explains this to Megan. He explains that he is afraid of rejection, and so instead of asking her out directly, promises to be her "best friend" and someone who is always "there for you," in the hopes that this will eventually lead to Megan developing an attraction for him. This way, Cueball does not have to risk Megan saying 'No' to him, as she will be led to make the first move instead. Cueball is aware that this may not be an ideal situation for Megan, conceding that she may end up changing her definition of happiness to make her feel more comfortable in the relationship, while she is conscious of the fact that she doesn't really love Cueball. Cueball recognizes that if Megan fell for him this way, she would probably have this fact at the back of her mind forever. And so, after painting this elaborate - but troubling - future, Cueball asks sound good ? Megan, however, is not won over by Cueball's plan, and she tells him that she is going to date "this jerk ", poking fun at him saying 'I will tear down the jerks you date'. (Although she could have said any name here -- to Cueball it will always sound like jerk !) This suggests that she would much rather date someone else rather than date Cueball whom she -- as he correctly implies -- does not love. Cueball declares that the other suitor doesn't respect you , an absurdly hypocritical comment given his manipulative plan. He explained earlier that he would tear down the jerks you date ; this last line could also be him actually executing on the plan he just detailed. The title text is a play on the concept of friends with benefits , wherein two friends have casual sex without entering a committed relationship. Friends with detriments suggests that having Cueball as her "friend" damages Megan's chances of getting a relationship (and sex) with anyone else, since Cueball will tear any candidate down. Also, despite Cueball claiming to be Megan's friend (and appearing to value this friendship), his plans are rather selfish and manipulative, making him a "friend" who is in fact detrimental. [Cueball is talking to Megan.] Cueball: I have a crush on you. [Cueball is shown alone.] Cueball: I could ask you out, and move on with my life if you said no. [Cueball has his arms out.] Cueball: Or, Cueball: WE COULD BE FRIENDS! [Cueball has one palm out.] Cueball: See, I don't want to consider that you might not be attracted to me. I'm scared of rejection, so I've decided relationships should grow smoothly out of friendships. [Megan is shown sitting at her computer.] Cueball: When you have problems, I'll be there for you, night after night. Cueball: Selflessly. Computer: *hug* [Megan is shown slamming a door and walking to Cueball to get a hug.] Cueball: I'll tear down the jerks you date, and wait for you to realize how good I am for you. That only I will ever understand you. SLAM Megan: Sniff Cueball: There there [Cueball is shown alone again.] Cueball: You don't want to hurt my feelings, and I won't ever force the issue. I'll tell myself it's because I "value our friendship." [Again.] Cueball: Bit by bit, I'll make you depend on me. [Cueball and Megan are shown sitting on a rock in a park, reading a book together.] Cueball: You'll think about how long it would take to build this kind of connection again. [Cueball and Megan are shown sitting on a couch drinking, getting closer, and kissing.] Cueball: And in a moment of weakness Cueball: and loneliness Cueball: you'll give in. [Megan is shown sitting at the computer with Cueball behind her facing the other way washing dishes.] Cueball: It'll feel comfortable and natural. You'll quietly revise your definition of love and try to be happy. And sometimes you will be. [Megan is shown sitting at the computer.] Cueball: Only the wistfulness in your gaze and the tiny pause before you say "I love you" will hint that this wasn't the ending you'd hoped for. Cueball: Sound good? [Megan is holding hands with another boy, talking to Cueball.] Megan: ...I'm going to date this jerk. Cueball: But he doesn't respect you!

Simultaneous

Simultaneous

https://www.xkcd.com/514

https://www.explainxkcd.com/wiki/index.php/514:_Simultaneous

[Cueball and Megan are in bed.] Cueball: Mmm, simultaneous orgasms. Megan: That wasn't simultaneous. Cueball: Huh? It totally was! [Caption below the panel:] A common disagreement when one of you is doing all the moving.

This comic links to en.wikipedia.org/wiki/Relativity_of_simultaneity . Cueball and Megan are talking about the sex they just had. Cueball is remarking on how they both achieved orgasm simultaneously, but Megan disagrees. This comic is a play on Einstein's theory of special relativity . One piece of the theory deals with two observers who are moving at close to the speed of light relative to each other. According to Einstein, events that appear simultaneous to one observer will appear to happen at different times to the other. So when one partner is moving and the other isn't, it's possible that they experience their orgasm at different times relative to each other. That would require one partner to be moving really fast in one direction, which would make them a really bad partner. [ citation needed ] On small speeds, this effect could not be measured. The other joke is that partners often disagree with each other — even when the difference is minor and not important to the matter. The title text is reference to the twin paradox, which arises from another piece of special relativity. In theory, if you stick one twin on a spaceship at near light speed and keep the other back on Earth, and assuming neither accelerates, each will perceive himself to age slowly while the other ages quickly, forming an apparent paradox. Megan expresses a preference for Cueball's older twin, who will be more "mature," meaning both older and presumably less combative about simultaneity. Again, the joke here is that at relativistic speeds, there could be disagreement about which twin is truly the "older" one. [Cueball and Megan are in bed.] Cueball: Mmm, simultaneous orgasms. Megan: That wasn't simultaneous. Cueball: Huh? It totally was! [Caption below the panel:] A common disagreement when one of you is doing all the moving.

No One Must Know

No One Must Know

https://www.xkcd.com/515

https://www.explainxkcd.com/wiki/index.php/515:_No_One_Must_Know

[Black Hat and Danish are talking and holding hands.] Black hat: You're my dearest darling danish. Danish: And you're my lovely cutie pie. Black hat: Well, you're- [Cueball enters.] [Black Hat and Danish look at each other and let go of each others hands.] [Black Hat holds a bloody sack, while Danish pushes down on a shovel to make a hole for what is presumably Cueball's body.]

Black Hat and Danish are more known for their sociopathy than their affection. In the first panel, they are affectionate towards each other, holding hands and using terms of endearment by calling each other cake names, i.e. danish pastry and pie . The entrance of Cueball , and his observation of this state, leads Black Hat and Danish to kill him and bury the evidence, so that no one knows that side of them, but 433: Journal 5 states that they are, in fact, in a relationship. The title text provides the alternative hypothesis that they were planning on killing him the whole time and were intentionally acting affectionate for the mental effect it would have on their victim. 542: Cover-Up provides a possible continuation of this story. [Black Hat and Danish are talking and holding hands.] Black hat: You're my dearest darling danish. Danish: And you're my lovely cutie pie. Black hat: Well, you're- [Cueball enters.] [Black Hat and Danish look at each other and let go of each others hands.] [Black Hat holds a bloody sack, while Danish pushes down on a shovel to make a hole for what is presumably Cueball's body.]

Wood Chips

Wood Chips

https://www.xkcd.com/516

https://www.explainxkcd.com/wiki/index.php/516:_Wood_Chips

[Cueball leans on desk; Woman sits behind desk.] Cueball: Did you ever figure out those mysterious woodchips? Woman: The ones in the hallway? No. Cueball: You didn't suspect that they matched the timber used in 1861 to build the "ghost ship" Mary Celeste, prompting you to send them to a lab for analysis, the results of which raised new and stranger questions? Woman: No, I threw them out. Why? [Caption below the panel:] My hoaxes need to get a lot less subtle.

Cueball has tried to play an elaborate hoax on a woman involving wood chips that match the composition of the wood used to build a 19th-century ghost ship called the Mary Celeste . Unfortunately, the woman has done the sensible, reasonable thing and thrown them out instead of checking to see if they belong to a ghost ship, whose wood chips or what-have-you would probably not have found their way to the hallway. This causes Cueball to realize that he needs to rethink the complicated way in which he creates hoaxes, because the people he is trying to trick do not follow through with his elaborate plans. The title text suggests that he also set up some kind of chemical match with the Shroud of Turin . The Shroud of Turin is a famous artifact bearing a ghostly image of a man's face, said by some to have been used to wrap the body of Jesus of Nazareth . Radiocarbon dating performed on the shroud in the late 1980s dated it to the Middle Ages (i.e. not old enough to have been used by Jesus); however, not everyone has accepted this finding. [Cueball leans on desk; Woman sits behind desk.] Cueball: Did you ever figure out those mysterious woodchips? Woman: The ones in the hallway? No. Cueball: You didn't suspect that they matched the timber used in 1861 to build the "ghost ship" Mary Celeste, prompting you to send them to a lab for analysis, the results of which raised new and stranger questions? Woman: No, I threw them out. Why? [Caption below the panel:] My hoaxes need to get a lot less subtle.

Marshmallow Gun

Marshmallow Gun

https://www.xkcd.com/517

https://www.explainxkcd.com/wiki/index.php/517:_Marshmallow_Gun

[A box above the first frame:] I got this gun that shoots marshmallows. [Cueball removes the red marshmallow gun from a box.] [Cueball shoots at Megan with marshmallow gun from offscreen.] Pop pop pop Whap whap whap [Megan facepalms.] Pop Megan: Sigh. [Megan removes a super soaker from desk drawer.] Pop pop [Megan shoots Cueball (offscreen) with the super soaker.] Cueball (offscreen): Augh! Fwoosh Cueball (offscreen): Man, I forgot that was there. [A box above the first frame of the second part of the comic:] The next day, everyone else got them too. [Megan and Beret Guy brandish marshmallow guns.] Megan: Hey, noob! Eat Stay-Puft®! [Megan shoots a marshmallow gun.] Pop pop pop [Cueball shoots a marshmallow gun.] Poppop pop [Megan and Cueball shoot marshmallows into the air, crossing the streams.] Beret Guy (offscreen): No! Don't cross the— [Between the last two frames is a wide gap with the following text:] Foom Giant monster (offscreen): Roaaar! [Megan, Cueball, and Beret Guy are all standing with weapons pointed at the ground looking up.] Megan: Okay, this is bad. Giant monster (offscreen): You're shooting what ?

Cueball has obtained a gun that shoots marshmallows and promptly decides to shoot at Megan . Having taken the first few hits without much reaction, she sighs and then brings out the super soaker, which was first used on her in 220: Philosophy (and later reappears in 2334: Slide Trombone ), and soaks him with it. The next day, everyone has such guns and starts shooting marshmallows at each other. We see Beret Guy and Megan who confront Cueball, saying Hey, noob ! Eat Stay-Puft® ! This is like saying eat lead when threatening someone with a regular gun, since Stay Puft is a fictional brand of marshmallows from the Ghostbusters movie. (Of course, it's also a reasonable thing to say, since marshmallows are good to eat.) [ citation needed ] These statements and many like them appear in many first-person shooter games with chat. Beret Guy realizes that the "streams" of marshmallows are about to cross and shouts a warning, but it is too late and they cross anyway. This results in something gigantic appearing with a Foom Roaaar! off-screen. It roars at the three friends. Megan looks up and states that this is bad as the giant shouts You're shooting what? Presumably the crossing marshmallow beams have recreated the Stay Puft Marshmallow Man from Ghostbusters . In the movie, crossing the ghost-capturing streams from the proton packs was " bad ." But in the end, in which an ancient spirit took the form of this giant Marshmallow Man, the monster was destroyed as a side effect of crossing the streams. The Stay-Puft man sees what they are shooting and is justifiably upset. The title text is a further Ghostbusters reference, as Bill Murray was one of the actors in the movie. Since the crossing of the streams of the proton packs by Bill Murray and the other Ghostbusters is related to the destruction of the Stay Puft Marshmallow Man in the movie, the crossing of the marshmallow streams in the comic does the opposite and summons an enormous Bill Murray. [A box above the first frame:] I got this gun that shoots marshmallows. [Cueball removes the red marshmallow gun from a box.] [Cueball shoots at Megan with marshmallow gun from offscreen.] Pop pop pop Whap whap whap [Megan facepalms.] Pop Megan: Sigh. [Megan removes a super soaker from desk drawer.] Pop pop [Megan shoots Cueball (offscreen) with the super soaker.] Cueball (offscreen): Augh! Fwoosh Cueball (offscreen): Man, I forgot that was there. [A box above the first frame of the second part of the comic:] The next day, everyone else got them too. [Megan and Beret Guy brandish marshmallow guns.] Megan: Hey, noob! Eat Stay-Puft®! [Megan shoots a marshmallow gun.] Pop pop pop [Cueball shoots a marshmallow gun.] Poppop pop [Megan and Cueball shoot marshmallows into the air, crossing the streams.] Beret Guy (offscreen): No! Don't cross the— [Between the last two frames is a wide gap with the following text:] Foom Giant monster (offscreen): Roaaar! [Megan, Cueball, and Beret Guy are all standing with weapons pointed at the ground looking up.] Megan: Okay, this is bad. Giant monster (offscreen): You're shooting what ?

Flow Charts

Flow Charts

https://www.xkcd.com/518

https://www.explainxkcd.com/wiki/index.php/518:_Flow_Charts

[A flow chart is shown beneath a caption. There are 14 boxes, five rhombus shaped and the rest rectangular. From all the rhombus boxes there are one arrow entering and two arrows leaving (with yes/no labels on them). One of the other boxes is the start with only one arrow leaving, and three of these boxes are endings with only one arrow entering. Three have two arrows entering and one leaving. And two have one in and one out. Caption:] A guide to understanding flow charts presented in flow chart form. Box 0: Start [Arrow to Box 1.] Box 1: Do you understand flow charts? [Arrow to Box 2.] Yes [Arrow to Box 4.] No Box 2: Good [Arrow to Box 3.] Yes Box 3: Let's go drink. [Arrow to Final Box.] 6 Drinks Box 4: Okay. You see the line labeled "Yes"? [Arrow to Box 6.] Yes [Arrow to Box 5.] No Box 5: But you see the ones labeled "No". [Arrow to End-Box 1.] Yes [Arrow to End-Box 2a.] No End-Box 1: Wait, what? [No Arrows.] End-Box 2a: Listen. [Arrow to End-Box 2b.] End-Box 2b: I hate you. [No Arrows.] Box 6: ...and you can see the ones labeled "No"? [Arrow to Box 2.] Yes [Arrow to Box 7.] No Box 7: But you just followed them twice! [Arrow to Box 8a.] Yes [Arrow to Box 8a.] No Box 8a: (That wasn't a question.) [Arrow to Box 8b.] Box 8b: Screw it. [Arrow to Box 3.] Final Box: Hey I should try installing FreeBSD!

Flowcharts are diagrams that represent processes in a graphical form. While predominantly used in computer programming to visualize the structure of source code, flowcharts can in theory be used to depict any real or virtual procedure. In this comic, this idea is subverted by employing a flowchart to explain how flowcharts work. Flowcharts are a recurring theme on xkcd, and a list of flowchart comics can be found here . This seems like a faulty basis for explaining anything, but the basic functionality of flowcharts is quite intuitive, and the attempted self-description is almost unnecessary. In fact, the comic does not actually explain how to use the flowchart: it just uses an example of a very simple flowchart to demonstrate to the reader that they can easily work out how to follow it. If the reader attempts to "game" the system by either giving contradictory answers, or refusing to acknowledge that they can see the "Yes" and "No" labels, the flowchart gets confused or becomes abusive. Just like a real computer. If you confirm or demonstrate that you can follow the flowchart, it inevitably leads to the "Let's go drink" box, which gives rise to the assumption that the whole chart was only a pretence for drinking. FreeBSD is a unixoid operating system for computers that is generally considered to require advanced skills [ citation needed ] . The question whether Linux or (Free)BSD is the preferable operating system is a question of almost [ citation needed ] religious belief to some. The comic takes a shot against FreeBSD by implying that one would only decide to install it when under the influence of alcohol. This may also be a reference to 349: Success . The title text mentions Microsoft Bob , a software package published in 1995 by Microsoft . The product was targeted towards beginners, and Microsoft decided to use a cartoon-style interface instead of a more 'professional' environment. It was a commercial failure [ citation needed ] , and still serves as an inside joke among IT professionals. Randall has made use of flowcharts before, and later he released another comic name 1195: Flowchart . [A flow chart is shown beneath a caption. There are 14 boxes, five rhombus shaped and the rest rectangular. From all the rhombus boxes there are one arrow entering and two arrows leaving (with yes/no labels on them). One of the other boxes is the start with only one arrow leaving, and three of these boxes are endings with only one arrow entering. Three have two arrows entering and one leaving. And two have one in and one out. Caption:] A guide to understanding flow charts presented in flow chart form. Box 0: Start [Arrow to Box 1.] Box 1: Do you understand flow charts? [Arrow to Box 2.] Yes [Arrow to Box 4.] No Box 2: Good [Arrow to Box 3.] Yes Box 3: Let's go drink. [Arrow to Final Box.] 6 Drinks Box 4: Okay. You see the line labeled "Yes"? [Arrow to Box 6.] Yes [Arrow to Box 5.] No Box 5: But you see the ones labeled "No". [Arrow to End-Box 1.] Yes [Arrow to End-Box 2a.] No End-Box 1: Wait, what? [No Arrows.] End-Box 2a: Listen. [Arrow to End-Box 2b.] End-Box 2b: I hate you. [No Arrows.] Box 6: ...and you can see the ones labeled "No"? [Arrow to Box 2.] Yes [Arrow to Box 7.] No Box 7: But you just followed them twice! [Arrow to Box 8a.] Yes [Arrow to Box 8a.] No Box 8a: (That wasn't a question.) [Arrow to Box 8b.] Box 8b: Screw it. [Arrow to Box 3.] Final Box: Hey I should try installing FreeBSD!

11th Grade

11th Grade

https://www.xkcd.com/519

https://www.explainxkcd.com/wiki/index.php/519:_11th_Grade

[Above a bar graph:] 11th-grade activities: [The y-axis is labeled:] Usefulness to career success [Above the x-axis are two small bars and one huge bar. Below the x-axis, each bar is labeled:] 900 hours of classes 400 hours of homework One weekend messing with Perl

This strip is a comparison about the time spent in 11th grade doing various things, and how important those things are to one's future. The first two bars on the chart are 900 hours of class, which is about 180 hours short of how many hours kids spend in school each year (most likely to show the lunch hour), and 400 hours of homework, or an average of about 2.2 hours per school day. Conversely, idly messing around in Perl (a programming language) for only one weekend is shown to have a much larger impact on one's future — specifically Randall's, as learning how to code would have been key to his job as a robotics engineer at NASA. This is likely due to the skills one can pick up in even just a single weekend in contrast to the often redundant, trivial, or generalist information that schools tend to convey. This is mainly a critique to how school subjects can be rather useless for one's future or that the school is so boring that students are discouraged to pay attention in class. The title text continues this sentiment; the fact that the subject of the conversation is left shrouded in mystery deepens the romance (in all senses of the word). [Above a bar graph:] 11th-grade activities: [The y-axis is labeled:] Usefulness to career success [Above the x-axis are two small bars and one huge bar. Below the x-axis, each bar is labeled:] 900 hours of classes 400 hours of homework One weekend messing with Perl

Cuttlefish

Cuttlefish

https://www.xkcd.com/520

https://www.explainxkcd.com/wiki/index.php/520:_Cuttlefish

[A scientist (looking like Cueball) is pointing into an aquarium tank with two small animals floating in the water. He explains that they are cuttlefish to Cueball and Megan, who are on the other side of the tank looking into it, Cueball with a hand to his mouth. Above them there is a frame inside the panel with a caption:] We visit a bio lab: Scientist: These are cuttlefish. [Very detailed drawing of a cuttlefish, with its special W shaped pupils, all eight arms and two longer tentacles, and the striped body with waving parts shown waving down each side. The scientist tells about the animal with text above and below.] Scientist (off-panel): They're frighteningly smart, have manipulating arms and tentacles, have ink jets, can dart backwards and see the polarization of light through their w-shaped pupils. Scientist (off-panel): And their sides are 200 dpi display screens which they use for camouflage and communication. [Back to the original setting where the scientist stands a little farther back from the tank with his arms down. Cueball and Megan have also moved farther back and are even leaning away from the tank.] Scientist: When we realized how intelligent they were, we began to teach them. Scientist: They've advanced quickly. Scientist: Cuttlefish: GO. [The two cuttlefish float straight out of the tank (lines indicating the movement and water splashing at the surface of the tank). The scientist looks down at them, while Cueball and Megan are holding hands and leaning farther back and Cueball taking his hand back to his mouth.] [Pan to only the scientist, standing with one arm bend in front of him and the other holding a finger up to his mouth, and the tank from where the cuttlefish now fly toward Cueball and Megan, who are now off-panel. Lines behind the cuttlefish show that they fly right but bob up and down. The cuttlefish talk in a strange way where the letters are alternately up and down.] Cuttlefish: K i l l t h e P h y s i c i s t s Cuttlefish: K i l l t h e P h y s i c i st s [Pan to Megan and Cueball, with the tank almost inside the left frame. Both cuttlefish are surrounded by their own zigzag lines, which then extend from them in a thin line to encompass either Cueball or Megan. Cueball was running away from them, when this happens, with legs bent at the knees and arms out, one bent. Megan has fallen, lying face down with her arms out.] [In this panel with faint gray shading, Cueball is waking up in bed from the dream, rising up to a sitting position suddenly as indicated with two movement lines behind his head. One arm is supporting him on the bed next to the pillow, and the other is pulling his sheet down away from his torso. The first sentence is maybe still part of the dream, as there is no line from Cueball to the sentence, and it is written high up. There is a line to the second sentence.] Cueball: Oh god. Cueball: I knew it. [This panel is divided into five segments. At the top, there is a large caption in two lines. There are three drawings following each other from left to right. First, a bottle is pouring liquid into a an Erlenmeyer flask (a conical laboratory flask) that is half full. Then, Cueball takes the flask and holds it up as a salute. Finally, he drinks from it, leaning his head way back. Below there is more text.] xkcd Salutes Bio Majors If we join you against the chemists, will you train your fleshy minions to leave us alive?

It appears that Cueball and Megan are physicists visiting a biology lab. Their guide, a biologist looking like Cueball, gives them a description of the humble cuttlefish that is both accurate and makes them sound like other-worldly creatures with highly advanced capabilities. The scene takes an unusual turn when the scientist implies that the cuttlefish have been easily trained to improve their capabilities. He then demonstrates this by giving a simple command, whereupon the cuttlefish rise out of the water, only to attack and kill both Cueball and Megan, demonstrating an ability to fly, talk, and discharge lethal electric shocks in the process. (See also 35: Sheep ). This is all revealed to be a dream, but it has given Cueball a warning not to underestimate the biologists. Apparently, they can be just as crazy and dangerous as any other kind of scientist. Cueball (who represent Randall as it is xkcd that salutes in the final panel) offers a toast to all biologists everywhere and plans an alliance with them against the chemists , hoping to prevent further attacks on physicists. He is then shown drinking from a laboratory flask, something that any scientist would be wary of. In the past, Randall has been somewhat dismissive of the non-math/non-physics scientific disciplines, so this comic may be trying to mend some bridges with biologists. But not with chemists. In the title text, CS stands for Computer Science . The "robot revolution" references events in film and literature, wherein robots, having become commonplace in the workforce, achieve independent thought and declare war on humanity, like in The Terminator , The Matrix , or the movie I, Robot . Randall implies that the physicists will switch sides if the robot revolution arrives first. Cephalopod is the class of animals that encompasses cuttlefish, as well as squids and octopodes . [A scientist (looking like Cueball) is pointing into an aquarium tank with two small animals floating in the water. He explains that they are cuttlefish to Cueball and Megan, who are on the other side of the tank looking into it, Cueball with a hand to his mouth. Above them there is a frame inside the panel with a caption:] We visit a bio lab: Scientist: These are cuttlefish. [Very detailed drawing of a cuttlefish, with its special W shaped pupils, all eight arms and two longer tentacles, and the striped body with waving parts shown waving down each side. The scientist tells about the animal with text above and below.] Scientist (off-panel): They're frighteningly smart, have manipulating arms and tentacles, have ink jets, can dart backwards and see the polarization of light through their w-shaped pupils. Scientist (off-panel): And their sides are 200 dpi display screens which they use for camouflage and communication. [Back to the original setting where the scientist stands a little farther back from the tank with his arms down. Cueball and Megan have also moved farther back and are even leaning away from the tank.] Scientist: When we realized how intelligent they were, we began to teach them. Scientist: They've advanced quickly. Scientist: Cuttlefish: GO. [The two cuttlefish float straight out of the tank (lines indicating the movement and water splashing at the surface of the tank). The scientist looks down at them, while Cueball and Megan are holding hands and leaning farther back and Cueball taking his hand back to his mouth.] [Pan to only the scientist, standing with one arm bend in front of him and the other holding a finger up to his mouth, and the tank from where the cuttlefish now fly toward Cueball and Megan, who are now off-panel. Lines behind the cuttlefish show that they fly right but bob up and down. The cuttlefish talk in a strange way where the letters are alternately up and down.] Cuttlefish: K i l l t h e P h y s i c i s t s Cuttlefish: K i l l t h e P h y s i c i st s [Pan to Megan and Cueball, with the tank almost inside the left frame. Both cuttlefish are surrounded by their own zigzag lines, which then extend from them in a thin line to encompass either Cueball or Megan. Cueball was running away from them, when this happens, with legs bent at the knees and arms out, one bent. Megan has fallen, lying face down with her arms out.] [In this panel with faint gray shading, Cueball is waking up in bed from the dream, rising up to a sitting position suddenly as indicated with two movement lines behind his head. One arm is supporting him on the bed next to the pillow, and the other is pulling his sheet down away from his torso. The first sentence is maybe still part of the dream, as there is no line from Cueball to the sentence, and it is written high up. There is a line to the second sentence.] Cueball: Oh god. Cueball: I knew it. [This panel is divided into five segments. At the top, there is a large caption in two lines. There are three drawings following each other from left to right. First, a bottle is pouring liquid into a an Erlenmeyer flask (a conical laboratory flask) that is half full. Then, Cueball takes the flask and holds it up as a salute. Finally, he drinks from it, leaning his head way back. Below there is more text.] xkcd Salutes Bio Majors If we join you against the chemists, will you train your fleshy minions to leave us alive?

2008 Christmas Special

2008 Christmas Special

https://www.xkcd.com/521

https://www.explainxkcd.com/wiki/index.php/521:_2008_Christmas_Special

The 2008 XKCD Christmas Special Due to the slowing economy, we could only afford to produce the prime-numbered panels. You should be able to infer the missing parts of the story easily enough. We apologize for the inconvenience. [The first panel is blank.] [Megan carrying Christmas lights and Cueball watching.] Megan: I'm going to one-up those Christmas light displays on YouTube. [Megan thinking.] Megan: Hmm. Needs more flair. Do you know what happens when you fire sodium pellets into a snowbank? Cueball: No. Megan: Me neither. [The next panel is blank.] [Megan sitting in front of a console.] Megan: Whoops, one of the Arduino control boards sublimated. Megan: If only I could make it self-repairing... [The next panel is blank.] Megan: Shit. The system has become sentient. Cueball: Friggin' Python. System: GRAAARR! [The next three panels are blank.] [Megan showing laptop to Cueball.] Megan: But according to this email forward, Santa is secretly a Muslim! Cueball: It explains everything! [The next panel is blank.] Megan: Okay, the cloned raptors are hunting the last of the cyborgs. We're safe. Cueball: Are you sure you thought this through? [The next three panels are blank.] [Two couples appear in this next panel.] Cueball: Are the raptors contained? Ponytail: Sure. Unless they figure out how to build lightsabers. [The next panel is blank.] [Guy with hat fighting with a raptor using lightsabers.] Cueball: It's all right. I've got her. [Lightsaber appears from behind.] Snap-hiss! Cueball: ...Clever girl. [The next three panels are blank.] [Bill Gates is holding a weapon over Santa's body. The two girls are watching.] Megan: Great. Bill Gates kills Santa. Bill Gates: I thought it was Stallman with a dyed beard. [The next five panels are blank.] [Danish and Black Hat are looking at a tree.] Danish: Where did you get this Christmas tree? Black Hat: Nowhere. Danish: Did you cut down the Yggdrasil? Black Hat: ...Maybe. [The next panel is blank.] [Megan and Cueball holding hands and looking at reader.] Merry Christmas from XKCD <3 [The last panel is blank.]

This comic is the xkcd Christmas Special from the year 2008. The prologue states that due to the 2008 financial crisis , only very few images of the strip could be produced, leaving the others to be blacked out. It is therefore left to the reader to reconstruct the whole story based on the given images. While it is claimed that the reconstruction should be rather easy, the complicated and abstruse plot-line makes it nearly impossible to fill the gaps. Any attempt at inferring the missing images would therefore be largely guesswork. The comic features the well-known xkcd characters getting involved in a strange fight with cyborgs and raptors on Christmas Eve. The line "We apologize for the inconvenience." is possibly a reference to the famous book series The Hitchhikers Guide To The Galaxy by Douglas Adams . It appears there as God's Final Message to His Creation, written in letters of fire on the side of the Quentulus Quazgar Mountains. Panel 2: Megan strives to outdo some Christmas lights she has seen on YouTube. Panel 3: Dissatisfied with her work, Megan is thinking about alternative ways improve her light arrangement. The idea of firing Sodium pellets into snow is probably a bad one, as Sodium reacts exothermically with water and may, in large amounts, induce explosions. Panel 5: Probably still obsessed with the idea of creating a large and impressive light display, Megan has constructed an electronic device with an Arduino processor, perhaps to make the light chain show patterns. However, the amount of energy she used was apparently too high, causing one of the control boards to sublimate- go directly from a solid to a gaseous state without an intermediate liquid phase. She then wishes she could make the system self-repairing. Panel 7: Megan's device has developed artificial intelligence , allowing it to feel. This is presumably a result of Megan attempting to make the device self-repairing. This common trope in science-fiction works usually leads to the system's attempting to eradicate its creator. Cueball attributes the emergence of a personality to awesome ease and power of programming in Python . Panel 11: Out of context, this panel introduces the idea of Santa Claus being a Muslim . This may be a reference to the persistent Internet rumors that Barack Obama is a Muslim, though he declares himself to be a Christian. However, the statement could also relate to the fact the Santa Claus is usually displayed with a large beard, which is sometimes also sported by conservative Muslims. Or it could just be non-sensical. Panel 13: At this point the self-aware Christmas light control systems has apparently released cyborgs that tried to kill Megan and Cueball. In order to repel the cyborgs, they have cloned Velociraptors . Cueball expresses doubt whether that was really a good idea. Velociraptors appear frequently in xkcd, as seen in these comics Panel 17: As predicted, the raptors have gone wild, but Megan, Cueball and the two smaller characters (perhaps their children) managed to cage the dinosaurs. They believe themselves safe unless the raptors learn how to build lightsabers . This is a reference to a line in Jurassic Park where the main characters believe themselves safe, unless the raptors can learn how to open doors. Panel 19: The raptors have indeed succeeded with constructing lightsabers and must now be fought. The "Clever girl" is a reference to a line from Jurassic Park where the raptors outflank (and kill) one of the human characters wearing a similar hat. Panel 23: IT billionaire Bill Gates has mistakenly killed Santa Claus, possibly in a sword fight. He claims to have mistaken him for Richard Stallman , a prominent free software activist. (Gates strongly opposes the idea of free software and is therefore considered an antagonist by many of its supporters.) The most striking resemblance between Stallman and Santa Claus is probably the long and untamed beard. Comic 225 is one of the most famous xkcd comics and features Stallman involved in a sword fight. Panel 29: Megan, possibly Danish , asks Black Hat where he obtained the enormously large christmas tree that can be seen on the right side of the picture. It is implied that he logged Yggdrasil , a giant ash tree in Norse mythology. According to tradition, Yggdrasil is the world tree representing the whole of creation and holding together the cosmological structure. Panel 31: Randall wishes Merry Christmas to all xkcd readers. The title text refers to panel 7. In Python, modules are imported using the "import module " syntax. Skynet is a self-aware artificial intelligence system featured in the Terminator film series as the main antagonist. Importing the skynet module might therefore account for Megan's system's developing an evil personality. Note that this comic was first published in another version that had panel 29 as panel 27 and the "Merry Christmas from xkcd" message at the bottom. As 27 is not a prime number , the current version was published in lieu of the erroneous one. It has been observed that the top left nine panels form a Glider in Conway's Game of Life . The glider is sometimes used as an emblem representing hacker subculture , although rotated by 90 degrees. It remains however unclear whether the occurrence in the comic is intentional or owed to the prime number pattern. The 2008 XKCD Christmas Special Due to the slowing economy, we could only afford to produce the prime-numbered panels. You should be able to infer the missing parts of the story easily enough. We apologize for the inconvenience. [The first panel is blank.] [Megan carrying Christmas lights and Cueball watching.] Megan: I'm going to one-up those Christmas light displays on YouTube. [Megan thinking.] Megan: Hmm. Needs more flair. Do you know what happens when you fire sodium pellets into a snowbank? Cueball: No. Megan: Me neither. [The next panel is blank.] [Megan sitting in front of a console.] Megan: Whoops, one of the Arduino control boards sublimated. Megan: If only I could make it self-repairing... [The next panel is blank.] Megan: Shit. The system has become sentient. Cueball: Friggin' Python. System: GRAAARR! [The next three panels are blank.] [Megan showing laptop to Cueball.] Megan: But according to this email forward, Santa is secretly a Muslim! Cueball: It explains everything! [The next panel is blank.] Megan: Okay, the cloned raptors are hunting the last of the cyborgs. We're safe. Cueball: Are you sure you thought this through? [The next three panels are blank.] [Two couples appear in this next panel.] Cueball: Are the raptors contained? Ponytail: Sure. Unless they figure out how to build lightsabers. [The next panel is blank.] [Guy with hat fighting with a raptor using lightsabers.] Cueball: It's all right. I've got her. [Lightsaber appears from behind.] Snap-hiss! Cueball: ...Clever girl. [The next three panels are blank.] [Bill Gates is holding a weapon over Santa's body. The two girls are watching.] Megan: Great. Bill Gates kills Santa. Bill Gates: I thought it was Stallman with a dyed beard. [The next five panels are blank.] [Danish and Black Hat are looking at a tree.] Danish: Where did you get this Christmas tree? Black Hat: Nowhere. Danish: Did you cut down the Yggdrasil? Black Hat: ...Maybe. [The next panel is blank.] [Megan and Cueball holding hands and looking at reader.] Merry Christmas from XKCD <3 [The last panel is blank.]

Google Trends

Google Trends

https://www.xkcd.com/522

https://www.explainxkcd.com/wiki/index.php/522:_Google_Trends

Bloggers were recently amused to discover that, according to Google Trends, the search term: "men kissing" is most popular in conservative Utah. A few other embarrassing correlations: [A two column table] [On the left side of the table:] Search Term Installing Ubuntu Running for President in 2010 Lincoln Fan Fiction Raptors on Hoverboards How is babby formed? I hate this website [On the right side of the table:] Top City Redmond, WA Wasilla, AK Chicago, IL Somerville, MA Wasilla, AK Mountain View, CA

Google keeps track of which searches are most popular in which regions as part of more general data mining to improve their service. For the enjoyment/education of others, they release select, non-personal parts of this data under the banner " Google Trends ." The first statistic – that "Men kissing" was popular in Utah , a state known for possessing a large population with very conservative social values, including opposition to homosexuality – is real. The others are made up for the sake of the joke. In order: With regards to the excerpt Randall provides in the title text: Bloggers were recently amused to discover that, according to Google Trends, the search term: "men kissing" is most popular in conservative Utah. A few other embarrassing correlations: [A two column table] [On the left side of the table:] Search Term Installing Ubuntu Running for President in 2010 Lincoln Fan Fiction Raptors on Hoverboards How is babby formed? I hate this website [On the right side of the table:] Top City Redmond, WA Wasilla, AK Chicago, IL Somerville, MA Wasilla, AK Mountain View, CA

Decline

Decline

https://www.xkcd.com/523

https://www.explainxkcd.com/wiki/index.php/523:_Decline

[Cueball is pointing at a line graph at a specific point where it slopes down. The y-axis shows that as y increases, love increases.] Cueball: Our relationship entered its decline at this point. Megan [Outside of panel]: That's when you started graphing everything. Cueball: Coincidence!

Cueball , apparently concerned about the status of his romantic relationship, has constructed a "relationship graph" plotting an ambiguously quantitative metric for love and/or affection against what is presumably time (the x -axis is not actually labeled; ironically in 833: Convincing Cueball states that not labeling graph axes is a relationship deal-breaker). He has identified a sudden drop. Cueball's romantic partner (probably Megan ) notes from off screen that the drop corresponds to the moment Cueball's obsession with graphs began. He claims the two events are coincidental, thereby referencing the recurring xkcd theme of correlation not necessarily implying causation – see 552: Correlation . The title text references Fourier transformation . The Fourier transform is a technique for discovering the periodic characteristic(s) of a function. A spike at one month on the Fourier transform of the love graph would mean that something happens every month that causes the relationship to change. This is presumably a reference to Megan menstruating, although this isn't proven. This is not something you should mention to your girlfriend and she asks him to stop talking before he finishes the sentence. After this graph the relationship may very well end... Fourier transformations were mentioned previously in 26: Fourier . [Cueball is pointing at a line graph at a specific point where it slopes down. The y-axis shows that as y increases, love increases.] Cueball: Our relationship entered its decline at this point. Megan [Outside of panel]: That's when you started graphing everything. Cueball: Coincidence!

Party

Party

https://www.xkcd.com/524

https://www.explainxkcd.com/wiki/index.php/524:_Party

Black Hat: And so I hired Rick Astley to show up at her party. Cueball: And rickroll her? Isn't that a little...last year? Black Hat: Ah, but he's not going to sing. Danish: Hey is that Rick Astley? Ponytail: I think it is. He just came in. Danish: Oh no. Brace yourself. Danish: Wait. He's just standing there. Where's the song? Danish: He's staring at me. Danish: This is a little creepy. Danish: What's going on? Danish: That's actually Rick Astley staring at me. Danish: What's he doing? Danish: Oh God, I keep expecting it, hearing it in my head. [Danish pulls at her hair.] Danish: Just do it already! [Danish runs off stage right.] Danish: Aaaaaaaa [Danish slams the door leaving Ponytail and Rick Astley] Door: Slam Ponytail: Mr. Astley? Rick Astley: Yes? Ponytail: What did you do to her? What was that? Rick Astley: That, my dear, [Rick Astley puts on sunglasses.] Rick Astley: Is how I roll.

This New Year comic plays out at what is, probably, a New Year party thrown by Danish . (The previous New Year day comic in 2007 was also related to a wild party: 364: Responsible Behavior ). In the first panel, we see Black Hat telling Cueball that he has hired Rick Astley to show up at a party for a girl. Cueball, assuming Rick Astley is going to perform a live rickroll, asks if that is not "so last year". Rickrolling is where one is redirected to a video of Rick Astley singing " Never Gonna Give You Up " via a weblink purporting to be something else. It was later extended to any situation where the song is used disruptively, such as during a party. It started in 2006 and grew until peaking on April Fool's Day in 2008. Thus at New Years Eve 2008, the meme was getting old. However, Black Hat assures Cueball that Rick Astley is not actually going to sing. The comic then continued to the now ongoing party and we see the girl in question, Danish , Black Hat's girlfriend, talking with Ponytail when she notices Rick Astley at her party. Like Cueball, Danish expects Rick Astley is going to sing and rickroll her live. She obviously hates this idea and braces her self for the humiliation of being rickrolled. But she is freaked out when he just stands there staring at her, but without singing. In the end his presence alone causes her to hear the song in her head instead, and finally she flees the room screaming slamming a door behind her. Black Hat has essentially rickrolled her in her own mind, which is far worse than just playing a song for her. But Black Hat could not have done so without the willing assistance from Rick! So when Ponytail asks Rick Astley "what did you do to her?", he begins by saying "that, my dear" and then slowly puts on sunglasses before he answers "Is how I roll." This references both rickrolling and the "that's how I roll" meme. Although the identity of the girl Black Hat is pranking is not stated by Randall (he refers to her as Girl 1 but he has also never given an official name to "Danish" - that is an explain xkcd name), she clearly is Danish, Black Hat's girlfriend. Danish was introduced in the Journal story-line ( 377: Journal 2 ), some time prior to this comic. At first her reaction may no look like Danish, who should play it cool according to the her first appearance! Black Hat, however, is a master and he could know that "not getting Rick rolled" would freak her even more out. Additionally, Danish is seen with Ponytail in 405: Journal 3 . And in that comic Black Hat also shows that he can get back at her, after she claimed she was better than him in 377: Journal 2 . He also tricks her into blowing her own garage up in 433: Journal 5 . So of course he can trick her, and of course she will hate that he has rick rolled her. So not doing it with Rick Astley in her house, would drive her mad, just like Black Hat would love, even if she is his girl friend. This would also not have happened for a normal girl like Megan , whom Danish slightly resembles. Normal people will laugh not cry after being rickrolled. The title text refers to the fact that rickrolling first appeared in 2007 (on 4chan ) and became viral for over a year. Giving that this is a New Year comic it is thus relevant to asks what meme will replace Rickrolling in the new year, 2009. Although Randall makes reference to the " Xzibit Yo Dawg " and " I accidentally... " photocaptioning memes, memebase entries suggest the "Keep Calm and Carry On" meme may well have become the most popular (and most enduring, as of 2013) meme of 2009. As of 2022, Rickrolling is still one of the most relevant memes from that era. [ citation needed ] Black Hat: And so I hired Rick Astley to show up at her party. Cueball: And rickroll her? Isn't that a little...last year? Black Hat: Ah, but he's not going to sing. Danish: Hey is that Rick Astley? Ponytail: I think it is. He just came in. Danish: Oh no. Brace yourself. Danish: Wait. He's just standing there. Where's the song? Danish: He's staring at me. Danish: This is a little creepy. Danish: What's going on? Danish: That's actually Rick Astley staring at me. Danish: What's he doing? Danish: Oh God, I keep expecting it, hearing it in my head. [Danish pulls at her hair.] Danish: Just do it already! [Danish runs off stage right.] Danish: Aaaaaaaa [Danish slams the door leaving Ponytail and Rick Astley] Door: Slam Ponytail: Mr. Astley? Rick Astley: Yes? Ponytail: What did you do to her? What was that? Rick Astley: That, my dear, [Rick Astley puts on sunglasses.] Rick Astley: Is how I roll.

I Know You're Listening

I Know You're Listening

https://www.xkcd.com/525

https://www.explainxkcd.com/wiki/index.php/525:_I_Know_You%27re_Listening

[Caption above the two panels of the comic:] Now and then, I announce "I know you're listening" to empty rooms. [Cueball is sitting in an armchair, reading. He murmurs something unreadable.] [A second Cueball-like surveillance man with headphones, seems to have gotten up from his office chair so fast that is has fallen over and lies behind him. He is now standing in front of a large computer terminal with two screens, he can hear Cueball's mumble as it is shown as coming from one of the screens. The surveillance man is leaning back away from the terminal while holding a hand to his headphones.] [Caption below the panels:] If I'm wrong, no one knows. And if I'm right, maybe I just freaked the hell out of some secret organization.

Cueball occasionally says "I know you're listening" aloud in empty rooms. The idea is, that if nobody is listening he doesn't lose anything, but if somebody is listening he gains by freaking them out. In this case another Cueball-like surveillance man does get quite the shock. As mentioned in the title text, this is similar to Pascal's Wager . Blaise Pascal was a French philosopher and mathematician who discussed the issue of the possibility that God actually does exist or not. According to Pascal, a rational person should live as though (a Christian) God exists, because he would lose negligible things if this turns out not to be true, but would gain immensely if it is true, by going to heaven in the afterlife. As Pascal himself recognized, this is not a proof of any god's existence, Christian or otherwise, but rather an inexorable choice made by every human being. Cueball makes a similar choice here, though hardly for such a moral reason. [Caption above the two panels of the comic:] Now and then, I announce "I know you're listening" to empty rooms. [Cueball is sitting in an armchair, reading. He murmurs something unreadable.] [A second Cueball-like surveillance man with headphones, seems to have gotten up from his office chair so fast that is has fallen over and lies behind him. He is now standing in front of a large computer terminal with two screens, he can hear Cueball's mumble as it is shown as coming from one of the screens. The surveillance man is leaning back away from the terminal while holding a hand to his headphones.] [Caption below the panels:] If I'm wrong, no one knows. And if I'm right, maybe I just freaked the hell out of some secret organization.

Converting to Metric

Converting to Metric

https://www.xkcd.com/526

https://www.explainxkcd.com/wiki/index.php/526:_Converting_to_Metric

Guide to Converting to Metric [There are five frames with tables for different units. Between the two upper frames is the following text:] The key to converting to metric is establishing new reference points. When you hear "26°C", instead of thinking "that's 79°F" you should think, "that's warmer than a house but cool for swimming." Here are some helpful tables of reference points: [The frame in the top left lists the following temperatures on the left, with the corresponding descriptions on the right. Next to the last three entries we see Cueball spitting on the ground. The spit freezes.] Temperature 60°C    Earth's hottest 45°C    Dubai heat wave 40°C    Southern US heat wave 35°C    Northern US heat wave 30°C    Beach weather 25°C    Warm room 20°C    Room temperature 10°C    Jacket weather 0°C      Snow! -5°C     Cold day (Boston) -10°C   Cold day (Moscow) -20°C   Fuckfuckfuckcold -30°C   Fuuuuuuuuuuck! -40°C   Spit goes "clink" Cueball: Ptoo Spit: Clink! [The frame in the top right lists the following lengths on the left, with their corresponding descriptions on the right. To the right of the table is a human tower of four of the people from the Serenity crew. The head of the upper person is right below the first entry.] Length 1 cm         Width of microSD card 3 cm         Length of SD card 12 cm       CD diameter 14 cm       Penis 15 cm       BIC pen 80 cm       Doorway width 1 m           Lightsaber blade 170 cm     Summer Glau 200 cm     Darth Vader 2.5 m        Ceiling 5 m           Car-length 16 m 4 cm Human tower of Serenity crew. [The frame in the bottom left has three columns] Speed kph   m/s 5      1.5    Walking 13    3.5    Jogging 25    7       Sprinting 35    10     Fastest human 45    13     Housecat 55    15     Rabbit 75    20     Raptor 100   25    Slow highway 110   30    Interstate (65 mph) 120   35    Speed you actually go when it says "65" 140   40    Raptor on hoverboard [The frame in the bottom middle lists the following volumes on the left, with their corresponding descriptions on the right. Volume 3 mL     Blood in a fieldmouse 5 mL     Teaspoon 30 mL    Nasal passages 40 mL    Shot glass 350 mL   Soda can 500 mL   Water bottle 3 L         Two-liter bottle 5 L          Blood in a human male 30 L        Milk crate 55 L        Summer Glau 65 L        Dennis Kucinich 75 L        Ron Paul 200 L      Fridge [Next to the entry on nasal passages and shot glass (starting one entry higher and finishing one entry lower) is the following text:] So, when it's blocked, the mucus in your nose could about fill a shot glass. [Below this text is a drawing of a mucus filled shot glass.] Related: I've invented the worst mixed drink ever. [Below this next to the four last entries we see Cueball shoving Summer Glau, Dennis Kucinich and Ron Paul into an open fridge. Above the fridge in a loosely drawn ellipse is the following text:] 55+65+75 < 200 [The frame in the bottom right lists the following masses on the left, with their corresponding descriptions on the right 3 g       Peanut M&M 100 g    Cell phone 500 g    Bottled water 1 kg      Ultraportable laptop 2 kg      Light-medium laptop 3 kg      Heavy laptop 5 kg      LCD monitor 15 kg     CRT monitor 4 kg       Cat 4.1 kg    Cat (with caption) 60 kg     Lady 70 kg     Dude 150 kg   Shaq 200 kg   Your mom 220 kg   Your mom (incl. cheap jewelry) 223 kg   Your mom (also incl. makeup) [Next to the entries of cat and cat (with caption) are two drawings of cats. The second one has a caption across its chest.] Cat (with caption): Mrowl? [Below this and next to the lady and dude entries are drawings of Megan and Cueball.]

Most people will eventually develop an intuitive feel for how big certain measurements are (e.g., how long an inch or a foot is, how much a pound weighs). This comic points out that people who were brought up using the United States system of customary units probably don't have the same intuitive understanding for metric units and attempts to provide some benchmarks for these people. Most of the benchmarks are common sense, highly-useful ones (e.g., if it's 30 degrees Celsius, you'd be quite comfortable outside dressed for the beach) but some of the benchmarks are humorous and/or completely useless as can be seen below. Some people argue for switching to metric units in the US, and these people became part of the comic 1982: Evangelism . In the book Thing Explainer a similar chart for metrics is shown in the explanation for How to count things , with four of the five measures from this comic also explained in simple language. Only volume is left out there. Only thing used in both explanations is the weight of a cat, but in the book it weighs 5 kg rather than 4 kg in this comic. See also 1643: Degrees about not being able to choose between the two temperature scales and 1923: Felsius about a compromise between the two scales. In the comic 1982: Evangelism , some people are stated to argue for the US to convert to the metric system, except for the Fahrenheit scale which they wish to keep. Here both the SI unit m/s as well as the more commonly used unit kph (km/h) is given. Note that the SI prefers "km/h" over the non-standard abbreviation "kph". The title text refers once again to Summer Glau's Firefly character, River Tam , who (after being subjected to a long series of medical experiments) is severely mentally ill and often comes out with macabre — though scientifically accurate — pronouncements. In Firefly episode "Safe" (season 1, episode 7), she says: "The human body can be drained of blood in 8.6 seconds given adequate vacuuming systems." The idea of the comic is to establish new metric reference points and not to resort to unit conversions. Nevertheless, the following table lists all units from the comic with their US customary equivalents: Guide to Converting to Metric [There are five frames with tables for different units. Between the two upper frames is the following text:] The key to converting to metric is establishing new reference points. When you hear "26°C", instead of thinking "that's 79°F" you should think, "that's warmer than a house but cool for swimming." Here are some helpful tables of reference points: [The frame in the top left lists the following temperatures on the left, with the corresponding descriptions on the right. Next to the last three entries we see Cueball spitting on the ground. The spit freezes.] Temperature 60°C    Earth's hottest 45°C    Dubai heat wave 40°C    Southern US heat wave 35°C    Northern US heat wave 30°C    Beach weather 25°C    Warm room 20°C    Room temperature 10°C    Jacket weather 0°C      Snow! -5°C     Cold day (Boston) -10°C   Cold day (Moscow) -20°C   Fuckfuckfuckcold -30°C   Fuuuuuuuuuuck! -40°C   Spit goes "clink" Cueball: Ptoo Spit: Clink! [The frame in the top right lists the following lengths on the left, with their corresponding descriptions on the right. To the right of the table is a human tower of four of the people from the Serenity crew. The head of the upper person is right below the first entry.] Length 1 cm         Width of microSD card 3 cm         Length of SD card 12 cm       CD diameter 14 cm       Penis 15 cm       BIC pen 80 cm       Doorway width 1 m           Lightsaber blade 170 cm     Summer Glau 200 cm     Darth Vader 2.5 m        Ceiling 5 m           Car-length 16 m 4 cm Human tower of Serenity crew. [The frame in the bottom left has three columns] Speed kph   m/s 5      1.5    Walking 13    3.5    Jogging 25    7       Sprinting 35    10     Fastest human 45    13     Housecat 55    15     Rabbit 75    20     Raptor 100   25    Slow highway 110   30    Interstate (65 mph) 120   35    Speed you actually go when it says "65" 140   40    Raptor on hoverboard [The frame in the bottom middle lists the following volumes on the left, with their corresponding descriptions on the right. Volume 3 mL     Blood in a fieldmouse 5 mL     Teaspoon 30 mL    Nasal passages 40 mL    Shot glass 350 mL   Soda can 500 mL   Water bottle 3 L         Two-liter bottle 5 L          Blood in a human male 30 L        Milk crate 55 L        Summer Glau 65 L        Dennis Kucinich 75 L        Ron Paul 200 L      Fridge [Next to the entry on nasal passages and shot glass (starting one entry higher and finishing one entry lower) is the following text:] So, when it's blocked, the mucus in your nose could about fill a shot glass. [Below this text is a drawing of a mucus filled shot glass.] Related: I've invented the worst mixed drink ever. [Below this next to the four last entries we see Cueball shoving Summer Glau, Dennis Kucinich and Ron Paul into an open fridge. Above the fridge in a loosely drawn ellipse is the following text:] 55+65+75 < 200 [The frame in the bottom right lists the following masses on the left, with their corresponding descriptions on the right 3 g       Peanut M&M 100 g    Cell phone 500 g    Bottled water 1 kg      Ultraportable laptop 2 kg      Light-medium laptop 3 kg      Heavy laptop 5 kg      LCD monitor 15 kg     CRT monitor 4 kg       Cat 4.1 kg    Cat (with caption) 60 kg     Lady 70 kg     Dude 150 kg   Shaq 200 kg   Your mom 220 kg   Your mom (incl. cheap jewelry) 223 kg   Your mom (also incl. makeup) [Next to the entries of cat and cat (with caption) are two drawings of cats. The second one has a caption across its chest.] Cat (with caption): Mrowl? [Below this and next to the lady and dude entries are drawings of Megan and Cueball.]

Keynote

Keynote

https://www.xkcd.com/527

https://www.explainxkcd.com/wiki/index.php/527:_Keynote

[Black Hat talking to Cueball sitting at computer.] Cueball: Huh - Steve Jobs isn't doing a keynote this year, citing massive weight loss due to some hormonal problem. Black Hat: Too bad. I bet Apple was excited about unveiling the thinnest and lightest CEO in the industry. Steve Jobs died on October 5, 2011 of pancreatic cancer the day before Randall released 961: Eternal Flame . Presumably, the cancer was the cause of Jobs' weight loss, although it was not public information at the time the comic was posted.

According to this comic, Steve Jobs , the founder of the Apple company, lost a lot of weight due to a hormonal problem. (Though never officially confirmed, this was likely related to Jobs's battle with pancreatic cancer, which he had been fighting for years and would frequently lead to speculation about his health at the time of this comic.) Black Hat then mentions that Apple was probably excited to announce its thinnest and lightest CEO in the industry. This comment is a parody of Apple's tendency to release thinner and lighter iterations of its products. Steve Jobs' weight loss would certainly make him a thinner and lighter CEO. The title text refers to Cory Doctorow , a blogger, journalist and science-fiction author. Doctorow is opposed to the technology called Digital restrictions management (DRM for short). DRM is designed to be abused by large corporations with negative consequences for consumers, but is disguised as a copyright protection system. Randall (jokingly) proposes that Steve Jobs is only sick because Doctorow was torturing him with Voodoo dolls for Apple's use of DRM. [Black Hat talking to Cueball sitting at computer.] Cueball: Huh - Steve Jobs isn't doing a keynote this year, citing massive weight loss due to some hormonal problem. Black Hat: Too bad. I bet Apple was excited about unveiling the thinnest and lightest CEO in the industry. Steve Jobs died on October 5, 2011 of pancreatic cancer the day before Randall released 961: Eternal Flame . Presumably, the cancer was the cause of Jobs' weight loss, although it was not public information at the time the comic was posted.

Windows 7

Windows 7

https://www.xkcd.com/528

https://www.explainxkcd.com/wiki/index.php/528:_Windows_7

[Megan is standing behind Cueball sitting at a desk using his laptop.] Megan: What are you doing? Cueball: Trying the Windows 7 beta. Megan: Why is it showing a picture of Hitler? [The laptop's screen is shown with Adolf Hitler's face on it, drawn in regular xkcd style with no facial features other than his hairstyle and mustache.] Cueball: I don't know. I can't get it to do anything else. Megan: There's no UI? Cueball: No, just Hitler. [Return to the original scene, except Megan is now scratching her head in confusion.] Megan: Did you try Ctrl-Alt-Delete? Cueball: It just makes Hitler's eyes flash. Megan: Huh. [Scene remains basically the same, except Megan is no longer scratching her head and Cueball is no longer typing on the laptop.] Megan: Well, it's better than Vista. Cueball: True.

This Comic came out 2 weeks after the beta version of the at that time not yet released Windows 7 got leaked on the internet, and 2 days after a trojan-infected version got leaked as well. Megan is observing Cueball use a laptop on which he has installed the Windows 7 beta. However, the alleged Windows 7 beta is showing nothing but a picture of Adolf Hitler and Cueball is unable to do anything. This could hint at the version containing malware. Cueball then presses Control-Alt-Delete (the well-known Windows Secure Attention Sequence which opens Task Manager or displays a list of options which includes 'Shut Down' and 'Restart') as suggested by Megan, but only manages to make the picture's eyes flash . The fourth panel shows Megan commenting that this Windows 7 beta is better than Windows Vista , to which Cueball agrees. The joke is that Megan deems a mostly non-functional and vaguely sinister OS, which is likely malware, better than Windows Vista, which was generally perceived as one of the worst Windows OSes. The title text is a disclaimer stating that Randall has not tried the beta at the time this comic was written, but what he has heard about it he regards as at least mildly positive. However, he also damns it by faint praise, referring to it as hardly Hitler-y at all, a statement that could raise warning flags, as one would not generally expect an operating system to be able to be described as Hitler-y to any degree at all. "Hitler-y" is implied to mean pertaining to or having qualities similar to Adolf Hitler, the late German Nazi Party leader and perhaps the most notorious mass-murderer in history. [Megan is standing behind Cueball sitting at a desk using his laptop.] Megan: What are you doing? Cueball: Trying the Windows 7 beta. Megan: Why is it showing a picture of Hitler? [The laptop's screen is shown with Adolf Hitler's face on it, drawn in regular xkcd style with no facial features other than his hairstyle and mustache.] Cueball: I don't know. I can't get it to do anything else. Megan: There's no UI? Cueball: No, just Hitler. [Return to the original scene, except Megan is now scratching her head in confusion.] Megan: Did you try Ctrl-Alt-Delete? Cueball: It just makes Hitler's eyes flash. Megan: Huh. [Scene remains basically the same, except Megan is no longer scratching her head and Cueball is no longer typing on the laptop.] Megan: Well, it's better than Vista. Cueball: True.

Sledding Discussion

Sledding Discussion

https://www.xkcd.com/529

https://www.explainxkcd.com/wiki/index.php/529:_Sledding_Discussion

[Megan looks out window through blinds.] Megan: It's snowing! Cueball: [from off-screen] Sled time! [Megan and Cueball outside with sled, at the top of a hill.] Cueball: It depresses me that I'm too old to learn another language fluently. My brain's solidified. [Megan and Cueball sledding down the hill.] Megan: Is there one you wish you knew? Cueball: No, I just hate having options closed to me. Like I've given up a life that was once possible. [At the bottom of the hill, sled has stopped.] Megan: Yeah. Which reminds me - our anniversary is coming up. Megan: Man, that ride failed to be a metaphor for our conversation. Cueball: Guess this isn't the Calvin & Hobbes-model toboggan.

Cueball and Megan have a perfectly normal sled ride down a perfectly normal hill (engaging in what's traditionally a children's pastime [ citation needed ] ) while Cueball is complaining that he has grown too old for certain things - like learning another language fluently (but not for taking a sleigh ride - although he does not really seem to enjoy it though). There is a hypothesis, called the critical period hypothesis , which states that you can only learn a language fluently before a certain age. Cueball hates that options are closed to him and feels like he has given up a life that was once possible . The joke is that this reminds Megan about their anniversary coming up. This means that she feels that she has given up a life that was once possible by staying so long with Cueball. Actually this may be the time when they are going to break up. The reader would thus have expected something ironic to happen at the end of the trip but instead, the only humor in the last frame arises from their commentary on the lack of humor . Calvin and Hobbes is an acclaimed newspaper comic strip that ran from 1985 to 1995. Calvin is a six-year-old child with an active imagination, and Hobbes is his stuffed tiger who Calvin perceives to be alive through his imagination. The two frequently had philosophical conversations, often while sledding . Calvin sledded on densely-wooded hills near where he lived, and the ride would often serve as a perfect parallel to the conversation they were having; for example, in one strip, Calvin talks about how seemingly mundane decisions can nonetheless have lasting consequences, by pointing out how all of the things they see as they continue down the hill (and eventually crash into a ravine) are a direct result of him having taken a particular fork early on. The title text notes that if you did have a Calvin and Hobbes toboggan , it would be the worst place to have a breaking-up conversation, perhaps because the sled itself would literally break-up during the journey, with potentially dangerous consequences. This is also the clue to the fact that the comic is in fact about a break-up situation. Calvin and Hobbes is also referenced in 409: Electric Skateboard (Double Comic) . [Megan looks out window through blinds.] Megan: It's snowing! Cueball: [from off-screen] Sled time! [Megan and Cueball outside with sled, at the top of a hill.] Cueball: It depresses me that I'm too old to learn another language fluently. My brain's solidified. [Megan and Cueball sledding down the hill.] Megan: Is there one you wish you knew? Cueball: No, I just hate having options closed to me. Like I've given up a life that was once possible. [At the bottom of the hill, sled has stopped.] Megan: Yeah. Which reminds me - our anniversary is coming up. Megan: Man, that ride failed to be a metaphor for our conversation. Cueball: Guess this isn't the Calvin & Hobbes-model toboggan.

I'm An Idiot

I'm An Idiot

https://www.xkcd.com/530

https://www.explainxkcd.com/wiki/index.php/530:_I%27m_An_Idiot

[Ponytail approaches Cueball, who is sitting on porch steps, laptop in lap and backpack open.] Ponytail: Should I ask? Cueball: I'm locked out, and I'm trying to get my roommate to let me in. [Unplugged cell phone on table.] Cueball: First I tried her cell phone, but it's off. [Cueball sitting on steps, laptop in lap and gesturing.] Cueball: Then I tried IRC, but she's not online. [Cueball standing in front of house and looking up at window.] Cueball: I couldn't find anything to throw at her window, [Living room with couch easy chair and computer set up.] Cueball: So I SSH'd into the Mac Mini in the living room and got the speech synth to yell at her for me. Computer: Hey I'm locked out downstairs [Megan sitting at table with laptop open.] Cueball: But I think I left the volume way down, so I'm reading the OS X docs to learn to set the volume via command line. [Ponytail facing Cueball, who is still sitting on the porch with his laptop.] Ponytail: Ah. Ponytail: I take it the doorbell doesn't work? [Beat panel.]

Cueball , locked out of his dorm / apartment , is trying to get his roommate Megan's attention so that she'll unlock the door. He tries various increasingly obscure ways of contacting her: calling her cell phone, IRC , the window, and finally remotely logging into their Mac computer (via SSH ) to make it shout at her, which involves working out a way to turn up the computer's volume. Ponytail informs him of the most obvious solution—the doorbell—which prompts a moment of realization. The content of this realization—"I'm An Idiot"—is stated in the title of the comic. The humor of the comic derives from the rhythm of the panels: a long buildup followed by a short quip, then a sudden, silent pause for the implied realization moment. Additionaly some readers will be familiar with the behavior shown in the comic, since most every person who likes solving problems has experienced a moment of realization similar to Cueball's at one point or another. They, like Cueball, get distracted by solving an interesting problem because solving problems is fun , and fail to notice that the problem has an easier solution that they haven't considered. This same issue of getting lost in a sub-problem [in this case, the-sub problem of how to remotely control text-to-speech in OS X] at the expense of overall problem-solving ability is further covered in 761: DFS . The title text states that this is a true story, so Cueball must represent Randall . It also mentions that, although missing an obvious solution can be humiliating, one often learns a lot from trying new solutions, which would explain why the behavior persists. This comic follows a similar storyline to 349: Success and 1518: Typical Morning Routine , as Cueball and Hairy respectively in these comics, encounters an issue and attempts proceedingly more absurd solutions to the issue. [Ponytail approaches Cueball, who is sitting on porch steps, laptop in lap and backpack open.] Ponytail: Should I ask? Cueball: I'm locked out, and I'm trying to get my roommate to let me in. [Unplugged cell phone on table.] Cueball: First I tried her cell phone, but it's off. [Cueball sitting on steps, laptop in lap and gesturing.] Cueball: Then I tried IRC, but she's not online. [Cueball standing in front of house and looking up at window.] Cueball: I couldn't find anything to throw at her window, [Living room with couch easy chair and computer set up.] Cueball: So I SSH'd into the Mac Mini in the living room and got the speech synth to yell at her for me. Computer: Hey I'm locked out downstairs [Megan sitting at table with laptop open.] Cueball: But I think I left the volume way down, so I'm reading the OS X docs to learn to set the volume via command line. [Ponytail facing Cueball, who is still sitting on the porch with his laptop.] Ponytail: Ah. Ponytail: I take it the doorbell doesn't work? [Beat panel.]

Contingency Plan

Contingency Plan

https://www.xkcd.com/531

https://www.explainxkcd.com/wiki/index.php/531:_Contingency_Plan

[Megan and Cueball holding a green bottle are standing beside a crib. Another green bottle is lying on the floor.] Megan: More sugary drinks? Are you trying to give her diabetes? Cueball: Yeah - then we keep her supplied with insulin unless things go wrong. [Caption below the frame:] I take the Jurassic Park approach to parenting.

Megan comments that Cueball is force-feeding their child so many sugary drinks that the child runs the risk of developing diabetes . Cueball responds that that is the plan, since if anything were to go wrong, they'll just have to stop giving her insulin , which will kill her. Cueball then comments that he thus takes the Jurassic Park approach to parenting. Jurassic Park is a series of books and films centering on a disastrous attempt to create a theme park of cloned dinosaurs. In particular, the park scientists give the dinosaurs lysine deficiency as a contingency plan , so that if some dinosaur were to escape, it wouldn't be able to survive in the wild. In practice, lysine can easily be obtained by eating protein-rich foods like red meat, lamb or pork. The title text continues the theme, noting that having children is basically one big genetic experiment, and that Cueball is experimenting responsibly, by having a contingency plan, thinking ahead as to the possible consequences of his experiment. The child interestingly cannot be seen in the crib. It may be that the sides of the crib are solid rather than barred like a traditional crib, or, more likely, Randall simply forgot to draw the child. [Megan and Cueball holding a green bottle are standing beside a crib. Another green bottle is lying on the floor.] Megan: More sugary drinks? Are you trying to give her diabetes? Cueball: Yeah - then we keep her supplied with insulin unless things go wrong. [Caption below the frame:] I take the Jurassic Park approach to parenting.

Piano

Piano

https://www.xkcd.com/532

https://www.explainxkcd.com/wiki/index.php/532:_Piano

[Cueball is holding a box with an open lid. A miniature piano is inside. Megan is looking at it] Cueball: My hobby is making miniatures. Check this out — it's a fully-functional grand piano. Megan: Woah — beautiful. [Cueball looks at the miniature piano.] Cueball: Sadly, I've never heard what proper music sounds like on it—the keys are too small to play. [Cueball closes lid to the piano.] Cueball: I once asked a genie for someone who could play it for me, but I think he misheard. Megan: ...are you doing anything later? For the record, pianist /'piənɪst/ and penis /'pinɪs/ are near homophones in English. This is because pianist has a different stress pattern than piano /pi'æno/. The vagaries of the English language.

This comic is the reverse of the "twelve inch pianist" joke that appeared in the rec.humor.funny Usenet newsgroup . In the original joke, a man found a genie in a bottle, and it is implied that he wished for a "twelve inch penis ," but the genie misheard him and instead granted him a "twelve inch pianist ." The crux is that the word pianist sounds similar to the word penis ; the joke also relies on the common trope of genies granting wishes (as in the tale of Aladdin and the Wonderful Lamp ), sometimes with creative (mis)understanding or literalism as an Aesop to be wary about what you wish for, as well as the common stereotype that larger penises are more desirable. In this comic, the opposite happens: Cueball wished for a "twelve inch pianist " to play his miniature piano, but was misheard by the genie, implying that the genie instead granted him a "twelve inch penis ." Megan has understood this implication, and therefore wants to have sex with Cueball (in accordance with the aforementioned stereotype). The title text suggests that if Cueball had made a smaller piano – and had thus wished for a smaller pianist – he would have instead received a smaller penis , making him less desirable according to the stereotype. Genies (or the magic lamps containing them) are mentioned in at least four other comics: [Cueball is holding a box with an open lid. A miniature piano is inside. Megan is looking at it] Cueball: My hobby is making miniatures. Check this out — it's a fully-functional grand piano. Megan: Woah — beautiful. [Cueball looks at the miniature piano.] Cueball: Sadly, I've never heard what proper music sounds like on it—the keys are too small to play. [Cueball closes lid to the piano.] Cueball: I once asked a genie for someone who could play it for me, but I think he misheard. Megan: ...are you doing anything later? For the record, pianist /'piənɪst/ and penis /'pinɪs/ are near homophones in English. This is because pianist has a different stress pattern than piano /pi'æno/. The vagaries of the English language.

Laptop Hell

Laptop Hell

https://www.xkcd.com/533

https://www.explainxkcd.com/wiki/index.php/533:_Laptop_Hell

[A devil, Mephistopheles (according to the official transcript ), with bald head horns, tail with arrow ending, a trident in one hand and a paper in the other hand is ready to welcome Hairbun to hell. Above Mephistopheles there are three large stalactite hanging down and behind Hairbun there is one very large stalagmite and three small and also two small stalactites.] Mephistopheles: Welcome to Hell. Here's— Mephistopheles:Wait. I know you. [Zoom in on the two, with white background. Mephistopheles trident breaks the panels frame.] Mephistopheles: You're the Fujitsu exec who killed the Q-series. Hairbun: ...Yes? Mephistopheles: The Q2010 was the perfect laptop! [In this frame-less panel with white background Mephistopheles walks away from Hairbun trident pointing up and left. Hairbun throws her arms out to the side.] Mephistopheles: Powerful, durable, had every feature, and made the Air look bulky . And that was back in 2006! Hairbun: But no one bought it! Mephistopheles: Then you marketed it wrong! [Mephistopheles turns around towards Hairbun who both standing as in the first panel but still with white background.] Hairbun: Wait. Don't you encourage evil acts down here? Mephistopheles: In theory, yes, but we need laptops too! Mephistopheles: Although it's moot, since we have an exclusive deal with Sony. Hairbun: I knew it!

The Devil Mephistopheles (named so in the official transcript ) is greeting the new souls sentenced to Hell , and recognizes an executive from Fujitsu Ltd in the form of Hairbun . Mephistopheles accuses her of causing his favorite laptop, the Fujitsu Q2010, to be taken out of production. Mephistopheles is displeased because he thought it was a good laptop, just poorly marketed by Hairbun. Hairbun is confused and asks Mephistopheles why he is upset, as acts of evil are generally encouraged by the demons of Hell. Mephistopheles agrees but explains that Hell also needs good laptops, and in her case their need for laptops was greater than the need for her evil works. Though, Mephistopheles then goes on to confess, that it would not really have mattered as Hell has an exclusive deal with Fujitsu competitor, Sony , and he could not have bought the Fujitsu Q2010 anyway. This would explain why the sale of the laptop failed, and Hairbun also exclaims I knew it to indicate that she had suspected it was weird that Sony did so well. When one strikes a deal with a devil from Hell, their affairs in life go great, but of course one has then sentenced their soul to eternal damnation in Hell when one eventually dies. [ citation needed ] Seems like Sony has done so according to this comic. This comic is likely a wish fulfillment fantasy by Randall for the canceling of his favorite laptop, the Fujitsu Q2010. Exclusivity deals are typically thought ill of as they are bad for competition. Also, since exclusivity deals solely benefit the provider, there are often reciprocal arrangements for the purchaser. This implies that the devil has influence at Sony. Likely, Sony was chosen as the electronic distributor to Hell because of the Sony rootkit scandal . This scandal inspired many to call Sony an evil company. It is the second time in a short while that a demon was depicted in a similar fashion although without the trident and not in Hell. This devil was also named Mephistopheles in the caption of that comic 501: Faust 2.0 . The title text explains that Randall's system administrator is upset with him because he tested the system administrator's laptop by throwing it down several flights of steps. The systems admin is implied to have taken revenge childishly, by replacing part of the text with "DISREGARD THAT I SUCK COCKS" although it was almost certainly done by Randall as a joke. The "suck cocks" part is a reference to a post in bash.org which went on to attain moderate fame. [A devil, Mephistopheles (according to the official transcript ), with bald head horns, tail with arrow ending, a trident in one hand and a paper in the other hand is ready to welcome Hairbun to hell. Above Mephistopheles there are three large stalactite hanging down and behind Hairbun there is one very large stalagmite and three small and also two small stalactites.] Mephistopheles: Welcome to Hell. Here's— Mephistopheles:Wait. I know you. [Zoom in on the two, with white background. Mephistopheles trident breaks the panels frame.] Mephistopheles: You're the Fujitsu exec who killed the Q-series. Hairbun: ...Yes? Mephistopheles: The Q2010 was the perfect laptop! [In this frame-less panel with white background Mephistopheles walks away from Hairbun trident pointing up and left. Hairbun throws her arms out to the side.] Mephistopheles: Powerful, durable, had every feature, and made the Air look bulky . And that was back in 2006! Hairbun: But no one bought it! Mephistopheles: Then you marketed it wrong! [Mephistopheles turns around towards Hairbun who both standing as in the first panel but still with white background.] Hairbun: Wait. Don't you encourage evil acts down here? Mephistopheles: In theory, yes, but we need laptops too! Mephistopheles: Although it's moot, since we have an exclusive deal with Sony. Hairbun: I knew it!

Genetic Algorithms

Genetic Algorithms

https://www.xkcd.com/534

https://www.explainxkcd.com/wiki/index.php/534:_Genetic_Algorithms

[Code displayed, presumably from an IDE.] def getSolutionCosts(navigationCode): fuelStopCost = 15 extraComputationCost = 8 [There is a giant arrow pointing to the next line.] thisAlgorithmBecomingSkynetCost = 999999999 waterCrossingCost = 45 Genetic algorithms tip: Always include this in your fitness function.

In the computer science field of artificial intelligence , a genetic algorithm is a search heuristic that mimics the process of natural evolution . This heuristic is routinely used to generate useful solutions to optimization and search problems. Genetic algorithms belong to the larger class of evolutionary algorithms, which generate solutions to optimization problems using techniques inspired by natural evolution, such as inheritance, mutation, selection, and crossover. In particular, genetic algorithms are designed to evolve, with various mechanisms being used to mimic natural selection. One such mechanism is to assign "costs" to various aspects of the program, and to select for programs which assess a fitness function such as calculating the least sum of all these costs (thus mimicking organisms in an environment where they have to compete for limited resources) versus any measurable benefits. The line indicated by an arrow is a reference to the Terminator series, in which the main antagonist is an artificial intelligence known as Skynet that seeks to destroy all humans. By setting an absurdly high cost for an algorithm transforming into Skynet, the coder makes a preventive measure against the algorithm achieving such sentience. The line about water crossing is a possible reference to the old computer game The Oregon Trail , in which crossing water was hazardous. This video game was referenced again in 623: Oregon . The title text refers to the method by which the program select the desired option, with minimizing being where the program seeks the lowest possible number, and maximizing where the program seeks the highest possible number. When dealing with cases such as generating profit, maximization would obviously be preferred over minimization; but selecting maximization here would be disastrous as it would always chose the BecomingSkynet option before any other due to its massive cost. [Code displayed, presumably from an IDE.] def getSolutionCosts(navigationCode): fuelStopCost = 15 extraComputationCost = 8 [There is a giant arrow pointing to the next line.] thisAlgorithmBecomingSkynetCost = 999999999 waterCrossingCost = 45 Genetic algorithms tip: Always include this in your fitness function.

It Might Be Cool

It Might Be Cool

https://www.xkcd.com/535

https://www.explainxkcd.com/wiki/index.php/535:_It_Might_Be_Cool

[Cueball is administering the presidential oath with the coming president also drawn as Cueball.] Cueball: You know, it might be cool to be a woman. President: It... might be cool to be a woman? Cueball: Yeah, but the menstruation thing is freaky. President: Yeah, but... the... um. What? [Caption below the frame:] Turns out I'm even worse at administering the presidential oath than John Roberts.

Cueball (or Randall ) is musing about the possibility of being a woman, to the confusion of the man next to him. His uninsightful rambling would likely be unimpressive and somewhat odd in most situations, but not odd enough on its own to prompt the second man's baffled reaction. However, the true reason for his confusion is revealed by the caption: Cueball is administering the presidential oath . The oath is administered by reciting it to prompt a new president to repeat them back to him. However, he botches it completely by forgetting about his task completely and wondering aloud about an unrelated topic. Thus, the president's confused question at the beginning is not him asking for clarification; he is repeating what he at first believed to be the oath of office, but got flustered when he realized Cueball had deviated from the script. When Cueball then continues by replying that "the menstruation thing is freaky," the president is completely derailed. On January 20, 2009 the inauguration of Barack Obama 's first office took place. Chief Justice John Roberts , who was administering the oath, made a mistake while reciting the words. This comic references the event and wildly exaggerates the deviation from the oath for comedic purposes. In truth, the error was rather small: the oath as prescribed in the constitution is: I do solemnly swear that I will faithfully execute the office of President of the United States and will to the best of my ability preserve, protect, and defend the Constitution of the United States. Due to a missed memo on the pauses planned by the Chief Justice, Obama inadvertently interrupted Roberts during the first phrase - Roberts begins by saying I, Barack Obama, do solemnly swear, and Obama repeats his name while Roberts finishes that sentence. This disturbs Roberts who was not using notes, and he rendered the next phrase as "that I will execute the office of president to the United States faithfully," misplacing the word faithfully and saying president to instead of president of . Obama repeated, "that I will execute", then paused. Roberts attempted to correct the wording, but stumbled: "the off— faithfully the pres— the office of President of the United States." Obama then repeated Roberts' initial incorrect wording. However small the error was it was big enough that Obama did retake the oath of office the day after the mistake was made. The title text continues the wondering about being a woman going on from the menstruation to the ovaries . To make sure it is clearly the oath mistake that is referenced the sentence ends with '... faithfully.' Thus mimicking the real mistake of placing this word last. Cueball might be an egg , an individual who is transgender and unaware of such. [Cueball is administering the presidential oath with the coming president also drawn as Cueball.] Cueball: You know, it might be cool to be a woman. President: It... might be cool to be a woman? Cueball: Yeah, but the menstruation thing is freaky. President: Yeah, but... the... um. What? [Caption below the frame:] Turns out I'm even worse at administering the presidential oath than John Roberts.

Space Elevators

Space Elevators

https://www.xkcd.com/536

https://www.explainxkcd.com/wiki/index.php/536:_Space_Elevators

[Cueball and Megan sit beside a moonlit lake.] Cueball: Arthur C. Clarke said space elevators will be built 50 years after everybody stops laughing. [Closeup of Cueball.] Cueball: So all we have to do is get Mind of Mencia on every channel and wait. Megan (offscreen): Oh, hush.

Arthur C. Clarke was a science fiction writer and a futurist. The quoted remark provides a benchmark for how long it will take to create something as massive and advanced as a space elevator : when technology reaches the point where the idea is considered seriously rather than dismissed out of hand, about fifty years of further effort will make it a reality. Mind of Mencia was an American television comedy series running from 2005 to 2008. Cueball implies that the show is so unfunny that putting it on every channel would destroy everyone's sense of humor , thus preventing them from laughing at anything, space elevators included. Cueball is missing the point of Clarke's quote; Clarke was referring to people no longer laughing at the idea of a space elevator, not people no longer laughing entirely. The space fountain , mentioned in the title text, is another proposed method of overcoming the planet's gravitational barrier, involving an effect similar to that of a coil gun . [Cueball and Megan sit beside a moonlit lake.] Cueball: Arthur C. Clarke said space elevators will be built 50 years after everybody stops laughing. [Closeup of Cueball.] Cueball: So all we have to do is get Mind of Mencia on every channel and wait. Megan (offscreen): Oh, hush.

Ducklings

Ducklings

https://www.xkcd.com/537

https://www.explainxkcd.com/wiki/index.php/537:_Ducklings

[A mother duck and her six ducklings.] [Cueball is in front of the line of ducks, and Megan is behind.] Megan: Ready? Cueball: Ready. [The duck and ducklings move.] Cueball: ROAR! BOO! [The mother duck is frightened, and turns back. Her six children follow.] [Megan snatches the mother duck with a yoink.] Duck: QUACK! [The six ducklings are now trapped in a circle of sorts.] OPERATION: DUCKLING LOOP

The comic shows an elaborate plan. The mother and her ducklings will always walk in a line. The ducklings will either follow their mother, or the duckling in front of them. Cueball scares the mother duck, so she starts running away, her children following her in a line. Then Megan snatches the mother duck, leaving the first duckling to start following the last duckling, causing the ducklings to walk in a loop. Hence the caption at the end - "Operation: Duckling Loop." However, eventually the ducklings will probably realize something has gone wrong, [ citation needed ] and break the loop. This behavior occurs naturally in real life with creatures that are less smart than ducks, such as sheep and ants (the phenomenon is called an ant mill ). The title text refers to a meme called "Duckrolled", where one would post a link to a picture of a duck on wheels. It became much more famous in its later incarnation as the Rickroll . [A mother duck and her six ducklings.] [Cueball is in front of the line of ducks, and Megan is behind.] Megan: Ready? Cueball: Ready. [The duck and ducklings move.] Cueball: ROAR! BOO! [The mother duck is frightened, and turns back. Her six children follow.] [Megan snatches the mother duck with a yoink.] Duck: QUACK! [The six ducklings are now trapped in a circle of sorts.] OPERATION: DUCKLING LOOP

Security

Security

https://www.xkcd.com/538

https://www.explainxkcd.com/wiki/index.php/538:_Security

[Cueball is holding a laptop up in two hands, showing it to his Cueball-like friend who is examining it while holding a hand up to his head. Above the top of the panels frame, there is a box with a caption:] A Crypto nerd's imagination: Cueball: His laptop's encrypted. Let's build a million-dollar cluster to crack it. Friend: No good! It's 4096-bit RSA! Cueball: Blast! Our evil plan is foiled! [Cueball is holding a a closed laptop down in one hand while giving his Cueball-like friend a wrench with the other. The friend reaches out for it. Above the top of the panels frame, there is a box with a caption:] What would actually happen: Cueball: His laptop's encrypted. Drug him and hit him with this $5 wrench until he tells us the password. Friend : Got it.

The "crypto nerd" would be concerned with strongly encrypting data on their personal machine. This would conceivably come in handy when "villains" attempt to steal information on his computer. The crypto nerd imagines that due to his advanced encryption, the crackers will be ultimately defeated. Randall suggests that in the real world, people with the desire to access this information would simply use torture to coerce the nerd to give them the password. Both panels also reference the amount of money used to access the data. In the first the villain is willing to use millions of dollars to construct a super computer which may still not fulfill their aim, while in the second, he simply uses a $5 wrench and 'the personal touch'. The comic effectively states, completely accurately, that the weakest part of computer security is usually not the computer, but the user. RSA is a commonly used public key encryption method. Current standards typically use 1024, 2048, and (more recently) 4096 bit keys . These encryption methods are not yet (feasibly) breakable. A 4096-bit key will remain unbreakable for the foreseeable future. To be resilient against this sort of "attack", cryptographers have devised schemes of deniable encryption , where attackers either cannot prove that encrypted information exists at all, or that allows the user to provide a password that reveals one (innocuous, or embarrassing but not illegal) secret without giving any indication that there is a second password that reveals the more important secret. The title text pokes fun at typical users, who do not have data that would be worth anything to anyone but themselves. Therefore, it is unlikely that the above situation would ever occur. Additionally, the wrench used in the second panel is large, and presumably more than the $5 referenced by the thug. [Cueball is holding a laptop up in two hands, showing it to his Cueball-like friend who is examining it while holding a hand up to his head. Above the top of the panels frame, there is a box with a caption:] A Crypto nerd's imagination: Cueball: His laptop's encrypted. Let's build a million-dollar cluster to crack it. Friend: No good! It's 4096-bit RSA! Cueball: Blast! Our evil plan is foiled! [Cueball is holding a a closed laptop down in one hand while giving his Cueball-like friend a wrench with the other. The friend reaches out for it. Above the top of the panels frame, there is a box with a caption:] What would actually happen: Cueball: His laptop's encrypted. Drug him and hit him with this $5 wrench until he tells us the password. Friend : Got it.

Boyfriend

Boyfriend

https://www.xkcd.com/539

https://www.explainxkcd.com/wiki/index.php/539:_Boyfriend

[Megan is on the phone.] Megan: Can my boyfriend come along? [Cueball talks to Megan.] Cueball: I'm not your boyfriend! Megan: You totally are. Cueball: I'm casually dating a number of people. [Megan points to a chart with gray box plot with a single black dot as an outlier to the far right.] Megan: But you spend twice as much time with me as with anyone else. I'm a clear outlier. [Cueball puts his hand on his chin while Megan spreads out her arms.] Cueball: Your math is irrefutable. Megan: Face it—I'm your statistically significant other.

In classical statistics, statistical significance is used to determine whether a conclusion can be confidently made about the implications of a given set of data. If some data set is determined to be an appropriate sample of a given population, then conclusions can be made by determining trends in the data. Since one can never be completely sure that their data is truly representative, or their statistical analysis completely accurate, calculations of the likelihood of error are made. Once these calculations are made, it can be decided that a given conclusion is statistically significant because it passes a certain threshold for the likelihood of error. Because the statistical analysis that was done concluded that it is significantly more likely that the conclusions made are accurate than inaccurate, these conclusions are termed statistically significant. In this case, Megan has analyzed the amount of time that Cueball spends with her versus others in his life. Based on the data she has gathered, she constructed a box plot. A box plot is a way to present data that utilizes boxes to show the range that a certain percentage of data points fall into. The boxes denote quartiles, so the large box demonstrates the range between the lowest and highest quartile, and the line in the center of the box denotes the median of the entire data set. The bars extend to the outer limits of the data set, encompassing the highest and lowest points (but excluding outliers). Box plots are useful to show the spread of data, and how it may be skewed. For more on box plots, see Box plot . Megan uses the data she has collected to show that the amount of time that Cueball spends with her is significantly higher than the amount of time he spends with others, since the amount of time they spend together is high enough to be an outlier when she completes a statistical analysis of the time he spends with people in his life. Cueball accepts her claim, and she responds with a witticism that combines the phrases "statistically significant" and "significant other". The title text can be interpreted in multiple ways. Firstly, Cueball may be resistant to the title of boyfriend . As he indicates, he is currently casually dating multiple people, and may therefore be resistant to any single individual attempting to establish a monogamous relationship. It could also be inferred that anyone taking the time and effort to statistically examine their relationship with him is off-putting, as this behavior could be viewed as obsessive. It could also be theorized that the term statistically significant other seems cold, and Cueball would rather date someone who makes him feel as though their relationship is significant, not simply someone who is an outlier in terms of time spent together. However, we know how Cueball responds to graphs without axes , so part of his rejection may stem from his disdain of her graph's lack of necessary units (for all we know, he could be spending significantly less time with Megan than with others! ...Or it could just be that it's a cringe-worthy pun, and Cueball doesn't appreciate Megan being so pun-happy. The unduly [ citation needed ] severe consequences for an over-elaborate pun setup are analogous to how another Cueball gets his math license revoked over a pun. [Megan is on the phone.] Megan: Can my boyfriend come along? [Cueball talks to Megan.] Cueball: I'm not your boyfriend! Megan: You totally are. Cueball: I'm casually dating a number of people. [Megan points to a chart with gray box plot with a single black dot as an outlier to the far right.] Megan: But you spend twice as much time with me as with anyone else. I'm a clear outlier. [Cueball puts his hand on his chin while Megan spreads out her arms.] Cueball: Your math is irrefutable. Megan: Face it—I'm your statistically significant other.

Base System

Base System

https://www.xkcd.com/540

https://www.explainxkcd.com/wiki/index.php/540:_Base_System

[At the top there is a four panel regular comic strip.] [Cueball and Ponytail are talking; Ponytail is sitting on the back of a chair with her feet on the seat, and Cueball is sitting on the floor facing her.] Ponytail: So how far did you get with her? Cueball: Second base? [Zoom in on Ponytail on the chair.] Ponytail: Wait, which one is that? Below the waist, but... not under the clothes? Cueball (off-panel): I think that's... shortstop? [In a frameless panel, Cueball now almost lies down and Ponytail is sitting on the armrest of the chair.] Ponytail: You should try crossing the pitcher's mound. Then down the 50-yard line, and right past her ten-pin. Cueball: Sounds tricky. [Again a zoom in on Ponytail now on the armrest.] Ponytail: Yeah. Last time I tried it, I got a red flag. If you know what I mean. Cueball (off-panel): I really don't. [Below the strip there is a large frame with a diagram of a baseball diamond.] [At the bottom left there is a box with tis text:] The "Base" Metaphor Explained [Bases are pointed too with thick black arrows (except home plate) and there are also arrows pointing to different parts of the diagram. All arrows and points marked with "x" have a description, as do the dashed lines covering the field. Below they will be listed anti-clockwise from the home plate.] [Along the line towards first base is the following five items in the order they appear:] [x slightly right of home plate:] Eye contact [Black arrow pointing to a base half way to first base outside the line:] Your Base [x inside the line opposite your base] Passing notes [Black arrow pointing to a base further along and outside the line:] 0110 0010 0110 0001 0111 0011 0110 0101 0010 0000 0011 0010 [x Slightly before first base:] Downloading Star Trek fanfiction and replacing Riker's name with your crush's. [Black arrow pointing to first base:] First base: Kissing [Further along the line past the first base is one x point in the right outfield:] Eye contact from Janeane Garofalo. [On the way towards second base there are the following two items:] [A region along the line from first to second has been marked off by a dotted line. It has the following text written inside:] The boring zone. [x some way inside the line next to the boring zone:] Using the scroll thingy on that one Apple mouse [Black arrow pointing to second base:] Second base: Hands under the shirt and/or licking [On the route from second to third base are eight items:] [A dotted line traveling from near the outfield above second base, then crossing the second baseline about 1/3 of the way to third base, snaking its way almost down to the home plate ending close to the third baseline. The following text is written along the dotted line inside the diamond:] The orgasm line [Above second base a large black arrow crosses the orgasm line near the outfield:] Napoleon's forces [x below the Napoleon arrow right before crossing the orgasm line:] Fursuits [Two arrows points to the second base line on each side of the orgasm line:] Hands on the pants Hands in the pants [x some way into the diamond just past the orgasm line:] Dry humping [x same distance down the second base line as dry humping, but equally far outside the line still infield:] Fursuits (crotchless) [x almost at the extension of the 3rd base line close to the outfield:] Standing anywhere near Peaches [In the left outfield there are two x points:] [x in the outfield halfway along the second base line:] Retrograde wheelbarrow [x in the outfield almost at the extension of the third base line:] 2outfielders1glove. [Foul of the third base line just left of where the grass line divides the in- and outfield:] Anal sex (fill in your own "foul ball" pun here.) [Black arrow pointing to third base:] Third base: Oral sex (formerly "hands in the pants") [On the route from third to home plate there are four items:] [Between third base and home there is a dotted line that makes a curve from right outside the third base line and ends right afer it has crossed the orgasm line. The text is written inside the diamond with the first word above and the other two below the dotted line:] "Virginity" (Maginot) line [A large black arrow curves around the end of the "Virginity" line outside of the diamond:] Teens [A large black arrow points from outside the diamond to a point right between home plate and the virginity line:] Sharing root PWs [x just before home plate at the end of the orgasm line inside the diamond:] Thigh contact

This comic comes in two parts and is a pun on the baseball metaphor used to describe how far a date went regarding erotic actions. Many different versions of the baseball metaphor exist, with varying degrees of complexity. But it has rarely been described with as many details as the one drawn by Randall in this comic. In the first part, a four frame strip along the top, Ponytail and Cueball discuss how Cueball's date went. When Cueball answers Ponytail's question with "second base", Ponytail asks what that means exactly. They fumble around with the definition in panel two where Ponytail ask is that Below the waist, but... not under the clothes? Cueball tries to put this into the base system and suggest that this could be compared to the difficult shortstop fielding position in baseball, between 2nd and 3rd base. This fits with the position of Hands on the pants metaphor from the picture below the comic strip. Then Ponytail begins with yet another base analogy by mentioning crossing the pitcher's mound , but then suddenly she brings two more, very different, sports into the metaphor: American football (with the 50 yard line) and bowling (with the ten-pin ). It certainly sounds tricky, as Cueball says. Ponytail then brings up a third sport in her elaboration; her reference to getting a "red flag" could refer to different sports, as many sports use flags , some of them red. It is, however, most likely a reference to racing in motor sport as the red flag is displayed when conditions are too dangerous to continue the session. This makes sense when looking at the "translation" here below. Cueball, however, has not got a clue which he expresses when Ponytail asks him If you know what I mean. (Note that this comic came out less than a week after Super Bowl XLIII , the final game of the 2008 NFL season , which was played on 2009-02-01). Here is a possible translation of Ponytails comment: Original: You should try crossing the pitcher's mound . Then down the 50-yard line , and right past her ten-pin . Translation: You should try crossing her pubic mound , then down the landing strip , and right past her clitoris . Original: Last time I tried it, I got a red flag . Translation: Last time I tried it, she had her period . This would mean that Ponytail was about to go down on another girl, while this girl had her period. Many people would find it disgusting to go down on a girl while she was menstruating, explaining why Ponytail brought it up when Cueball said Sounds tricky . However, Cueball doesn't seem to understand Ponytail's metaphors, explaining his replies of Sounds tricky and I really don't . The second part, the diagram, depicts a much more complex version of the baseball metaphor, where baseball terms and jargon are used to describe the many and varied things human beings like to do in the bedroom. Explanations have been separated by position. In order to understand the terms used, one may want to consult this picture: Note that Randall did not include any features from within the diamond; the pitchers mound or plate. The " diamond " is the geometric pattern formed by the four bases - first, second, third, and home plate . Through the course of one side's turn (half of an "inning") players have a chance to move from one base to the next base in line: from first, to second, to third, and finally to home plate (scoring only if they make it to home plate). Thus there is a "progression" from one base to the next of sexual activity in the metaphor, until climax is achieved (getting to 'home plate' and 'scoring a run'). In both cases, players can be removed before making it to the next "base" in the sequence. The entries in this section are ordered roughly from home plate to first, to second, to third, and then to home plate again, in the counterclockwise direction that the players move. Inside the diamond, at the center of the mound, is the pitcher. Several odd positions are placed here in Randall's diagram. The infield is the part of the baseball field which is inside the baserunning paths (not inside the lines between the bases, because baserunners are allowed to run a certain distance outside those lines). The " outfield " is a group of players who are there to catch the ball if it goes away from the main play area (anything outside the upper curving line) and return it to play in a manner advantageous to their team. As they separated away from the main play area, the things in the outfield are often references to sexual behaviors that are "kinky" and "out there". A foul ball occurs when a ball ends up in foul territory which is outside the foul line extending from either side of the diamond, the area is "out of play". Anyone who takes the ball into this area has committed a foul, and as such breached one of the acceptable rules of sexual conduct in the metaphor. If you are together with a basketball player and then tell her that you are now at second base , she might become very confused as bases are not an element in basketball. Also there is the joke that basketball players never get laid because they always jump before they score. [At the top there is a four panel regular comic strip.] [Cueball and Ponytail are talking; Ponytail is sitting on the back of a chair with her feet on the seat, and Cueball is sitting on the floor facing her.] Ponytail: So how far did you get with her? Cueball: Second base? [Zoom in on Ponytail on the chair.] Ponytail: Wait, which one is that? Below the waist, but... not under the clothes? Cueball (off-panel): I think that's... shortstop? [In a frameless panel, Cueball now almost lies down and Ponytail is sitting on the armrest of the chair.] Ponytail: You should try crossing the pitcher's mound. Then down the 50-yard line, and right past her ten-pin. Cueball: Sounds tricky. [Again a zoom in on Ponytail now on the armrest.] Ponytail: Yeah. Last time I tried it, I got a red flag. If you know what I mean. Cueball (off-panel): I really don't. [Below the strip there is a large frame with a diagram of a baseball diamond.] [At the bottom left there is a box with tis text:] The "Base" Metaphor Explained [Bases are pointed too with thick black arrows (except home plate) and there are also arrows pointing to different parts of the diagram. All arrows and points marked with "x" have a description, as do the dashed lines covering the field. Below they will be listed anti-clockwise from the home plate.] [Along the line towards first base is the following five items in the order they appear:] [x slightly right of home plate:] Eye contact [Black arrow pointing to a base half way to first base outside the line:] Your Base [x inside the line opposite your base] Passing notes [Black arrow pointing to a base further along and outside the line:] 0110 0010 0110 0001 0111 0011 0110 0101 0010 0000 0011 0010 [x Slightly before first base:] Downloading Star Trek fanfiction and replacing Riker's name with your crush's. [Black arrow pointing to first base:] First base: Kissing [Further along the line past the first base is one x point in the right outfield:] Eye contact from Janeane Garofalo. [On the way towards second base there are the following two items:] [A region along the line from first to second has been marked off by a dotted line. It has the following text written inside:] The boring zone. [x some way inside the line next to the boring zone:] Using the scroll thingy on that one Apple mouse [Black arrow pointing to second base:] Second base: Hands under the shirt and/or licking [On the route from second to third base are eight items:] [A dotted line traveling from near the outfield above second base, then crossing the second baseline about 1/3 of the way to third base, snaking its way almost down to the home plate ending close to the third baseline. The following text is written along the dotted line inside the diamond:] The orgasm line [Above second base a large black arrow crosses the orgasm line near the outfield:] Napoleon's forces [x below the Napoleon arrow right before crossing the orgasm line:] Fursuits [Two arrows points to the second base line on each side of the orgasm line:] Hands on the pants Hands in the pants [x some way into the diamond just past the orgasm line:] Dry humping [x same distance down the second base line as dry humping, but equally far outside the line still infield:] Fursuits (crotchless) [x almost at the extension of the 3rd base line close to the outfield:] Standing anywhere near Peaches [In the left outfield there are two x points:] [x in the outfield halfway along the second base line:] Retrograde wheelbarrow [x in the outfield almost at the extension of the third base line:] 2outfielders1glove. [Foul of the third base line just left of where the grass line divides the in- and outfield:] Anal sex (fill in your own "foul ball" pun here.) [Black arrow pointing to third base:] Third base: Oral sex (formerly "hands in the pants") [On the route from third to home plate there are four items:] [Between third base and home there is a dotted line that makes a curve from right outside the third base line and ends right afer it has crossed the orgasm line. The text is written inside the diamond with the first word above and the other two below the dotted line:] "Virginity" (Maginot) line [A large black arrow curves around the end of the "Virginity" line outside of the diamond:] Teens [A large black arrow points from outside the diamond to a point right between home plate and the virginity line:] Sharing root PWs [x just before home plate at the end of the orgasm line inside the diamond:] Thigh contact

TED Talk

TED Talk

https://www.xkcd.com/541

https://www.explainxkcd.com/wiki/index.php/541:_TED_Talk

[Randall, drawn as Cueball, on stage.] Randall: Hi. I'm Randall. Welcome to my TED talk. Randall: It's an honor to speak to you, some of the brightest innovators from so many fields, about a problem in desperate need of your attention: Randall: How DO you end parenthetical statements with emoticons? I can't figure out a good way. [Screen next to him shows two statements, both crossed out in red.] "Linux (or BSD :) would..." looks mismatched "Linux (or BSD :)) would..." looks mismatched and weird [Randall writing on a desk.] [Randall's List] Conferences I'm banned from: Siggraph Eurocrypt Defcon Pycon International Astronomical Union Canadian Paleontology Conference Every American Furry Convention American Baking Society Asian Dolphin-Training Conference TED In response to this comic, PyCon organizers jokingly announced that Randall Munroe was banned from PyCon 2009 due to "last year's disgraceful keynote, 'Web Spiders vs. Red Spiders'." They also said they instructed their volunteers to refuse admission to him and "any stick figures who may attempt to register, particularly if they are wearing hats." Messages on the PyCon-Organizers mailing list show that this joke was intended to get Randall to come to PyCon: (The links will only work if you're subscribed to the mailing list.) PyCon mentioned briefly in today's xkcd: http://xkcd.com/541/ We've still never gotten Randall Munroe to actually attend, have we? Anybody want to take charge of twisting his arm this time? I think we can still offer him a "press pass" (free registration). [...] [1] An invite would seem most appropriate given the cartoon. :-) We could also have an official PyCon blog post confirming his ban... [2] How about a public blog post LIFTING the ban and inviting him? [3] Confirming the ban is far funnier... He's definitely a disturbing influence on programmers. [4] Agreed, especially if we invite him concurrently with confirming the ban. [5] (a few posts later) I'm happy to participate in actually throwing some thin guy out of the conference, and then get some graphics savvy person to animate a stick figure over that. :) [...] [6] here's a rough idea of what would show up if you invited him to actually do any speaking... http://www.youtube.com/watch?v=zJOS0sV2a24 it's fairly long. he shows up in the beginning around 3:25. [7] For the record, I did try to convince him to come when got the art for the tshirt last year. He didn't seem super psyched, but then again emotions are hard to read via IRC. I love the idea of "officially" banning him, however. ;-) [8] (a few posts later) OK - posted to the PyCon blog, by the power vested in me as publicity chair. With Michael Foord's excellent sentence added. Now let him know that since he's banned, he HAS to come. [9] Randall has since this comic given a TED talk in March 2014. Randall Munroe Comics that ask "what if?" .

The comics shows Randall as a presenter at the highly prestigious TED conference , a symposium about technology, entertainment and design. The illustrious list of former presenters includes amongst others Bill Clinton, Al Gore, Larry Page, Richard Dawkins and Gordon Brown. The conference is regarded as a forum for digerati . Every talk has a length of at most 20 minutes and is supposed to be as captivating as possible. Randall's presentation, however, reduces the purpose of the conference to absurdity: The topic he wishes to point out to his listeners, is that of how to put an emoticon at the end of a parenthetical statement. This question is of little practical consequence, although it received a lot of attention after publication of the comic. In the last panel, the TED conference is another item to add to his list of conferences from which he has been banned. On the list are other conferences from all sorts of fields, including every American furry convention. The title text about Randall's ban from the IAU conference is a reference to the popular maternal insults called "yo momma" jokes . A common representative of the genre runs "Yo mama so fat, scientists have declared her the 10th planet." Those kind of jokes are a recurring theme on xkcd It can be inferred from 629: Skins , that Randall was banned from North American furry conventions due to being a "Skin", which is a furry whose fursona prefers going around disguised as a human. Depending on Randall's behavior, such an action could generate a lot of drama and, presumably, lead to convention bans. Getting banned from attending a conference is a recurring theme on xkcd, and even in real life, Randall sometimes has bad ideas for conference topics, such as presumably not speaking for the entire conference . This was so far the sixth of eight comics to directly mention conference bans. The first to do so was 153: Cryptography . The PyCon organizers made a response to this comic - see below under PyCon response . Here is a list of the conferences from which Randall has been banned according to this comic. [Randall, drawn as Cueball, on stage.] Randall: Hi. I'm Randall. Welcome to my TED talk. Randall: It's an honor to speak to you, some of the brightest innovators from so many fields, about a problem in desperate need of your attention: Randall: How DO you end parenthetical statements with emoticons? I can't figure out a good way. [Screen next to him shows two statements, both crossed out in red.] "Linux (or BSD :) would..." looks mismatched "Linux (or BSD :)) would..." looks mismatched and weird [Randall writing on a desk.] [Randall's List] Conferences I'm banned from: Siggraph Eurocrypt Defcon Pycon International Astronomical Union Canadian Paleontology Conference Every American Furry Convention American Baking Society Asian Dolphin-Training Conference TED In response to this comic, PyCon organizers jokingly announced that Randall Munroe was banned from PyCon 2009 due to "last year's disgraceful keynote, 'Web Spiders vs. Red Spiders'." They also said they instructed their volunteers to refuse admission to him and "any stick figures who may attempt to register, particularly if they are wearing hats." Messages on the PyCon-Organizers mailing list show that this joke was intended to get Randall to come to PyCon: (The links will only work if you're subscribed to the mailing list.) PyCon mentioned briefly in today's xkcd: http://xkcd.com/541/ We've still never gotten Randall Munroe to actually attend, have we? Anybody want to take charge of twisting his arm this time? I think we can still offer him a "press pass" (free registration). [...] [1] An invite would seem most appropriate given the cartoon. :-) We could also have an official PyCon blog post confirming his ban... [2] How about a public blog post LIFTING the ban and inviting him? [3] Confirming the ban is far funnier... He's definitely a disturbing influence on programmers. [4] Agreed, especially if we invite him concurrently with confirming the ban. [5] (a few posts later) I'm happy to participate in actually throwing some thin guy out of the conference, and then get some graphics savvy person to animate a stick figure over that. :) [...] [6] here's a rough idea of what would show up if you invited him to actually do any speaking... http://www.youtube.com/watch?v=zJOS0sV2a24 it's fairly long. he shows up in the beginning around 3:25. [7] For the record, I did try to convince him to come when got the art for the tshirt last year. He didn't seem super psyched, but then again emotions are hard to read via IRC. I love the idea of "officially" banning him, however. ;-) [8] (a few posts later) OK - posted to the PyCon blog, by the power vested in me as publicity chair. With Michael Foord's excellent sentence added. Now let him know that since he's banned, he HAS to come. [9] Randall has since this comic given a TED talk in March 2014. Randall Munroe Comics that ask "what if?" .

Cover-Up

Cover-Up

https://www.xkcd.com/542

https://www.explainxkcd.com/wiki/index.php/542:_Cover-Up

[Black Hat looking slightly up is holding two rags stained red with blood while Danish is holding an equally bloody mop.] Black Hat: Okay, got the blood off the walls. Danish: I finished the floor. [Black Hat drops the bloody rags behind him while looking up at the ceiling, Danish has put the bloody mop behind her leaning against the wall while covering her mouth with her hands.] Black Hat: Good; he'll be home any- Black Hat: Oh crap! We forgot to clean the ceiling! [Black Hat has moved away from the bloody rags towards Danish who has taken her hands down. They look straight at each other. The bloody mop has fallen over on the floor.] Danish: There's no time! Black Hat: Wait, I'll handle it. [Cueball with briefcase enters the house through the front door behind him, still standing open. He is greeted by Black Hat holding out a hand towards him. The corner of the room and the wall behind them and past the door is outlines with three lines connecting in the corner.] Black Hat: Hi. Did you know "gullible" is written on your ceiling? Cueball: Hah. Yeah, right.

Black Hat and Danish are trying to clean up the mess that some bloody murder most likely performed by them has left. This story may thus be a continuation of 515: No One Must Know . Another guy, Cueball , is on his way home and is about to arrive just when they are finishing the clean up. But then Black Hat realizes that the ceiling has also been stained (by the violent murder...) And now they do not have time to fix it. But Black Hat knows how to deal with the situation, and when Cueball comes home, he says: "Did you know 'gullible' is written on your ceiling?" Gullible means easily deceived or naive. This is a game many people play with each other "Whoa, someone wrote 'gullible' in the sky!" "Did you know when you look at the Microsoft logo upside-down it looks like the word 'gullible'?" Those that are gullible, check. Those that aren't, don't. [ citation needed ] In fact they will pointedly not do the thing that the first person has suggested as a show of how non-gullible they are. Black Hat uses this to his advantage to cover up the copious bloodstains on the ceiling and as expected Cueball just says "Hah. Yeah, right" and refuses to even glance at the ceiling. The title text is hinting that Black Hat has had to cover up killing people several times as this trick has saved him many times. Of course there could also be other things than blood that he had to hide (the money he just stole etc.) [Black Hat looking slightly up is holding two rags stained red with blood while Danish is holding an equally bloody mop.] Black Hat: Okay, got the blood off the walls. Danish: I finished the floor. [Black Hat drops the bloody rags behind him while looking up at the ceiling, Danish has put the bloody mop behind her leaning against the wall while covering her mouth with her hands.] Black Hat: Good; he'll be home any- Black Hat: Oh crap! We forgot to clean the ceiling! [Black Hat has moved away from the bloody rags towards Danish who has taken her hands down. They look straight at each other. The bloody mop has fallen over on the floor.] Danish: There's no time! Black Hat: Wait, I'll handle it. [Cueball with briefcase enters the house through the front door behind him, still standing open. He is greeted by Black Hat holding out a hand towards him. The corner of the room and the wall behind them and past the door is outlines with three lines connecting in the corner.] Black Hat: Hi. Did you know "gullible" is written on your ceiling? Cueball: Hah. Yeah, right.

Sierpinski Valentine

Sierpinski Valentine

https://www.xkcd.com/543

https://www.explainxkcd.com/wiki/index.php/543:_Sierpinski_Valentine

[Shows an adaptation of the Sierpinski triangle fractal, using hearts instead of triangles.] Happy valentine's day. -xkcd

A Valentine's Day card from Randall to the xkcd readers. It is written inside a parody of the Sierpinski Triangle , a Sierpinski Valentine. The Sierpinski Triangle is a fractal pattern made of triangles, covering a space. The way it works is to draw a triangle and draw another (upside down) one in the middle. Choose the upper, left and right triangle and repeat the process. Another valentine in the shape of a heart is 63: Valentine - Heart . The <3 in the title text is an emoticon for a heart and goes out to those of his readers that read the title text . Those who read the title text are usually more devoted to know that such a thing exists. Another relevant comic to the Sierpinski Triangle is 95: The Sierpinski Penis Game . [Shows an adaptation of the Sierpinski triangle fractal, using hearts instead of triangles.] Happy valentine's day. -xkcd

Pep Talk

Pep Talk

https://www.xkcd.com/544

https://www.explainxkcd.com/wiki/index.php/544:_Pep_Talk

[Coach-Cueball stands at the end of a double row of benches in the players locker room. He speaks to his team of five Cueball-like players, two are sitting with towels on the left bench, one stands behind them, and two are sitting on the right bench, one of them resting his head on his hands.] Coach-Cueball: Okay, team. We're sixteen points down. If we want to come back from this— Offscreen: Woo!! Score!!! Coach-Cueball: Okay, now we're eighteen points down. ...Listen—I'm starting to think we should only take these breaks at halftime.

Another comic where Randall takes a less than serious look at sports. The halftime pep talk of a basketball game is commonly used by coaches to inspire their team to either turn the game around, or to defend the lead, and to make strategic changes that will help them do so. Unfortunately, the basketball coach Cueball has absolutely no fundamental understanding of the sport, and has pulled his team (of Cueball-like players) into the locker room while the game is still in progress, not during halftime, enabling the other team to score at will. He could have tried to get a time-out , but still he would not have been allowed to take his team down to the locker room. The title text parodies a common plot of, especially US, sports movies in which an inexperienced team (and sometimes coach) still manage to win a title after a highly motivational pep talk (see for instance Hoosiers ). These Pep talks usually take place during regular pauses of the game, and can lead to a come back from a seemingly insurmountable deficit. In this case the players are not even just poor basketball players but rather chess players and the coach knows nothing of the sport, the opposite of what is usually the case in said movies. And, of course, in this case those pessimistic about their chances were proven right. [Coach-Cueball stands at the end of a double row of benches in the players locker room. He speaks to his team of five Cueball-like players, two are sitting with towels on the left bench, one stands behind them, and two are sitting on the right bench, one of them resting his head on his hands.] Coach-Cueball: Okay, team. We're sixteen points down. If we want to come back from this— Offscreen: Woo!! Score!!! Coach-Cueball: Okay, now we're eighteen points down. ...Listen—I'm starting to think we should only take these breaks at halftime.

Neutrality Schmeutrality

Neutrality Schmeutrality

https://www.xkcd.com/545

https://www.explainxkcd.com/wiki/index.php/545:_Neutrality_Schmeutrality

[Caption above the panel:] Trivia: It's possible to create events which Wikipedia cannot cover neutrally [Black Hat is at a press conference in which he is making an announcement in front of a large crowd mainly of Cueballs but also some Megans.] Black Hat: In a week, I will be donating $1,000,000 to a recipient determined by the word count of the Wikipedia article about this event. If it's even, the money goes to pro-choice activists. If it's odd, pro-life.

Wikipedia is an online encyclopedia with content developed and submitted by volunteers around the world. In fact, its slogan is "Wikipedia, the free encyclopedia that anyone can edit." Most articles on the site can be altered by anyone with access to Wikipedia. Wikipedia has set some standards for its operation, which it refers to as the " Five pillars of Wikipedia ". One of these pillars is titled "Wikipedia is written from a neutral point of view ." Pro-life and pro-choice refer to two opposing viewpoints in the debate of the moral and legal rights concerning abortion . For many on both sides, it is a very emotional topic. Black Hat , like the classhole he is, has decided to prove that you can create an article which fundamentally cannot remain neutral. Since his charitable donation is determined by the word count of the article, any submission to Wikipedia must result in Black Hat's money supporting either pro-life or pro-choice activists. With a reward of one million dollars, it is unlikely that either side would allow an article that would result in the other side winning to remain unedited. The edits need not even overtly change the neutrality of the tone of the article – by simply rewriting 'unbiased' phrases with a differing number of words, the effect of the page is drastically flipped. The title of the comic uses an old (read, "pre-Internet") meme, possibly of Yiddish origin, known as shm-reduplication . The speaker replaces the initial consonant cluster (have it 0, 1 or even 2+ consonants) with the cluster "schm", read /ʃm/, and says the new word after the unadulterated word, as in the title where it is "N" that has been replaced. This denotes an active apathy or an intentional disregard of the authority (for it is usually an authority or someone in a similar position) being mocked. In this case, Black Hat is disregarding Wikipedia's neutrality doctrine with his word count dependent donation rule. The title text is an imagined statement from a Wikipedia contributor attempting to assert the neutrality of their submission, claiming no word count was performed before posting. However, it is nearly impossible to trust that anyone editing such an article would not make an attempt to shift the result in their side's favor, since it is impossible to know whether someone performed a word count. [Caption above the panel:] Trivia: It's possible to create events which Wikipedia cannot cover neutrally [Black Hat is at a press conference in which he is making an announcement in front of a large crowd mainly of Cueballs but also some Megans.] Black Hat: In a week, I will be donating $1,000,000 to a recipient determined by the word count of the Wikipedia article about this event. If it's even, the money goes to pro-choice activists. If it's odd, pro-life.

Music DRM

Music DRM

https://www.xkcd.com/546

https://www.explainxkcd.com/wiki/index.php/546:_Music_DRM

[Cueball sits at his computer.] Cueball [typing]: ...and that's why music DRM is bad for listeners and artists! Megan [off-panel]: What are you doing? [Megan enters and Cueball turns towards her.] Megan: In case you didn't notice, we won the music DRM war. The big stores are DRM free. [Zoom in on Megan who holds up a hand doing the sign of the horns.] Megan: So close the comment thread, get out the debit card, buy us some music, and let's rock the fuck out. [Back to viewing both as in panel 2.] Cueball: But I don't actually like music, I just like being self-righteous on the web. Megan: Lucky for you, that will always be free.

Here, Cueball is commenting in a comment thread that he authored about the negative traits of DRM, or again, Digital Rights Management (also known under 'Digital Restrictions Management'). Cueball has a point: DRM, while meant to fight those who download media through 'dungeon sketchy' maneuvers, risks locking out legitimate owners . In turn, this turns off legitimate buyers from buying the songs, thus hurting artists. Of course, this would be true if the major stores sell music with DRM. Megan , wanting Cueball to make peace and enjoy his goal, makes the following choice quote: 'Close the comment thread, get out the debit card, buy us some music, and let's rock the fuck out', while she shows the sign of the horns . The problem is that Cueball is arguing for the enjoyment of arguing, not out of any actual belief in what he's arguing about. The title text references 132: Music Knowledge while implying that Randall is not really a music fan, since he would only be interested in music that appears in the games that he plays. [Cueball sits at his computer.] Cueball [typing]: ...and that's why music DRM is bad for listeners and artists! Megan [off-panel]: What are you doing? [Megan enters and Cueball turns towards her.] Megan: In case you didn't notice, we won the music DRM war. The big stores are DRM free. [Zoom in on Megan who holds up a hand doing the sign of the horns.] Megan: So close the comment thread, get out the debit card, buy us some music, and let's rock the fuck out. [Back to viewing both as in panel 2.] Cueball: But I don't actually like music, I just like being self-righteous on the web. Megan: Lucky for you, that will always be free.

Simple

Simple

https://www.xkcd.com/547

https://www.explainxkcd.com/wiki/index.php/547:_Simple

[Three Cueball-like guys stand in front of a sketch. The middle Cueball is the protagonist of the comic and will be called Cueball.] Left Cueball-like guy: Do you have any thoughts regarding the particle accelerator's tertiary F.E.L. Guidance System? Cueball: We can't put the broken part in the machine. It wouldn't smash the right tiny things together. Then the machine might break. Cueball: That would be very bad. [Caption below the frame:] I spent all night reading simple.wikipedia.org, and now I can't stop talking like this.

There are three Cueballs discussing a particle accelerator . One Cueball asks the others about the "tertiary Free-electron laser ( F.E.L ) guidance system". As this is a fairly technical topic, we would expect a response filled with scientific jargon. The joke is that the other Cueball instead responds in a much simpler manner. He uses simple phrases such as "smash the right tiny things together" and "that would be very bad". As the caption below the comic notes, Cueball (probably Randall ) has spent the previous night reading the Simple English Wikipedia , a simplified version of Wikipedia intended to be easier to understand, and now he finds himself using similarly simple syntax. For example, the article for a particle accelerator describes it as "a machine that makes really tiny things called particles travel at very high speeds." This is similar to the simple response given by the responding Cueball. In the actual comic, Cueball was able to effectively communicate the dangers of using a broken F.E.L. using simple syntax similar to the style of the Simple English Wikipedia. From the title text, Randall believes that if people teaching advanced mathematics followed this style, their subject would be more accessible. The implication is that more people would be drawn to studying mathematics and that (naturally) the world would be a better place because of this, ironically most likely true! This concept was later revisited in 722: Computer Problems , 1133: Up Goer Five and Thing Explainer (probably most notably), 1322: Winter and 1436: Orb Hammer . [Three Cueball-like guys stand in front of a sketch. The middle Cueball is the protagonist of the comic and will be called Cueball.] Left Cueball-like guy: Do you have any thoughts regarding the particle accelerator's tertiary F.E.L. Guidance System? Cueball: We can't put the broken part in the machine. It wouldn't smash the right tiny things together. Then the machine might break. Cueball: That would be very bad. [Caption below the frame:] I spent all night reading simple.wikipedia.org, and now I can't stop talking like this.

Kindle

Kindle

https://www.xkcd.com/548

https://www.explainxkcd.com/wiki/index.php/548:_Kindle

[Cueball is looking at a tablet.] Megan: A kindle? Ebooks, huh? Cueball: Ebooks are for chumps. Megan: Why get a kindle, then? Cueball: One reason: [Text is above the frame in which Cueball wanders a city with the tablet and with small bubbles forming above his head to indicate him being intoxicated.] Cueball (narrating): Free cellular web access. Even if I spend months broke and drunk in a strange city, I'll still be able to use Wikipedia and Wikitravel to learn about anything I need. [Megan takes the tablet from Cueball.] Megan: Why does that sound familiar? Megan: Gimme that. [Zoom in on the top of the tablet where the name is written:] Amazon Kindle [Zoom out to Megan who scratches at the top of the tablet.] Scrape, scrape, scrape [Zoom back to the damaged top of the tablet where a layer has been scraped off. This partly reveals a new name, where the first and last two letters are only partly visible:] Hitchhiker's Guide

The Amazon Kindle is a device that allows people to read books via ebook format. The comic was published three weeks after Amazon released the Kindle 2 , which included the ability to read Wikipedia articles via the 3G connection that was included with the device. Cueball remarks that "ebooks are for chumps", but goes on to explain the real reason for purchasing a Kindle. Since it has free cellular web access, he could navigate through any city (presumably with 3G access), assisted by Wikipedia and Wikitravel . Megan believes she has heard such a description of a device before and snatches the Kindle away from Cueball. When she scratches off the Amazon Kindle logo at the top of the device she reveals that the device is actually The Hitchhiker's Guide to the Galaxy . This fictional electronic encyclopedia is described in the real-life franchise of the same name. Those works recount the tale of a travel editor who works for and owns a copy of the Guide , which provides travel tips throughout the galaxy, including an entry for Earth . The comic suggests that Amazon simply re-brands copies of the Guide as Kindles. The title text refers to the great utility of having the ability to access Wikipedia for free on an easy-to-carry device. The speaker states that should this utility ever become disabled, he would stage a drunk protest on the lawn of Jeff Bezos , the CEO and founder of Amazon.com. This method of protest is used by the protagonist of the Hitchhiker's series, in the beginning of the first book, in an attempt to prevent his house from being demolished, by lying in front of the bulldozer (in vain). Amazon warned customers using 1st and 2nd generation Kindles in 2021 that 3G connectivity will cease to work, because network operators are upgrading their networks from 3G to 4G. Since this is not Amazon's fault, a drunk protest doesn't seem appropriate though. [Cueball is looking at a tablet.] Megan: A kindle? Ebooks, huh? Cueball: Ebooks are for chumps. Megan: Why get a kindle, then? Cueball: One reason: [Text is above the frame in which Cueball wanders a city with the tablet and with small bubbles forming above his head to indicate him being intoxicated.] Cueball (narrating): Free cellular web access. Even if I spend months broke and drunk in a strange city, I'll still be able to use Wikipedia and Wikitravel to learn about anything I need. [Megan takes the tablet from Cueball.] Megan: Why does that sound familiar? Megan: Gimme that. [Zoom in on the top of the tablet where the name is written:] Amazon Kindle [Zoom out to Megan who scratches at the top of the tablet.] Scrape, scrape, scrape [Zoom back to the damaged top of the tablet where a layer has been scraped off. This partly reveals a new name, where the first and last two letters are only partly visible:] Hitchhiker's Guide

Westley's a Dick

Westley's a Dick

https://www.xkcd.com/549

https://www.explainxkcd.com/wiki/index.php/549:_Westley%27s_a_Dick

[A girl (Buttercup) with long hair and a man (Westley) looking like Cueball but with a bandana lies at the foot of a high cliff. There is a forest in the background] Buttercup: Oh, my sweet Westley! [Buttercup sits on her knees, Westley takes off his bandana.] Buttercup: Why did you let me think you were dead? Westley: You shacked up with the prince! Buttercup: After years of mourning! The worst pain of my life! [Buttercup stands up looking down on Westley who still sits with the bandana in his hand.] Buttercup: And now you ... kill people? Westley: I'd hardly be a dread pirate if I didn't. Buttercup: How lovable. [Westley stands with the bandana in hand while Buttercup walks away from him.] Westley: It was for the sake of the narrative! Buttercup: Fuck the narrative. I'm going to go see if that Spaniard's single. Westley: ...As you wish.

This is an alternate take on the 1973 fantasy romance novel The Princess Bride written by William Goldman which became a film in 1987 . In the movie the main character, Buttercup, believes she has lost her first love to the Dread Pirate Roberts years ago. In the present she is considered one of the most beautiful women of the land and so is being married off to a prince. To provoke a war she has been kidnapped by mercenaries, one of whom is a very honorable Spanish swordsman named Inigo Montoya. A man claiming to be the Dread Pirate Roberts rescues her. On verifying his identity as Roberts, she attacks him by pushing him down a hill. While tumbling down the hill he shouts back "as you wish" identifying him as her first love. She tumbles after, landing on top of him as in the start of this comic. There are, however, several "dick moves" Westley must have made in order for the film's narrative to make sense. Westley breaks the fourth wall and claims he did all of these things for the sake of the narrative . In other words, he did it to make the story better. In the comic Buttercup realizes that Westley has behaved like a dick and chooses to give her love to Inigo Montoya. But in the movie, he and Buttercup end up together in spite of this behavior! The title text shows what looks like a message she and Inigo have written together, for instance in a heart on a tree. Inigo is the Spaniard referred to by Buttercup. Their names, then forever (4eva) and a heart (smiley heart = "<3"), implying they did end up together according to this version of the story. Alternatively, it could simply be the narrator expressing his wish that this will come to pass. It is not the first time Randall has referenced this movie, as the Dread Pirate was referenced in 345: 1337: Part 5 , and a quote from this movie is in the title text of 1427: iOS Keyboard . So it seems like a film that has some meaning for Randall. Note: It's quite possible Westley hasn't been killing people as a pirate at all. People had been surrendering to The Dread Pirate Roberts without a fight for years before he took over the role, due to the terror of his name. Of course, there may be a few people who needed to be killed, over the years, but the implication in the book (and movie) is that at least most surrender without a fight and are presumably unharmed. If you haven't seen the movie or read the book, you may find it helpful to read the synopsis of the book here . [A girl (Buttercup) with long hair and a man (Westley) looking like Cueball but with a bandana lies at the foot of a high cliff. There is a forest in the background] Buttercup: Oh, my sweet Westley! [Buttercup sits on her knees, Westley takes off his bandana.] Buttercup: Why did you let me think you were dead? Westley: You shacked up with the prince! Buttercup: After years of mourning! The worst pain of my life! [Buttercup stands up looking down on Westley who still sits with the bandana in his hand.] Buttercup: And now you ... kill people? Westley: I'd hardly be a dread pirate if I didn't. Buttercup: How lovable. [Westley stands with the bandana in hand while Buttercup walks away from him.] Westley: It was for the sake of the narrative! Buttercup: Fuck the narrative. I'm going to go see if that Spaniard's single. Westley: ...As you wish.

Density

Density

https://www.xkcd.com/550

https://www.explainxkcd.com/wiki/index.php/550:_Density

[Cueball is in a bed with Megan.] Cueball: Sup dawg, I herd you didn't liek forming babby, but I accidentally in your base. [Below the frame:] Cons: Ruined life. Pros: Sentence set the new meme density record.

This comic depicts a sex scene with Cueball in bed together with Megan , and a sentence being spoken by Cueball. The sentence's overt meaning suggests Megan doesn't wish to become pregnant, but Cueball has prematurely or unintentionally ejaculated inside her. The sentence contains five popular (at the time) memes : In plain English, the sentence roughly means: Hey girl, I heard that you don't want to have a baby but I accidentally came inside you. The comic then goes to describe the pros and cons of the situation. "Ruined life" is listed as a major downside, as he may have caused a girl to become pregnant against her wishes, and may have to father a child with her. The usage of memes in response to the situation also conveys an uncaring attitude that is likely to put a damper on their relationship even if she did not get pregnant. On the other hand, it is noted that the sentence could set a new record for the density of memes (most memes packed into the fewest number of words) which can be considered a positive. This explains the title of the comic, though it will be a very superficial and meaningless record, especially when weighed against the downsides. The reason Cueball chose to construct the sentence with so many memes is not clear. Since the comic lists "ruined life" as one of the cons of this scene, it would seem that the accident, as well as the subsequent use of memes, were not planned. It's possible that Cueball had too many memes in his head and couldn't think of anything else to say amid the nervous tension. If this were another character, say Black Hat, then it would be easier to believe that the entire night could have been staged just to give him an opportunity to use the sentence and set a record. The title text references 4chan , a site known for its memes, trolls and other assorted Internet clutter, and sarcastically implies that any advice they might give would in any way be at all helpful. Due to its population of trolls and other unhelpful sorts, advice given by 4chan would normally be useless at best and actively detrimental at worst; however, the title text implies that Cueball regrets that he did not ask 4chan for advice, and maybe have used them for this earlier. [Cueball is in a bed with Megan.] Cueball: Sup dawg, I herd you didn't liek forming babby, but I accidentally in your base. [Below the frame:] Cons: Ruined life. Pros: Sentence set the new meme density record.

Etch-a-Sketch

Etch-a-Sketch

https://www.xkcd.com/551

https://www.explainxkcd.com/wiki/index.php/551:_Etch-a-Sketch

[Cueball is sitting on a bench playing with a pink Etch-a-Sketch.] Cueball: Hey. If I draw enough lines, I can see what's behind the screen. [Close up on the Etch-a-Sketch's screen.] Cueball (off-screen): Oh man, almost... [Cueball looks at the Etch-a-Sketch.] Etch-a-Sketch: Hi! [Head of Megan appears in the black hole Cueball has drawn on the Etch-a-Sketch screen.] Megan: You're cute! [Cueball is looking closer on the Etch-a-Sketch screen.] Cueball: Wha— Megan (out of the Etch-a-Sketch): I'm the one who draws when you turn the knobs. Megan (out of the Etch-a-Sketch): It's lonely in here. [Cueball holds the Etch-a-Sketch further away from his head.] Cueball: It's lonely out here too. Megan (out of the Etch-a-Sketch): I'm glad you found me, then! [Cueball holds the Etch-a-Sketch very close to his face. Panels start to break away into thought bubbles.] Megan (out of the Etch-a-Sketch): Let's be friends Megan (out of the Etch-a-Sketch): And never be alone again. [The next panel is almost gone in the thought bubbles. In the remaining top left corner there are three pink hearts, the top one of these looks like it was drawn on an Etch-a-Sketch.] [From the last two panels the above turns out to have been a fantasy of Cueball. There is a rather large break between the first three lines of panels to the last line. Between the previous line of panels (from the middle panel ) to the last line, there are three large circles, which then continues with seven more inside the next panel down to Cueball sitting with the etch-a-sketch.] Cueball: *Sigh* [Close up of the Etch-a-sketch where the black hole Cueball has drawn shows what is really behind the glass; just the mechanics of the machine, with a pin that moves on a cross and removes the sand from the screen.] [Zoom back out to Cueball who shakes etch-a-sketch above his head.]

Cueball notices that if you draw a lot on an Etch-a-Sketch , the aluminum powder in it can be cleared from enough of the screen to allow a view of the interior (as seen here ). Cueball then proceeds to clear a window into the device, which shows him that there's a girl, Megan , inside whose job is to act as the stylus for the Etch-a-Sketch. She suggest that they be friends, and little hearts pop up. As the dream fades, it then becomes clear that this is just a fantasy, and Cueball sighs at the rather more mundane reality that the lines get drawn by a stylus moving on a simple arrangement of rods. The comic ends with Cueball shaking the Etch-a-Sketch, which resets it and will re-conceal the mechanism. The title text notes that sometimes the mysteries surrounding us turn out to be much more boring than we dream they are. [Cueball is sitting on a bench playing with a pink Etch-a-Sketch.] Cueball: Hey. If I draw enough lines, I can see what's behind the screen. [Close up on the Etch-a-Sketch's screen.] Cueball (off-screen): Oh man, almost... [Cueball looks at the Etch-a-Sketch.] Etch-a-Sketch: Hi! [Head of Megan appears in the black hole Cueball has drawn on the Etch-a-Sketch screen.] Megan: You're cute! [Cueball is looking closer on the Etch-a-Sketch screen.] Cueball: Wha— Megan (out of the Etch-a-Sketch): I'm the one who draws when you turn the knobs. Megan (out of the Etch-a-Sketch): It's lonely in here. [Cueball holds the Etch-a-Sketch further away from his head.] Cueball: It's lonely out here too. Megan (out of the Etch-a-Sketch): I'm glad you found me, then! [Cueball holds the Etch-a-Sketch very close to his face. Panels start to break away into thought bubbles.] Megan (out of the Etch-a-Sketch): Let's be friends Megan (out of the Etch-a-Sketch): And never be alone again. [The next panel is almost gone in the thought bubbles. In the remaining top left corner there are three pink hearts, the top one of these looks like it was drawn on an Etch-a-Sketch.] [From the last two panels the above turns out to have been a fantasy of Cueball. There is a rather large break between the first three lines of panels to the last line. Between the previous line of panels (from the middle panel ) to the last line, there are three large circles, which then continues with seven more inside the next panel down to Cueball sitting with the etch-a-sketch.] Cueball: *Sigh* [Close up of the Etch-a-sketch where the black hole Cueball has drawn shows what is really behind the glass; just the mechanics of the machine, with a pin that moves on a cross and removes the sand from the screen.] [Zoom back out to Cueball who shakes etch-a-sketch above his head.]

Correlation

Correlation

https://www.xkcd.com/552

https://www.explainxkcd.com/wiki/index.php/552:_Correlation

[Cueball is talking to Megan.] Cueball: I used to think correlation implied causation. [Cueball lift his hand while continuing to talk to Megan.] Cueball: Then I took a statistics class. Now I don't. [Back to the same situation as the first frame.] Megan: Sounds like the class helped. Cueball: Well, maybe.

This comic focuses on the apparent difficulty people have in understanding the difference between correlation and causation . When two variables (like blood cholesterol levels and heart disease) are positively correlated, it means that as one variable increases so does the other, whereas a negative correlation means that as one variable increases, the other decreases. The human brain is very good at seeing patterns and deducing rules, and the seemingly natural conclusion is that that the one is leading to the other. In the example, that high blood cholesterol causes heart disease. This may well be true. The positive correlation is certainly not an argument against such a conclusion. But it is only one type of evidence, and is certainly not proof. The relationship between diet and blood chemistry and heart disease is a complex one, but simpler examples abound. For example, if you tallied the sales of sunglasses and incidence of skin cancer by region, you would probably find that there is a high positive correlation. That is, in locations where many people buy sunglasses, there are also many cases of skin cancer. Here it would seem silly to believe that wearing sunglasses can cause skin cancer, but this is exactly the same thinking that allowed us to conclude that blood cholesterol causes heart disease. Correlations do have the ability to mislead us. In this example, both sunglasses and skin cancer are directly affected by a third factor (specifically, a climate where many people expose themselves to the sun). In essence, when two variables are correlated it does not provide evidence that one variable has caused the other. All it says is that their trends move in relation to each other. The correlation could be due to causality, but it could equally be due to other factors, or it could even be a random result. In this situation Cueball is explaining to Megan his realization that correlation is not the same thing as causation. He further explains that his belief changed some time after taking a statistics class. Megan , concludes that the course caused his realization thereby establishing a causation. Cueball's final response of "Well, maybe." is a self-referential joke as there is not enough information to establish causation, only correlation which the class supposedly would have taught him. Being taught something in an academic setting does not necessarily mean a person will readily understand/realize the concept, hence the lack of absolute causation. It could also be a joke on Megan's behalf. Cueball may know whether his new knowledge is caused by the course, but he points out that Megan can't be certain about the causation. The title text plays on two meanings of the word imply : have as consequence, or insinuate. In the statement correlation does not imply causation , correlation is here seen as a person, giving you subtle hints where to look for the cause. This is a metaphor for research, where the correlation must be investigated further, perhaps in a wider scope or with the consideration of more variables, so that the reason for it is understood. For example, Barry Marshall and Robin Warren noticed that the presence of Helicobacter pylori was highly correlated with duodenal ulcer patients. They investigated further. Result: the Nobel Prize in Medicine. In addition, the title text's reference to waggling eyebrows and gesturing furtively while mouthing "look over there" is possibly a reference to the movie Ferris Bueller's Day Off , in which the character of Cameron Frye tries to alert Ferris that Ferris's father is in the next cab over, and they are about to be discovered ditching school. What Randall is saying with this reference is that Correlation (if it were a character in a movie) is desperately trying to draw attention to Causation without openly stating this intention, and perhaps that correlation is a good place to start when looking for causation. At the end, Megan suggests that "the class helped" (which is a causation), but Cueball is not sold, exactly because correlation (taking the class and improved understanding of causation versus correlation) does not imply causation (taking the class leads to improved understanding). [Cueball is talking to Megan.] Cueball: I used to think correlation implied causation. [Cueball lift his hand while continuing to talk to Megan.] Cueball: Then I took a statistics class. Now I don't. [Back to the same situation as the first frame.] Megan: Sounds like the class helped. Cueball: Well, maybe.

Pirate Bay

Pirate Bay

https://www.xkcd.com/553

https://www.explainxkcd.com/wiki/index.php/553:_Pirate_Bay

[Caption above the frame:] Awaiting the judges' ruling at the Pirate Bay trial. [4 Cueball-like guys in a cell: 3 sitting down on a bench and one is standing, presumably looking at the fence.] Cueball: I wish this were in America. Cueball-like guy: Why? Cueball: I hear we'd go before a jury of our peers, and I've always seeded generously.

The Pirate Bay is a website dedicated to facilitating BitTorrent downloads of popular media. The site's servers were taken down, briefly, and the operators were taken to court in Sweden, back in 2009. Unlike normal downloads, files downloaded via Bittorrent are not stored on any web server, but instead transferred in small pieces by other people torrenting the same file; these other people are called "peers." Bittorrent allows websites to provide downloads without using up disk space or bandwidth serving up the entire file; instead, they can host smaller torrent files, which simply describe what the finished file should look like and a few "tracker" servers where lists of other peers can be found, and the peers themselves handle all of the bandwidth issues. This approach is used by a number of websites for completely legal downloads (it's popular among smaller game companies providing digital downloads, for instance), but it's mainly associated with piracy. However, Bittorrent depends on peers actually having the file blocks that you need. People who have already downloaded the entire file, but continue to connect to the network solely to provide that file to others, are called "seeds," and they are an essential part of a healthy torrent. General etiquette demands that people should continue to seed a file until the ratio of data uploaded to data downloaded exceeds 1, although many people feel that one's ratio should be much higher. In any case, closing your torrents as soon as they finish, as mentioned in the title-text, is extremely bad etiquette, so it is punished with nuisance subtitles. This punishment was likely chosen because finding correct and well timed subtitles, in whatever language, for a pirated show tends to be quite hard sometimes. This comic is essentially a pun on this second meaning of the word "peer" - in the US court system, a "jury of your peers" means a jury composed of everyday people like you, while the Pirate Bay operators interpret it to mean a jury composed of people who they've shared files with in the past. The Cueball that does the talking, and thus is the protagonist of the comic, feels that his approach would give him lenience in the trial, since he has always seeded well, thus ensured those peers had a good downloading experience. The title text shows what punishment this kind of peer group would make if they find you guilty - unremovable subtitles in Hungarian . Many pirated videos originate from countries where no dubbed version is available in the regional language, so the only way to understand what's being said is by applying subtitles. These videos are then uploaded with subtitles still included, causing consternation among downloaders who can understand the spoken words but not the subtitles. Annoying Hungarian subtitles are just an example for a language most people don't understand. Finnish, Czech, or Polish wouldn't be better. [Caption above the frame:] Awaiting the judges' ruling at the Pirate Bay trial. [4 Cueball-like guys in a cell: 3 sitting down on a bench and one is standing, presumably looking at the fence.] Cueball: I wish this were in America. Cueball-like guy: Why? Cueball: I hear we'd go before a jury of our peers, and I've always seeded generously.

Not Enough Work

Not Enough Work

https://www.xkcd.com/554

https://www.explainxkcd.com/wiki/index.php/554:_Not_Enough_Work

[Above the first two panels there is a caption:] Signs your coders don't have enough work to do: [Cueball sitting in an office chair at his workstation, with Ponytail standing behind him.] Cueball: I'm almost up to my old typing speed in Dvorak [Cueball is standing next to a server rack pointing at it while looking the other way at a Cueball-like guy. There are three sections filled with servers, two of them together, and space for several more above and below and betwen those two and the one at the bottom. Behind the rack wires comes down tot he floor from all three servers together and the wires then exits the panel to he right along the floor.] Cueball: Our servers now support Gopher. Cueball: Just in case. [In a frame-less panel Megan is standing near her workstation to the right speaking to Cueball to the left.] Megan: Our pages are now HTML, XHTML-Strict, and Haiku-compliant. Cueball: Haiku? Megan: <div class="Main"> <span ID="Marquee"> Blog!</span></div> [Ponytail sitting in an office chair at her workstation.] Ponytail: Hey! Ponytail: Have you guys seen this webcomic?

In some companies, programmers can find themselves under-employed. This may be because these companies have little programming work until something breaks or needs upgrading, or perhaps they are between projects, or simply waiting for a go-ahead. Coders still need to make themselves available to perform emergency fixes, but they may have no other assigned work. This requires them to find constructive ways to spend their time. Or unconstructive, if that is more fun. Dvorak is a keyboard layout that was proposed in 1936 as an alternative to the existing, entrenched QWERTY layout, developed in the 1870s. The QWERTY keyboard is the standard in the US, but some features in its layout are based on mechanical considerations rather than the optimum placement for typing speed. For example, common letter combinations such as 'st' and 'th' had to be arranged so that their operating levers were separated from each other, lest they cause jams and slow down the typist. More than sixty years later, such mechanical considerations could be overcome, and the DVORAK keyboard layout was made with typing efficiency in mind. The Dvorak keyboard was ultimately unsuccessful. It still persists today, but has never threatened the dominance of the QWERTY keyboard. Even if the Dvorak layout is more efficient (which is still a matter of debate, see the uncomfortable truth in 561: Well ), QWERTY was and is the standard. This means that every keyboard user has to learn QWERTY anyway, and there is insufficient benefit in spending the time to learn a new layout, especially when you would have to switch back and forth between Dvorak and QWERTY as the situation demands. Therefore, even seriously considering the switch is a sign that you really have nothing better to do. Another joke is that even though the coder has plenty of spare time on his hands to practice on Dvorak, he has only been able to 'almost' match his old typing speed. This was the first comic to refer to Dvorak, but since then it has become a recurrent theme on xkcd. A later comic, 1445: Efficiency , mentions, in the title text, how you could waste lots of time testing to see if Dvorak is faster. Gopher is a defunct internet protocol, which has been completely superseded by HTTP . It's a perfect example of the kind of thing a programmer might implement in the absence of other, more useful work. (As an aside, the protocol is named for the mascot of the University of Minnesota, where it was developed.) HTML and XHTML are markup languages used to describe web documents. XHTML-strict is a more restricted version of HTML that excludes certain redundant tags like <center>, which is theoretically no longer necessary now that <div> and <span> exist. Haiku , on the other hand, is a kind of Japanese poetry. Rather than having a rhyming meter like Western poetry, Japanese poetry has strict restrictions on syllable count; a haiku must contain three lines, containing 5, 7, and 5 syllables, respectively. The section of code given is HTML markup, and would be read by a web developer like this: Div class equals Main Span ID equals Marquee Blog! end span end div (or alternatively slash span slash div) Which can be divided in syllables like this: Div - class - e - quals - Main Span - I - D - e - quals - Mar - quee Blog! - end - span - end - div This meets the syllable requirements. Restricting yourself to writing markup in this form would be extremely challenging and time-consuming and pointless, so it, too, is a good sign that coders need more real work to do. The title text notes that if you are one of those assholes that are actually pronouncing the angle-brackets, then it would be even harder to write HTML in Haiku format. "Left angle bracket" and "right angle bracket" take up five syllables each on their own. (The asshole part is Randall's opinion about those who do pronounce <>). Haiku was mentioned later in 622: Haiku Proof . Finally, the last panel mentions the biggest timesink of them all: webcomics ! [This is probably self referential.] (Or, even worse, wikis devoted to explaining the jokes in CERTAIN webcomics .) A haiku-compliant programming language does in fact exist: David Morgan-Mar (a creator of many esoteric and parodic languages) invented Haifu , a language that will only compile if it is arranged into subsets of 5 + 7 + 5 syllables. Unlike the HTML example in the comic, Haifu derives its functions and syntax from concepts in Eastern philosophy (such as naming its variable types after the five elements , replacing true and false with yin and yang , and defining arithmetic in terms of creation and destruction). The webcomic referred to in the last panel is most likely Xkcd (setting up a Deadpool-like scenario?) [Above the first two panels there is a caption:] Signs your coders don't have enough work to do: [Cueball sitting in an office chair at his workstation, with Ponytail standing behind him.] Cueball: I'm almost up to my old typing speed in Dvorak [Cueball is standing next to a server rack pointing at it while looking the other way at a Cueball-like guy. There are three sections filled with servers, two of them together, and space for several more above and below and betwen those two and the one at the bottom. Behind the rack wires comes down tot he floor from all three servers together and the wires then exits the panel to he right along the floor.] Cueball: Our servers now support Gopher. Cueball: Just in case. [In a frame-less panel Megan is standing near her workstation to the right speaking to Cueball to the left.] Megan: Our pages are now HTML, XHTML-Strict, and Haiku-compliant. Cueball: Haiku? Megan: <div class="Main"> <span ID="Marquee"> Blog!</span></div> [Ponytail sitting in an office chair at her workstation.] Ponytail: Hey! Ponytail: Have you guys seen this webcomic?

Two Mirrors

Two Mirrors

https://www.xkcd.com/555

https://www.explainxkcd.com/wiki/index.php/555:_Two_Mirrors

[Megan sets up a full mirror facing a bathroom-counter mirror.] [Megan looks through the bathroom counter mirror to see the infinite reflections.] Megan: Bloody Mary, Bloody Mary, Bloody Mary. [Megan ducks as the infinite Bloody Marys pop out between the two mirrors above her head.] RAAGHHHHH In the right-most panel, Megan can still be seen standing in the right mirror even though she had ducked down at that point.

In folklore, Bloody Mary is a legendary ghost or spirit conjured to reveal the future. She is said to appear in a mirror when her name is called multiple times (mainly 3). The Bloody Mary apparition may be benign or malevolent, depending on historic variations of the legend. The Bloody Mary appearances are mostly "witnessed" in teenage group participation games, often as part of a game of truth or dare. This is Bloody Mary's first appearance in xkcd, the second being 2364: Parity Conservation . In this comic, Megan sets up two mirrors facing each other, in which reflections bounce back and forth between the mirrors until the mirrors absorb all the light. She then says "Bloody Mary" three times (as in the folklore) before ducking, conjuring an infinite number of spirits who jump from the mirror towards each other. It's not clear if they simply collide, or pass into the opposing mirror. Megan may be attempting an experiment either in particle physics upon colliding mirror matter or bridging Mirror Universes by enabling Bloody Mary’s opposing characterizations to interact with each other, or both. Douglas Hofstadter (also referenced in 917: Hofstadter ) is the author of Gödel, Escher, Bach and I Am a Strange Loop . In the former book, among many other discussions of infinite loops, he points a television camera at the screen on which its image is projected, forming an endless series of screens similar to panel 2 of this comic. In the latter book he focuses on the idea of minds being self-referential. "In the end, we are self-perceiving, self-inventing, locked-in mirages that are little miracles of self-reference". This blends with the idea of the images of the person looking in the mirror being reflected endlessly. [Megan sets up a full mirror facing a bathroom-counter mirror.] [Megan looks through the bathroom counter mirror to see the infinite reflections.] Megan: Bloody Mary, Bloody Mary, Bloody Mary. [Megan ducks as the infinite Bloody Marys pop out between the two mirrors above her head.] RAAGHHHHH In the right-most panel, Megan can still be seen standing in the right mirror even though she had ducked down at that point.

Alternative Energy Revolution

Alternative Energy Revolution

https://www.xkcd.com/556

https://www.explainxkcd.com/wiki/index.php/556:_Alternative_Energy_Revolution

[A field with seven wind turbines is silhouetted against a dusk sky. One of the turbines is much closer than the others. The panel is double height and width of the two next panels to the right.] [Cueball standing and Megan sitting on the ground are overlooking the wind turbines.] Cueball: I'm all for green energy, but those turbines creep me out. They remind me of War of the Worlds, or the Tripod books. [While the two are in the same position but longer to the left in the panel wiggly lines form around the last word to indicate a high rumbling sound.] Megan: They are unnerving. Cueball: I can't shake the feeling that at any moment they'll— Rumble [The next line in the comic has five small square panels:] [A leg begins to split off one wind turbine.] Crack [The leg separates from the body of the wind turbine.] [The new leg lands on the ground.] Boom [Another leg begins to split off the other side of the wind turbine's body.] Crack [The new leg hits the ground, forming a tripod base.] Boom [A panel even wider than the first, but the same height as the 2nd and 3rd panel. Four of the wind turbines rampage across the field. Six smoke plumes rise from the ground where there are also nine to ten distinct red fires burning. The turbines move towards towers and buildings to the right.] [Cueball and Megan are now both standing. This panel and the last three panels in the last row is all the same size, a third of the total comic in width and the same height as the previous panel.] Megan: Oh no. Cueball: Al Gore, you've doomed us all. Megan: It's coming this way! Cueball: Run! [One of the enormous tripod wind turbine feet lands right behind the running couple, sending debris flying.] Boom [Cueball and Megan run up a small hill (that continue up in the next panel).] Megan: What now? Cueball: Someone has to stop them. Megan: But who could- Voice (off panel): Stand aside! [A man with a black hat and a beard sits mounted on a horse at the top of the hill, lance at the ready.]

Megan and Cueball are looking at modern " windmills " (known as wind turbines ) harnessing wind energy into electrical energy. They comment that there's something creepy about the windmills. They allude to the book The War of the Worlds by H. G. Wells (the Jeff Wayne musical version of The War of the Worlds has paintings of the Martian tripods somewhat like these turbines) and also to John Christopher's Tripods trilogy, a young adult series of books that is also about aliens who ride in walking tripods. Suddenly the windmills' pylons split into three legs, becoming the tripods suggested. They exclaim that Al Gore has doomed us all. Gore is a former Vice President of the United States, known for his environmental activism and promotion of green energy sources, relevant because wind turbines like the ones here are one of the alternative energy sources he supports. In the final frame, the seventeenth-century literary figure Don Quixote arrives. Randall's depiction seems to be inspired by the drawing by Pablo Picasso . In the original story, Don Quixote is a wandering knight of questionable sanity who fights a windmill, which he believes to be a giant. Hence, he is the appropriate person [ citation needed ] to deal with this threat. The title is a joke on the phrase "Alternative Energy Revolution," which normally refers to replacing of harmful power sources with eco-friendly options. However, in this case, the Alternative Energy sources are literally rising up in a revolution against humanity, while their rotor blades are revolving. The title text is another reference to The War of the Worlds : "But there are no bacteria in Mars... when I watched them they were irrevocably doomed... By the toll of a billion deaths man has bought his birthright of the earth, and it is his against all comers." Of course this time we are only saved because we — in spite of having evolved — still produce insane members of our species: some of them occasionally being crazy in a practical way (as Don Quixote's special powers lie in defeating windmills). Wind turbines also appear in later comics. In 1119: Undoing , Randall still seems to dislike them. In 1378: Turbine , the turbine is alive as it is in this comic, though its talking may simply be anthropomorphism. [A field with seven wind turbines is silhouetted against a dusk sky. One of the turbines is much closer than the others. The panel is double height and width of the two next panels to the right.] [Cueball standing and Megan sitting on the ground are overlooking the wind turbines.] Cueball: I'm all for green energy, but those turbines creep me out. They remind me of War of the Worlds, or the Tripod books. [While the two are in the same position but longer to the left in the panel wiggly lines form around the last word to indicate a high rumbling sound.] Megan: They are unnerving. Cueball: I can't shake the feeling that at any moment they'll— Rumble [The next line in the comic has five small square panels:] [A leg begins to split off one wind turbine.] Crack [The leg separates from the body of the wind turbine.] [The new leg lands on the ground.] Boom [Another leg begins to split off the other side of the wind turbine's body.] Crack [The new leg hits the ground, forming a tripod base.] Boom [A panel even wider than the first, but the same height as the 2nd and 3rd panel. Four of the wind turbines rampage across the field. Six smoke plumes rise from the ground where there are also nine to ten distinct red fires burning. The turbines move towards towers and buildings to the right.] [Cueball and Megan are now both standing. This panel and the last three panels in the last row is all the same size, a third of the total comic in width and the same height as the previous panel.] Megan: Oh no. Cueball: Al Gore, you've doomed us all. Megan: It's coming this way! Cueball: Run! [One of the enormous tripod wind turbine feet lands right behind the running couple, sending debris flying.] Boom [Cueball and Megan run up a small hill (that continue up in the next panel).] Megan: What now? Cueball: Someone has to stop them. Megan: But who could- Voice (off panel): Stand aside! [A man with a black hat and a beard sits mounted on a horse at the top of the hill, lance at the ready.]

Students

Students

https://www.xkcd.com/557

https://www.explainxkcd.com/wiki/index.php/557:_Students

[Megan as a teacher speaks to a crowded classroom, where all students are grayed out except one of the Cueball students who is drawn in the normal black line.] Megan: Your projects are due today by 5:00 PM. Cueball (thinking): ...I didn't even know we had one. [Zoom in in Cueball at his small desk still thinking. No other students are visible, but the desk next to his is shown although also fading out.] Cueball (thinking): Wait. I don't think I've been attending. I must have forgotten I had this class. Shitshitshit. [Cueball is sitting at his desk, but now seen from the side, looking from the edge of his desk. The very right part of the drawing, with Cueball's back and chair, now begins to fade.] Cueball (thinking): Okay, I'm gonna fail. Will it hold me back? I just want to get out of here. I thought I had finished my requirements already. [Cueball takes his hand to his face. This panel fades so much it is only about half a panel. Even the frame around the panel disappears.] Cueball (thinking): In fact, I think I remember graduating. What the hell is— [As the previous scene completely fades we find Cueball waking up in his bed with small blobs above his head to indicate the dream disappearing.] [Caption below the last three panels of the comic:] Fun Fact: Decades from now, with school a distant memory, you'll still be having this dream.

This was the first comic with one of Randall's fun facts . Students often dream they have assignments they have forgotten about that are due in a very short time period, leaving no time to complete the assignment, thus filling them with the feeling of impending failure. The panic and helplessness of being unable to complete the work in time only subsides when the dreamer wakes from the nightmare , although sometimes they wake to a reality where there actually is a looming deadline. This comic suggests these dreams continue well after graduation, although there may be a nagging feeling that "I thought I completed everything and graduated". The title text refers to the Green Ranger from the Mighty Morphin Power Rangers , or, indeed, any of the many Power Rangers/Super Sentai seasons with a green ranger. Crisco is a brand of vegetable shortening, a fat that is solid at room temperature and frequently used in baking. The joke is that Randall has a very odd recurring dream, and wants reassurance that he is not the only one... but he likely is! Eleven years later, Megan tells Cueball that just the thought of being in a crowded classroom (even without concerns about an assignment) is scary enough in comic 2285: Recurring Nightmare . But that was due to the COVID-19 pandemic starting in 2020. [Megan as a teacher speaks to a crowded classroom, where all students are grayed out except one of the Cueball students who is drawn in the normal black line.] Megan: Your projects are due today by 5:00 PM. Cueball (thinking): ...I didn't even know we had one. [Zoom in in Cueball at his small desk still thinking. No other students are visible, but the desk next to his is shown although also fading out.] Cueball (thinking): Wait. I don't think I've been attending. I must have forgotten I had this class. Shitshitshit. [Cueball is sitting at his desk, but now seen from the side, looking from the edge of his desk. The very right part of the drawing, with Cueball's back and chair, now begins to fade.] Cueball (thinking): Okay, I'm gonna fail. Will it hold me back? I just want to get out of here. I thought I had finished my requirements already. [Cueball takes his hand to his face. This panel fades so much it is only about half a panel. Even the frame around the panel disappears.] Cueball (thinking): In fact, I think I remember graduating. What the hell is— [As the previous scene completely fades we find Cueball waking up in his bed with small blobs above his head to indicate the dream disappearing.] [Caption below the last three panels of the comic:] Fun Fact: Decades from now, with school a distant memory, you'll still be having this dream.

1000 Times

1000 Times

https://www.xkcd.com/558

https://www.explainxkcd.com/wiki/index.php/558:_1000_Times

[Two almost identical panels are shown with Ponytail sitting behind desk. Above each panel there are a caption and the text in the sign of each panel is slightly different] [Left panel caption above and sign in the panel:] Dishonest Sign: Bailout: $170 billion Bonuses: $165 million [Right panel caption above and sign in the panel:] Honest: Sign: Bailout: $170,000 million Bonuses: $165 million [Caption below the panels:] Dear news organizations: Stop giving large numbers without context or proper comparison. The difference between a million and a billion is the difference between me having a sip of wine and 30 seconds with your daughter, and a bottle of gin and a night with her.

When amounts of U.S. dollars (or other currencies of comparable size) in the millions, billions, or trillions are mentioned in conversation, the impression left by the cited number is not some specific amount, but rather some generically large amount of money. A billion is a thousand times larger than a million, but if one is not paying close attention, they both mentally register as being "very large" or "life-changing if they ended up in my bank account", rather than being as different as "one dollar" and "a thousand dollars" are. In this comic, Randall notes how news organizations take advantage of this fact to make certain figures sound comparable, when the are actually not. The " Bailout " referred to is the 2008 Troubled Asset Relief Program (TARP), wherein money was cheaply loaned to large banks by the government to help them remain solvent. The "Bonuses" are the subsequent bonuses paid by those banks to their employees. Citing the size of the bailout in billions and the size of the bonuses in millions gives the misleading impression that the bulk of the bailout was spent on bonuses - in particular to the very traders who caused the problem that cause the need for TARP in the first place - making for much more outrageous and therefore attention-grabbing story. While the news organizations are not lying per se, citing the figures using the same unit makes it clearer that the bonus payments were a tiny fraction of the bailout which is not as obviously outrageous. The news organizations, as news organizations are, were choosing the presentation that was most attention-grabbing over the presentation that conveys the information most accurately. Below the two comic panels Randall asks the news organizations to stop using this way to misleadingly represent large numbers. He then proceeds to compares the difference between a million and a billion using an analogue that a newscaster may understand. Proportionally speaking, if a million is like Randall taking a sip of wine and spending 30 seconds (presumably talking over the wine) with your daughter, then a billion would be like him drinking a bottle of Gin and spending a night with her (presumably having drunken sex with her). Note that a billion is 1000 millions, and 1000 times 30 seconds does indeed equal 8 hours and 20 minutes, or about "one night". And a bottle of gin (750 mL, 40% ABV) contains 1000 times as much alcohol as a small sip of wine (3 mL, 10% ABV) The title text is a reference to a semi-famous case where Verizon Wireless quoted a rate of 0.002¢ (which equals $0.00002) per kB on their data plan, but charged $0.002. They could not see the difference. [Two almost identical panels are shown with Ponytail sitting behind desk. Above each panel there are a caption and the text in the sign of each panel is slightly different] [Left panel caption above and sign in the panel:] Dishonest Sign: Bailout: $170 billion Bonuses: $165 million [Right panel caption above and sign in the panel:] Honest: Sign: Bailout: $170,000 million Bonuses: $165 million [Caption below the panels:] Dear news organizations: Stop giving large numbers without context or proper comparison. The difference between a million and a billion is the difference between me having a sip of wine and 30 seconds with your daughter, and a bottle of gin and a night with her.

No Pun Intended

No Pun Intended

https://www.xkcd.com/559

https://www.explainxkcd.com/wiki/index.php/559:_No_Pun_Intended

[Caption above the panel:] My Hobby: Appending "no pun intended" to lines with no pun in them. [Cueball is talking to Beret Guy.] Cueball: I think he's internalized his girlfriend's attitudes - no pun intended - and so... [The next panel is inlaid partly over the first panel. Beret Guy is thinking. Above his thought bubble is a caption:] Three hours later: Beret Guy (thinking): "Internalized?" Lied? Analyzed? Or is it "attitudes"? Dammit.

"No pun intended" is an idiom meaning that something just said wasn't meant to be a pun , implying that the preceding statement could be interpreted as one. As done in the comic, following a non-pun with "no pun intended", although factually accurate, breaks this implication and confuses listeners who will be trying to work out which part of the sentence could have been interpreted as a pun. In this comic, which is part of the My Hobby series, Cueball uses this tactic to confuse Beret Guy , who spends the next three hours trying to understand what pun there could have been in Cueball's sentence: I think he's internalized his girlfriend's attitudes . The guy Cueball talks about seems to have taken over ( internalized ) all his girlfriends attitudes, values, standards and opinions, putting these instead of those he has from his own identity or sense of self. This is probably sad, but there is no pun in the sentence. Beret Guy, however, has been fooled by the addition of no pun intended and tries to overanalyze the sentence - did Cueball mean Lied when saying Interna li z ed or was it Analyzed or even Attitudes he meant; could that be the pun? Since there was no pun, he will never find a solution. This was Cueball's plan all along. It seems like Beret Guy, after three hours, finally gives up when he says Dammit . This then leads to the title text joke. Unfortunately for the hobbyist, blank puns default to sexual innuendos, the most notorious example being "If You Know What I Mean." The title text elicits a similar confused reaction, as the most literate people will be more likely to want to spell out " damn it " rather than using the also correct abbreviated form with morphed spelling, dammit , which is referred to as with two m's because many people ( mainly in the US it seems) contract damn it to damnit , which is the "wrong way". [Caption above the panel:] My Hobby: Appending "no pun intended" to lines with no pun in them. [Cueball is talking to Beret Guy.] Cueball: I think he's internalized his girlfriend's attitudes - no pun intended - and so... [The next panel is inlaid partly over the first panel. Beret Guy is thinking. Above his thought bubble is a caption:] Three hours later: Beret Guy (thinking): "Internalized?" Lied? Analyzed? Or is it "attitudes"? Dammit.

Lithium Batteries

Lithium Batteries

https://www.xkcd.com/560

https://www.explainxkcd.com/wiki/index.php/560:_Lithium_Batteries

[Caption above the timeline:] Timeline of commercial uses of lithium batteries: [The panel has a timeline that goes from past to present. The timeline has 4 notches on it. Reading from left to right, with the scale below the line and the description above each notch are the following:] Past [The first notch, closest to the past side, has a picture of an old man with a walking stick.] Pacemakers [The second notch has an image of a man in a car, who is talking on his cell phone.] Phones for Rich Business People [The third notch, has a teen talking on his cellphone.] Phones for Teenagers [The forth notch, closest to the present on the timeline, has an image of a radio controlled toy plane box with a price tag written on it.] Really cheap R/C planes and helicopters Box: $10 Present [Caption below the panel:] Life would be so much better if I were one of those people who aged backward.

Randall muses that his life would have been better if he aged in reverse; this idea is based on a timeline of the usage of lithium-ion batteries . The reasoning is that each of these uses would come to realization when he most needed it; cheap RC planes as a child, a cellphone when he is a teenager and also later for when he is a successful businessman and finally a pacemaker when he is old. The time-reversed aging is probably a direct reference to " The Curious Case of Benjamin Button ", by F. Scott Fitzgerald , a film of which was released in December 2008, a few months before this comic appeared. Randall has used this theme before in 270: Merlin , referencing another backward-time-travelling character (in that case, from " The Once and Future King " by T. H. White ). Lithium-ion batteries have the highest energy density of any widely available battery, and for this reason are commonly used in portable electronic devices such as laptops, tablets and smartphones, and also the newest airliners such as the Boeing 787 Dreamliner . In the title text, Randall states that he is a big fan of cheap radio-controlled aircraft (now powered by cheap lithium-ion batteries), which he most likely wishes would have been available when he was a child. That these have now become so cheap has undoubtedly been the inspiration for this comic. As such, he has an uncontrollable, instinctive urge to make up for his childhood lack of RC aircraft by buying every one he sees compulsively, if they cost less than $30, in spite of him normally being a frugal person. ( Frugality has been defined as the tendency to acquire goods and services in a restrained manner). This tendency has now become a financial problem since cheap RC aircraft have become more and more plentiful, whereas if Randall aged backwards, this wouldn't be an issue - as children rarely make purchases, and adult Randall would live in a world where RCs were still expensive. The one in the comic is priced at only $10. The concept of experiencing events in reverse is also explored in 1869: Positive and Negative Reviews . [Caption above the timeline:] Timeline of commercial uses of lithium batteries: [The panel has a timeline that goes from past to present. The timeline has 4 notches on it. Reading from left to right, with the scale below the line and the description above each notch are the following:] Past [The first notch, closest to the past side, has a picture of an old man with a walking stick.] Pacemakers [The second notch has an image of a man in a car, who is talking on his cell phone.] Phones for Rich Business People [The third notch, has a teen talking on his cellphone.] Phones for Teenagers [The forth notch, closest to the present on the timeline, has an image of a radio controlled toy plane box with a price tag written on it.] Really cheap R/C planes and helicopters Box: $10 Present [Caption below the panel:] Life would be so much better if I were one of those people who aged backward.

Well

Well

https://www.xkcd.com/561

https://www.explainxkcd.com/wiki/index.php/561:_Well

[A sign sits by a well.] The Uncomfortable Truths Well [A Cueball-like guy and Ponytail are lined up for the well; the guy throws a coin in.] Well: For a universe that's supposed to be half Chinese, Firefly sure doesn't have any Asians. [The guy is gone, Cueball and Megsn arrives as a couple lining up behind Ponytail; Ponytail throws a coin in.] Well: There's no solid evidence DVORAK's better than QWERTY. The standard histories are urban legends. [Just the couple remain; Cueball throws another coin in.] Well: You've never said "I love you" and meant it. It was always just words. [Megan has presumably also thrown a coin in the well. This is not shown as for the first three. Cueball waits for her on the other side of the well.] Well: You meant it every time.

This is the first comic in the Well series. It was followed by 568: Well 2 . Uncomfortable truths are truths that exist, but no one wants to have to think about them. The first is about Firefly , the TV series created by Joss Whedon and canceled by FOX , due to poor ratings performance, after airing the first 13 episodes out-of-order . In Firefly , the main languages spoken are English and Chinese (supposedly in equal measure), because China was the only other world power besides America to go to space (Joss Whedon's own explanation on the DVDs). However, there are very few actual Asians on-screen. The second is about two different keyboard layouts, QWERTY and Dvorak. Early typewriters used to jam easily if two nearby keys were struck at about the same time. To work around this, the QWERTY layout, named after the first six letters on its keys, scattered common letter combinations around the keyboard, thus greatly avoiding the problem. (A common myth states that this was done to slow typists down; it was the opposite.) Later typewriter mechanisms were less prone to jamming, which prompted a few people to try to create alternative layouts, such as Blickensderfer's DHIATENSOR layout in 1892, or the Dvorak Simplified Keyboard in 1932. Such layouts never really caught on; by then, typists were all very used to the QWERTY layout, and were unwilling to take the time and effort to learn a new one. In the Dvorak layout, August Dvorak placed the most frequently used keys at the most easily accessible places; Dvorak's advocates claim this reduces typing effort and repetitive strain (as mentioned in the title text) while increasing typing speed and accuracy. However, rigorous, unbiased studies have yet to clearly show significant superiority. (As the title text mentions, the most commonly cited study in Dvorak's favor was overseen by Dvorak himself during his US Navy service in World War II.) This was the second comic to refer to Dvorak after 554: Not Enough Work , and since then it has become a recurrent theme on xkcd. The third and fourth truths are connected: they involve the two people receiving them and (presumably) their relationship with each other. Every time Cueball said "I love you" he never really meant it; whereas Megan meant it every time she said "I love you". This is very uncomfortable for both! This could also be intentional, since in 568, a person called Mike (who happens to be a friend of Megan ), is actually hiding inside the well and tells these uncomfortable "truths", he would have intentionally broken Cueball and Megan up to be able to manipulate Megan in the next installment. The title text perpetuates the Emacs vs. vi debate . Both Emacs and Vim are text editors that are frequently used as general-language editors of source code. The issue is that, while Emacs is more user-friendly and customizable, vim is more lightweight while needing few keystrokes in text editing. Because of this balance, fans of Emacs and fans of vim end up fighting each other. [A sign sits by a well.] The Uncomfortable Truths Well [A Cueball-like guy and Ponytail are lined up for the well; the guy throws a coin in.] Well: For a universe that's supposed to be half Chinese, Firefly sure doesn't have any Asians. [The guy is gone, Cueball and Megsn arrives as a couple lining up behind Ponytail; Ponytail throws a coin in.] Well: There's no solid evidence DVORAK's better than QWERTY. The standard histories are urban legends. [Just the couple remain; Cueball throws another coin in.] Well: You've never said "I love you" and meant it. It was always just words. [Megan has presumably also thrown a coin in the well. This is not shown as for the first three. Cueball waits for her on the other side of the well.] Well: You meant it every time.

Parking

Parking

https://www.xkcd.com/562

https://www.explainxkcd.com/wiki/index.php/562:_Parking

[Black Hat is in a car driving around a parking lot.] [Black Hat's car pulls up next to a red car, that's parked over a line at an angle that block two spaces.] [Black Hat gets out of his car.] SLAM [Black Hat is now holding a blow torch and a rotary saw, He's also wearing goggles and fuel tanks on his back. The blow torch is lit.] Fwoosh [The badly parked car has been cut in half along a diagonal, and the half of the car that was in the second slot has been moved into the same slot as the rest of the car. Black Hat's car occupies the newly freed space.] Black Hat, in the fourth panel, is also seen in the "Your Ad Here" screen.

There are few things so annoying as finding, when a parking lot is full, that someone has parked so carelessly as to take up two spaces. Even worse, it may have been intentional; they decided to exchange the risk of someone accidentally scratching their car for the risk of someone doing it on purpose, see 1030: Keyed . However, there are also non-violent ways to tackle the problem; politely leave a note , or (if possible) just move their car (whether to its proper alignment or to an impound lot). Of course, Black Hat takes the less-traveled path, apparently involving a cutting torch and what looks to be a circular saw . The offending portion of the parked car is sliced off (entirely without surgical precision) and neatly slotted into the remainder of the space. It is now legally parked, but will never become a functional car again. But at least Black Hat finally has space for his own car! This comic may be the one referenced in 496: Secretary: Part 3 , where it is shown that Black Hat '...completely disassembled a car' because 'It was parked across two spaces! It was only fair', or this is the second time that a car has been in the way of him parking, so he has taken matters into his own hands. The title text indicates that a large crowd watched Black Hat at work but refused to identify him, presumably because they feel that the car owner got what he deserved, and possibly because they didn't want to incur Black Hat's wrath. [Black Hat is in a car driving around a parking lot.] [Black Hat's car pulls up next to a red car, that's parked over a line at an angle that block two spaces.] [Black Hat gets out of his car.] SLAM [Black Hat is now holding a blow torch and a rotary saw, He's also wearing goggles and fuel tanks on his back. The blow torch is lit.] Fwoosh [The badly parked car has been cut in half along a diagonal, and the half of the car that was in the second slot has been moved into the same slot as the rest of the car. Black Hat's car occupies the newly freed space.] Black Hat, in the fourth panel, is also seen in the "Your Ad Here" screen.

Fermirotica

Fermirotica

https://www.xkcd.com/563

https://www.explainxkcd.com/wiki/index.php/563:_Fermirotica

[A formula is shown with the variables explained above:] P d Regional population density (e.g. 18,600/mi²) X f Average person's frequency of sex (e.g. 80/year) X d Average duration of sex (e.g. 30 minutes) r=sqrt(2/(π*P d *X f *X d )) On average, someone within distance r of you is having sex. [Cueball standing in front of an easel.] Cueball: Mmm, That probable couple 150 meters away is so hot. Oh yeah, theoretically work it, baby. From out of frame: Hey! No statistical voyeurism!

The Fermi paradox describes the contradiction between the high probability of extraterrestrial life and the lack of empirical evidence thereof. Age and size of the universe suggest that intelligent life should have occurred somewhere, and that some alien civilizations should have developed technology for interstellar travel . Therefore, one might expect the universe full of life. However, no evidence for any lifeforms on other planets has yet been found by humans. This inconsistency was first noted by Enrico Fermi in 1950 when he posed the question "Where is everybody?". The phenomenon, often called The Great Silence , was later examined more thoroughly in a paper by Michael H. Hart . A decade after Fermi's observation, Frank Drake formulated the Drake equation , which aims at estimating the number of active, communicative extraterrestrial civilizations in the Milky Way galaxy. The formula presents itself as the product of several probabilistic factors which would be required for such a civilization to exist. Several parameters are unknown and the equation assumes that all factors are weighed equally, therefore the equation is not useful for computing any actual result. The comic presents a somewhat related equation which computes the average distance from the observer wherein a couple can be found copulating. (The example parameters given in the comic yield 139 metres.) The implication of the equation is that we are surrounded by sex in our everyday lives. Nevertheless, we rarely encounter couples during the act itself. [ citation needed ] Borrowing from the Fermi paradox, the Fermirotica paradox poses the question: "Where is everybody having sex?". Of course, the lack of empirical evidence of couples having sex can easily be explained by the fact that most couples only have intercourse in privacy. A similar approach might also offer an explanation to the original problem: Alien species might conceal themselves from our observations, e.g. in order to avoid interfering in the development of civilizations . This answer to the Fermi Paradox is commonly called zoo hypothesis . The second panel has Cueball sexually aroused by the statistical probability of a couple practising intercourse. This fantasy of his is termed statistical voyeurism by an off-frame speaker, and is evidently upset by it. Possible reasons for being upset are that he considers it an inappropriate use of statistics, or finds voyeurism inappropriate in general, or because it accurately predicts an actual copulation he is aware of and would rather keep private (e.g. the off-frame speaker is actually about to have sex). The title text refers to the Google calculator and praises its capabilities of dimensional analysis , and more specifically unit conversion . Randall assumes that most readers will enter the equation with the example parameters into the Google search engine. The built-in calculator will output the result in the correct SI unit metre , although the population density was given as people per square mile . The second part of the title text states that the examples are nothing more than an educated guess, and that the equation is simplified. In reality, more parameters must be taken into account, e.g. the time of day, since most people will have sex in the evening or night. The insulting suggestion that the probability of sex rises when the reader's (supposedly promiscuous) mother is in town represents a Yo Mama joke . Note that this comic was released on April 1st without being an April Fools' Day comic. But Randall made another April Fool on his reader, see the trivia section . [A formula is shown with the variables explained above:] P d Regional population density (e.g. 18,600/mi²) X f Average person's frequency of sex (e.g. 80/year) X d Average duration of sex (e.g. 30 minutes) r=sqrt(2/(π*P d *X f *X d )) On average, someone within distance r of you is having sex. [Cueball standing in front of an easel.] Cueball: Mmm, That probable couple 150 meters away is so hot. Oh yeah, theoretically work it, baby. From out of frame: Hey! No statistical voyeurism!

Crossbows

Crossbows

https://www.xkcd.com/564

https://www.explainxkcd.com/wiki/index.php/564:_Crossbows

[Cueball is pulling a crossbow out of a desk.] Cueball: Why do you have a crossbow in your desk? Megan (off-screen): You don't ? [Pan to Megan who looks towards Cueball who is off-screen to the left.] Cueball (off-screen): No—why would— Megan: You are studying the consequences of Higgs excitation, aren't you? Megan: Like the rest of the lab? [Cueball, now carying Megan's crossbow joins her as the panel extends to include another Cueball-like guy to her right, he also carries a crossbow.] Cueball: Yes, but why— Guy: Maybe he's slow with the math. Megan: Well, he has until Tuesday. Guy: Poor guy.

There are conflicting theories as to the meaning of this comic. In the first and second interpretations, the title text could refer to literally being the slowest in the lab, and therefore the least able to outrun whatever is making everyone carry crossbows. The proper interpretation of this comic, or whether there even is one, remains an open question. [Cueball is pulling a crossbow out of a desk.] Cueball: Why do you have a crossbow in your desk? Megan (off-screen): You don't ? [Pan to Megan who looks towards Cueball who is off-screen to the left.] Cueball (off-screen): No—why would— Megan: You are studying the consequences of Higgs excitation, aren't you? Megan: Like the rest of the lab? [Cueball, now carying Megan's crossbow joins her as the panel extends to include another Cueball-like guy to her right, he also carries a crossbow.] Cueball: Yes, but why— Guy: Maybe he's slow with the math. Megan: Well, he has until Tuesday. Guy: Poor guy.

Security Question

Security Question

https://www.xkcd.com/565

https://www.explainxkcd.com/wiki/index.php/565:_Security_Question

[Cueball sits at a computer.] Computer Screen: -Email Account Setup- To verify your identity, we need to ask you a question nobody else could answer. Computer Screen: Q: Where are the bodies buried? A: [A text field is shown with "Behind the" typed.] [Cueball sits back and thinks.] [Three stick figures, two wearing police hats and one wearing headphones, watch another computer.] [The same text field is shown with "Behind the ... nice try." typed.] Figure in Headphones: Damn.

Security questions are sensitive questions that allow a user to retrieve or reset his password if the password is lost or stolen. Because of this powerful function, security questions should be treated just as seriously as passwords. Typical security questions include "What's your mother's maiden name?" or "What's your secondary school?" and are intended to be easy for the user to answer but hard for anyone else to answer. In this comic, however, the security question is deployed in a strange way, as the question "Where are the bodies buried?" assumes that one had buried bodies, hence had killed someone. The question turns out to be a ploy by the police, who were trying to bait Cueball into confessing his crime, as well as revealing the location of the incriminating evidence. "I never" is a drinking game that somebody says "I never did something" to the others. If you never did it, you don't need to drink, otherwise, drink. Since he takes a drink for "I never hid any bodies SOUTH of Main Street", the police have narrowed down the search area. The next statement in the game could be "I never hid any bodies WEST of Central Avenue" (or whatever road dividing the area), further localizing the bodies to a quarter of the original search area, in a Twenty Questions manner. Of course, by taking the drink Cueball also admits that he buried bodies, though this evidence would not likely be accepted by any court. [Cueball sits at a computer.] Computer Screen: -Email Account Setup- To verify your identity, we need to ask you a question nobody else could answer. Computer Screen: Q: Where are the bodies buried? A: [A text field is shown with "Behind the" typed.] [Cueball sits back and thinks.] [Three stick figures, two wearing police hats and one wearing headphones, watch another computer.] [The same text field is shown with "Behind the ... nice try." typed.] Figure in Headphones: Damn.

Matrix Revisited

Matrix Revisited

https://www.xkcd.com/566

https://www.explainxkcd.com/wiki/index.php/566:_Matrix_Revisited

[Megan stands below two pieces of text, in a panel that is without a frame.] Today was the ten-year anniversary of the release of The Matrix. I sat down to watch it again. Megan: Holy fuck, ten years ago? [The next three panels of the first row and the next two rows spoofs three scenes from The Matrix.] [In scene 1 Morpheus with sunglasses and Trinity with hair bun are talking to Cueball-Neo. Morpheus has his hands together.] Morpheus: Unfortunately, no one can explain what the matrix is. You have to see it for yourself. [Trinity lifts her hand.] Trinity: Sure you can. It's a computer simulation in which you live, thinking it's reality. Neo: Oh. [Morpheus takes his hands down and turns around glaring at Trinity who has also taken her hand down.] Trinity: ...What? Trinity: Look, maybe you just suck at explaining. [In scene 2 Morpheus is talking to Neo while holding a red pill and a blue pill. To the far right is a part of a table.] Morpheus: ...Or you take the red pill, and I show you how deep the rabbit hole goes. [Neo takes both pills from Morpheus.] [Neo crushes both the red and blue pills on a table top.] Crush [Neo snorts the resulting purple powder through a pipe he holds up to his face (his nose).] Snort [Morpheus and Neo are shown upside down in a frame with inverted colors, i.e., black background with white lines.] Morpheus: Now look what you've done. Neo: Where are we? Morpheus: I have no idea. [In scene 3 Neo, wearing a long, black trench coat, at a metal detector, is accosted by the Cueball-like security guard.] Guard: Please remove any keys, metallic items, weapons— [Neo steps close to the guard and opens his trench coat towards the guard, who is facing the reader. The reader can't see what Neo has under his coat.] [Same scene as above, but side view: Neo, on the left, is opening his coat toward the guard, who is on the right and seems to be looking down. Nobody speaks.] [Same scene as above but the guard now looks up to Neos face and finally speaks:] Guard: Eww. [In the last row of the comic we see three characters that have obviously just finished watching The Matrix. Cueball is sitting on the floor nearest to the TV, Megan is sitting on the floor, farther from the TV and a Cueball-like friend is sitting on an armchair, farthest from the TV.] Cueball: I forgot how good that movie was. Friend: Wanna put on the other two? [Cueball, still sitting has turned to face Megan. They exchange looks without speaking.] [View of room, which is now empty, as is the chair. Sounds comes from off-screen to the right.] Crash Wham Friend (off-screen): Ow! Ow! [Cueball and Megan are back in the room, zoomed in so the TV is no longer visible, but the chair is and it remains empty. The friend is nowhere to be seen.] Cueball: I forgot how good that movie was. Megan: Too bad they never made any sequels. Cueball: True.

In the first frame it is stated that the comic was released on the anniversary of the movie The Matrix . This is not true. The Matrix was released 31 March 1999 in the US, although it was next released in Australia on 8 April 1999, ten years before the release of this comic. But maybe Randall drew the comic (and had watched the movie) on the true 10 year anniversary day. Megan is shocked when she realizes it is already ten years ago that The Matrix came out. This is an effect Randall has used to make you feel old several times (for instance he mentions The Matrix again two years later in 891: Movie Ages .) In The Matrix , almost all of humanity lives in a computer simulation. Many years ago, robots took over the real world (not the simulation), and placed humans into the simulation while their body heat generated power for the robots. A few people have escaped from the Matrix, and they are on a mission with others to free the human race from the robots. The title of the strip is a reference to the documentary on the filming of The Matrix : The Matrix Revisited . In the first three rows of the comic we see three famous scenes from The Matrix parodied by Randall. The characters are Morpheus , with sunglasses; Neo , as Cueball in the first two scenes and with a black coat in the third scene; Trinity , as Hairbun ; and a security guard in the third scene, as another Cueball-like guy. In the first scene Morpheus tells Neo that one cannot explain what the Matrix is and that he must see it for himself to understand. Morpheus is very mysterious as he tempts Neo to take a look himself, which, in the movie, leads to the next scene. In this comic, however, Trinity makes Morpheus look foolish by clearly explaining the Matrix in a single, simple phrase, and then telling him that he must suck at explaining. (The actual quote from the movie is no one can be told what the Matrix is , which makes more sense: even after being rescued from the Matrix, Neo at first refuses to accept that his entire life has been a simulation, becoming highly distraught when confronted with that truth. Morpheus later mentions that for this reason, it is unusual to rescue people past a certain age.) In the next scene Morpheus tries to ignore Trinity's remark and continues by showing Neo two pills, one red and one blue, and tells Neo that he can either take the blue pill and return to the simulation (the Matrix), never to hear about the Matrix again, or he can take the red pill and leave the Matrix, and "see how deep the rabbit hole goes" (a reference to Alice in Wonderland ). In the movie, Neo takes the red pill. In the comic, however, he mixes the two pills then snorts the purple powder he has created as though it was an illegal drug such as cocaine, and apparently winds up in a bizarre upside down and inverted dimension, presumably caused by his 'Drug Trip'. Even Morpheus now has no idea where they are. Note that the inversion of both color and orientation could be intended to evoke the idea of capturing an image on film (i.e. a film negative), which is really the only place where Neo and Morpheus exist. It is possible that the combination of pills allowed Neo to break through another layer of the simulation. Alternatively, this could simply be Randall trying to explain that they are in an alternate dimension whilst still remaining within the constraints of stick figures on white and black backgrounds. What leads up to the third scene is when Neo and Trinity must save Morpheus, who has been captured by agents of the simulation. They obtain many guns and load them into trenchcoats. In the shown scene Neo is stopped at a security checkpoint in a building in the Matrix. A security guard tells him to remove any metallic items, since the scanner has shown him to have metal on his person, such as keys, and place them in a bin, then walk through the scanner again. In the movie, he opens his trenchcoat, revealing a myriad of weapons and dispatching all of the guards with the assistance of Trinity. In the comic, however, Neo opens his trenchcoat, but the guard's response of "eww" implies that Neo is otherwise naked and the guard is disgusted by his display of his genitals. It is possible that Neo, on account of having many metal implants (seen in the movie as being in the bodies of everyone raised by the robots), is trying to remove his implants, thus starting to take his clothes off. After watching the movie, Cueball turns to his friends (Megan and another Cueball-like guy) and exclaims that he had forgotten how great the movie is. When his friend suggests that they put on the other two sequels, there is a beat panel where Megan and Cueball look at each other, then they beat up the offender off-panel. The two sequels to The Matrix are widely regarded as inferior to the original, with some fans pretending they don't exist . This is what happens when Megan and Cueball return, and Cueball repeats his statement about how good it was. Then Megan is saddened by the fact they never made any sequels and Cueball agrees. Thus trying hard (even violently) to forget those sequels. On IMDb the original movie was still in the top 20 on their top 250 chart in July 2015, with an average of 8.7 vs. only 7.2 and 6.7 to the sequels (though even those two scores are relatively high compared to other action titles). 9 years (and one day) later Randall made the comic 1978: Congressional Testimony where the movie The Terminator is mentioned. In the title text a similar line of thought as the one in the bottom strip of this comic is made. The third movie in the Terminator Franchise was so great that Skynet sent back a robot to prevent James Cameron, the director of the first two Terminator movies, from directing it, and instead another (much worse) version of the movie was later directed by another director. This indicates that Randall would rather not have had the third movie made, and also fantasizes about how much better it could have been with the original director making T3. [Megan stands below two pieces of text, in a panel that is without a frame.] Today was the ten-year anniversary of the release of The Matrix. I sat down to watch it again. Megan: Holy fuck, ten years ago? [The next three panels of the first row and the next two rows spoofs three scenes from The Matrix.] [In scene 1 Morpheus with sunglasses and Trinity with hair bun are talking to Cueball-Neo. Morpheus has his hands together.] Morpheus: Unfortunately, no one can explain what the matrix is. You have to see it for yourself. [Trinity lifts her hand.] Trinity: Sure you can. It's a computer simulation in which you live, thinking it's reality. Neo: Oh. [Morpheus takes his hands down and turns around glaring at Trinity who has also taken her hand down.] Trinity: ...What? Trinity: Look, maybe you just suck at explaining. [In scene 2 Morpheus is talking to Neo while holding a red pill and a blue pill. To the far right is a part of a table.] Morpheus: ...Or you take the red pill, and I show you how deep the rabbit hole goes. [Neo takes both pills from Morpheus.] [Neo crushes both the red and blue pills on a table top.] Crush [Neo snorts the resulting purple powder through a pipe he holds up to his face (his nose).] Snort [Morpheus and Neo are shown upside down in a frame with inverted colors, i.e., black background with white lines.] Morpheus: Now look what you've done. Neo: Where are we? Morpheus: I have no idea. [In scene 3 Neo, wearing a long, black trench coat, at a metal detector, is accosted by the Cueball-like security guard.] Guard: Please remove any keys, metallic items, weapons— [Neo steps close to the guard and opens his trench coat towards the guard, who is facing the reader. The reader can't see what Neo has under his coat.] [Same scene as above, but side view: Neo, on the left, is opening his coat toward the guard, who is on the right and seems to be looking down. Nobody speaks.] [Same scene as above but the guard now looks up to Neos face and finally speaks:] Guard: Eww. [In the last row of the comic we see three characters that have obviously just finished watching The Matrix. Cueball is sitting on the floor nearest to the TV, Megan is sitting on the floor, farther from the TV and a Cueball-like friend is sitting on an armchair, farthest from the TV.] Cueball: I forgot how good that movie was. Friend: Wanna put on the other two? [Cueball, still sitting has turned to face Megan. They exchange looks without speaking.] [View of room, which is now empty, as is the chair. Sounds comes from off-screen to the right.] Crash Wham Friend (off-screen): Ow! Ow! [Cueball and Megan are back in the room, zoomed in so the TV is no longer visible, but the chair is and it remains empty. The friend is nowhere to be seen.] Cueball: I forgot how good that movie was. Megan: Too bad they never made any sequels. Cueball: True.

Urgent Mission

Urgent Mission

https://www.xkcd.com/567

https://www.explainxkcd.com/wiki/index.php/567:_Urgent_Mission

[Cueball is coming out of star shaped hole, the hole has black stripes in it. Cueball has one leg inside but the rest of his body outside the hole. He points one arm at Benjamin Franklin. Franklin is sitting in a chair at his desk writing with a quill on a piece of paper. He is drawn with square glasses and long hair, but only at the back of his head, leaving most of his head bald.] Cueball: Benjamin Franklin? Franklin: Yes? Cueball: I bring a message from the future! I don't have much time. Franklin: What is it? Cueball: The convention you're setting for electric charge is backward. The one left on glass by silk should be the negative charge. [Caption below the panel:] We were going to use the time machine to prevent the robot apocalypse, but the guy who built it was an electrical engineer.

Benjamin Franklin was one of the Founding Fathers of the United States . Aside from uniting most of his country against Great Britain 's rule, he was also a model of a renaissance man : an author, painter, musician, politician, postmaster, inventor, scientist, and diplomat. Some of his legacies include bifocals, the Franklin stove, an odometer for a horse-drawn carriage, the almanac, and abolitionist ideals. He has since been honored with the use of his image on the $100 bill. Franklin also did several experiments regarding electricity , and invented the lightning rod . He discovered the fundamentals of electricity, including positive and negative charges, as well as the principle of conservation of charge. When Franklin first wrote down his notes for electricity, he defined a positive charge as one left on a glass rod by rubbing it with silk, and a negative charge as one left on rubber by rubbing it with fur. Without realizing it, this meant that he had assigned a negative value to the charge on the electron, later identified as the fundamental carrier of electrical charge. In an electrical circuit, we envisage the charge to be flowing from positive to negative. This is analogous to energy flowing from a region of high temperature to one of low temperature, or a fluid moving from an area of high pressure to one of low pressure. However, because an electron is negatively charged, the actual flow of electrons is in the opposite direction, from negative to positive. This reversal of the natural expectation has caused unnecessary confusion to many fledgling engineers. In the comic, the invention of a time machine was commissioned with the intent of preventing a robot apocalypse like in Terminator movies, a recurring theme on xkcd. However, the Cueball that built and used the machine is an electrical engineer with misplaced priorities, believing that reversing Franklin's "mistake" takes precedence over eliminating a more immediate threat to the human race. Cueball tells Franklin that the charge left on a glass rod by rubbing it with silk should be the negative charge, not the positive charge, because the friction removes electrons from the rod. This would not have been intuitive to Franklin, because the electron had not as of yet been discovered. Yet by telling Franklin to reverse the positive and negative conventions, this would ultimately result in an alternate universe where electrons are assigned a positive charge. One can only speculate what other changes this reversal of convention would lead to, as small changes tend to cascade into huge ones . Would the positron have been instead named the negatron? And would this affect the success of the Transformers franchise? In the title text, Cueball defends his actions, stating that preventing the rise of dictators or pandemics is a fine idea, but here they have a chance of making the signs on "every damn diagram" make sense, which to him seems so much more important. Cueball is likely voicing Randall 's frustration with this breach of logic, albeit exaggerated to comedic levels. [Cueball is coming out of star shaped hole, the hole has black stripes in it. Cueball has one leg inside but the rest of his body outside the hole. He points one arm at Benjamin Franklin. Franklin is sitting in a chair at his desk writing with a quill on a piece of paper. He is drawn with square glasses and long hair, but only at the back of his head, leaving most of his head bald.] Cueball: Benjamin Franklin? Franklin: Yes? Cueball: I bring a message from the future! I don't have much time. Franklin: What is it? Cueball: The convention you're setting for electric charge is backward. The one left on glass by silk should be the negative charge. [Caption below the panel:] We were going to use the time machine to prevent the robot apocalypse, but the guy who built it was an electrical engineer.

Well 2

Well 2

https://www.xkcd.com/568

https://www.explainxkcd.com/wiki/index.php/568:_Well_2

[Four people are lined up by a covered well, Ponytail in front followed by Cueball, Megan and a man with some kind of hat (could be Beret Guy, but only half of his head is shown so it is not clear). A large sign stands well in front of the well. Ponytail throws in a coin.] Well: Science may discover immortality, but it won't happen in the next eighty years. Sign: The Uncomfortable Truths Well. [Zoom in on the well and Cueball who throws in a coin.] Well: You'll never find a programming language that frees you from the burden of clarifying your ideas. Cueball: But I know what I mean! [Same zoom in on Megan who throws in a coin.] Well: You avoid your friend Mike because you're uncomfortably attracted to him. [Megan bend in over the well looking down] Megan: Nice try, Mike. Megan: Get out of the well. Mike (from inside the well): Aww.

This is the second comic in the Well series: The first was 561: Well . The average person's lifespan is 80 years now. So, while immortality may become a reality within the coming century, Ponytail won't live long enough to achieve it. Cueball is looking for a programming language that does not need him to be specific about his ideas. When humans communicate ideas to other humans they may be vague but still understood, since the listener can infer a lot of detail from context and basic knowledge. Until we start 'raising' compilers (like you would a child) compilers will not possess that feature. Hence the need for the programmer to be exact in communicating his ideas to the compiler. No language will ever be able to change that. Cueball complains that he knows what he means, perhaps hoping that this is perfectly sufficient . Finally we find out that one of Megan 's admirers, Mike, whom she avoids, is hiding in the well. He has been waiting for her to come for her uncomfortable truth , so he can make her believe that she is actually attracted to him. But she is not so easily fooled and calls his bluff, telling him to come out of the well. The title text suggests he might also have been down there for the money everyone is throwing in to the well to get this uncomfortable truth. So it has never been a working well. When everyone (or just Megan) finds out about this, Mike is bombarded with the all the pennies people have brought along. In the comic game 1608: Hoverboard there is also a well in the left part of the world. This well has the same type of covered top and at the bottom (it is very deep) there is a girl and above her a coin, like the one thrown into a wishing well. On these links, to images on xkcd ; used in the game, the top and the bottom of the well can be seen. [Four people are lined up by a covered well, Ponytail in front followed by Cueball, Megan and a man with some kind of hat (could be Beret Guy, but only half of his head is shown so it is not clear). A large sign stands well in front of the well. Ponytail throws in a coin.] Well: Science may discover immortality, but it won't happen in the next eighty years. Sign: The Uncomfortable Truths Well. [Zoom in on the well and Cueball who throws in a coin.] Well: You'll never find a programming language that frees you from the burden of clarifying your ideas. Cueball: But I know what I mean! [Same zoom in on Megan who throws in a coin.] Well: You avoid your friend Mike because you're uncomfortably attracted to him. [Megan bend in over the well looking down] Megan: Nice try, Mike. Megan: Get out of the well. Mike (from inside the well): Aww.

Borders

Borders

https://www.xkcd.com/569

https://www.explainxkcd.com/wiki/index.php/569:_Borders

[Two Cueball-like guys stand on a hill overlooking a great city. One of them points at the city. Between them and the city stands an embassy flying a red flag. The text is not spoken by either of the guys.] Three years ago, the kingdom of Liate overthrew their old order and established a constitutional monarchy. Our leaders signed a treaty with their queen, and our borders were set by the Yarbis Accords. Many said war would be unending, that peace would always be a dream deferred. But today, our flag flies proudly over our embassy in their kingdom, and they walk our lands without fear. So come, traveller. Lay down your grudges and join us in brotherhood. It is time not to fight, but to live. [Cueball sitting at computer.] Cueball: This is the worst capture-the-flag server ever.

Capture the flag (CTF) is a common way of playing games where the objective is to capture the opponent's flag while protecting your own team's flag. This comic describes a CTF server that Cueball joins for an online war game where peace has been established and no one is trying to capture the opponent's flags, therefore making the game unexciting and pointless, as Cueball says in the last panel. The title text refers to the line of flags in front of UN buildings. If such a collection of flags of all the teams were established on a server, one could get a very high score by quickly capturing all of them. A kajillion is slang for "an unspecified large number." [Two Cueball-like guys stand on a hill overlooking a great city. One of them points at the city. Between them and the city stands an embassy flying a red flag. The text is not spoken by either of the guys.] Three years ago, the kingdom of Liate overthrew their old order and established a constitutional monarchy. Our leaders signed a treaty with their queen, and our borders were set by the Yarbis Accords. Many said war would be unending, that peace would always be a dream deferred. But today, our flag flies proudly over our embassy in their kingdom, and they walk our lands without fear. So come, traveller. Lay down your grudges and join us in brotherhood. It is time not to fight, but to live. [Cueball sitting at computer.] Cueball: This is the worst capture-the-flag server ever.

New Car

New Car

https://www.xkcd.com/570

https://www.explainxkcd.com/wiki/index.php/570:_New_Car

[A Cueball-like guy is standing behind, a sports car where Cueball sits turned toward him.] Friend: When'd you get the car? [Zoom-in on Cueball in the car.] Cueball: It's the darndest thing. We bought it as a prize for the 100,000,000 th visitor to our website. [Zoom-in on the friend.] Friend: And they didn't want it? Cueball (off-screen): Apparently. [Pan to where both the friend and Cueball in the car can be seen, but not the front of the car.] Friend: Maybe they didn't see the notice. Cueball: It was flashing and everything! Friend: How bizarre.

Cueball is sitting in a nice sports car, and his (Cueball-like) friend asks when he got it. It turns out it was bought as a prize supposed to be delivered to the 100,000,000th visitor to his company's website. But the user did not react to the notice on the page about the prize, even though it was flashing . A well-known type of Internet scam tries to trick the reader into thinking that they've won a prize, often in the form of an annoying flashy ad banner (e.g. " You're our 100,000,000th visitor!!! Click HERE to claim a FREE Ferrari! "). A typical clickbait . Cueball actually really did have a fancy car to give out, but the winner didn't claim it, believing it to be a scam. It is a bit like the boy who cried wolf — given enough lies, the truth will eventually look like a lie. (As coincidences would have it, exactly the same joke appears in the much-loved British comedy series That Mitchell and Webb Look , in a 2006 John Finnemore sketch about a "MASSIVE YACHT!" giveway. Presumably Randall hadn't come across the Mitchell and Webb version when he wrote this comic three years later.) The title text refers to another type of scam: advertising fake " male enhancement " drugs. Randall suggests that if such a drug really did exist, it would be very difficult to advertise effectively, since most people would assume it was a scam. Additionally there may be a relation implied (intersection) between people having sports cars and people needing penis enlargements: big cars to compensate feelings of inferiority [ citation needed ] (or red cars to compensate for cyanness ). [A Cueball-like guy is standing behind, a sports car where Cueball sits turned toward him.] Friend: When'd you get the car? [Zoom-in on Cueball in the car.] Cueball: It's the darndest thing. We bought it as a prize for the 100,000,000 th visitor to our website. [Zoom-in on the friend.] Friend: And they didn't want it? Cueball (off-screen): Apparently. [Pan to where both the friend and Cueball in the car can be seen, but not the front of the car.] Friend: Maybe they didn't see the notice. Cueball: It was flashing and everything! Friend: How bizarre.

Can't Sleep

Can't Sleep

https://www.xkcd.com/571

https://www.explainxkcd.com/wiki/index.php/571:_Can%27t_Sleep

[Cueball is in bed, presumably trying to sleep. The top of each panel is a thought bubble showing sheep leaping over a fence and Cueball's counting and the sheeps baaing is written above the sheeps. Two sheep are jumping from left to right in the first panel.] 1... 2... Sheep: Baaa [Two sheep are jumping from left to right. Cueball is holding his pillow.] ... 1,306... 1,307... Sheep: Baaa [A whole flock of sheep (nine visible) is jumping over the fence from right to left; the first and last sheep is cut off at the edge of the frame. Cueball is now sitting up looking up at his thought bubble.] ... 32,767 ...-32,768... Sheep: Baaa baaa baaaa baaa ba Cueball: ? [Two sheep are again jumping from left to right. Cueball is holding his pillow over his head.] ...-32,767... -32,766... Sheep: Baaa

Cueball is in bed and is having trouble sleeping. He tries the old standby of counting sheep as they jump over a fence, but upon reaching 32,767 sheep, 65535 sheep jump back over the fence and start counting up again from -32,768. This is a reference to an integer overflow, when an increasing amount (sheep in this case) suddenly overflows and shows up as a negative value. This is because when a whole number or integer is represented in a digital form, such as on a computer, the number's range is limited by the amount of space used to store it. When the greatest possible number given the storage space is exceeded, an arithmetic overflow occurs, which may result (depending on the used language among other things) in starting over at the least possible number given the storage space, similar to a car's odometer. Imagine an odometer with six digits reaching 999999. Upon driving one more mile or km, the digits will roll back over to 000000. Causing or failing to prevent integer overflow is a common mistake by programmers that may have software security consequences. Some languages like C/C++ even leaves the signed integer overflow undefined behavior , it may or may not wrap to the beginning, the instruction can be ignored or may cause the software to crash. In this case, the least and greatest possible numbers are -32,768 and 32,767, which implies that the storage space used would be 16 bits. In addition, it's clear that the number is designated as a signed number, meaning that it can be either positive or negative. However, even if Cueball had this limitation, it would never actually pose a problem. By 32,767 sheep, at a rate of one sheep per second, Cueball has been counting for 9.101 hours (or about 9 hours 6 minutes). This would signify that he has extreme insomnia and probably needs treatment, and also that he has spent the entire night counting, and therefore would just get up and start the day rather than count sheep all over again from -32,768. The title text refers to the 1968 Philip K. Dick science fiction novel Do Androids Dream of Electric Sheep? , which was adapted into the perhaps more widely known Ridley Scott directed 1982 film Blade Runner . The implication is that if we ever do create androids that dream of electric sheep, we should make sure to give them sufficient storage space to store numbers large enough such that an arithmetic overflow will be far less likely to occur, even if they count for a long time. A "long int" typically consists of four bytes rather than two, so instead of being limited to a range from -32,768 to 32,767 the number will be capable of storing numbers from -2,147,483,648 to 2,147,483,647, which would take 68.1 years to exhaust. "sheepCount" is a possible name for a variable to be used in a computer program. Declaring a variable tells the computer that it should allocate a portion of memory to be associated with the variable name given. For those who might be unfamiliar with common programming practices, "sheepCount" is named using what is commonly referred to as CamelCase , meaning that all words in the name ("sheep" and "count") are pushed together and the first letter of every word after the first is capitalized. This is one of several common approaches to naming variables in computer programming. This is because you can only have capital and lowercase letters, numbers, and underscores in variable names in most languages, and the names cannot start with a number. An alternative is snake_case , where the spaces are replaced with underscores and the names are lowercase. [Cueball is in bed, presumably trying to sleep. The top of each panel is a thought bubble showing sheep leaping over a fence and Cueball's counting and the sheeps baaing is written above the sheeps. Two sheep are jumping from left to right in the first panel.] 1... 2... Sheep: Baaa [Two sheep are jumping from left to right. Cueball is holding his pillow.] ... 1,306... 1,307... Sheep: Baaa [A whole flock of sheep (nine visible) is jumping over the fence from right to left; the first and last sheep is cut off at the edge of the frame. Cueball is now sitting up looking up at his thought bubble.] ... 32,767 ...-32,768... Sheep: Baaa baaa baaaa baaa ba Cueball: ? [Two sheep are again jumping from left to right. Cueball is holding his pillow over his head.] ...-32,767... -32,766... Sheep: Baaa

Together

Together

https://www.xkcd.com/572

https://www.explainxkcd.com/wiki/index.php/572:_Together

[Cueball and Megan are running in a field, holding hands. They are running away from another pair which also looks like Cueball and Megan. This pair stands in the background, next to a small box. There may be something lying on top of the box, but it is difficult to see clearly. The sun is shining above them.] [Cueball and Megan are in a boat on a lake, very romantic. Cueball is speaking to Megan, illustrated with a heart.] Cueball: ♡ [Cueball and Megan sit together on a bench on a beach, watching the sunset.] [Cueball and Megan stand in front of an altar under a wedding arch, with confetti falling around them. He is wearing a butterfly and she a veil.] [Cueball and Megan, now old and wrinkled, sit together holding hands on their porch at the top of a small stair outside their house. He has a sailor cap on and Megan now wears her hair in a bun. Although the woman looks like Hairbun, and the old man is wearing a sailor cap, we can assume this is still Megan and Cueball given the juxtaposition of the preceding panel.] [The same setting is depicted but seen from the side of the house. Cueball begins walking away from Megan using his cane. He has descended from the stair. Finally, Megan speaks, and unusually there is a speech bubble, with an extra smaller bubble hanging on to it for the second sentence.] Megan: Dear? Where are you- Megan: Come back! [Cueball approaches an old couple, presumably the kids from the first panel now turned old. They seem tired, looking down all the time. The man only has hair around his neck and also a cane. The woman has long thinning hair. The box from the first panel is between Cueball and the other two. On top of it lies a piece of paper] [Same picture except that Cueball is now standing still and has picked up the paper from the box and writes on it with a pen. Again there is a speech bubble.] Cueball: Okay, [The paper is shown. It is a scavenger hunt list with at least six items. The three first items have been checked off. The last item is blocked by the speech bubble, but can be seen to be there from the check box.] Scavenger hunt: ☒ Indian-head penny ☒ Snake skin ☒ Happiness ☐ Four-leaf clover ☐ Shark tooth ☐ [covered by speech bubble] Cueball (off-panel): What's next?

Cueball and Megan are seen running together hand in hand. Behind them, two others (who look like Cueball and Megan as well) are standing next to a box in an open field of grass. Together, Cueball and Megan fall in love, get married, and retire in old age to a porch swing, Cueball now wearing a sailor cap and Megan with hair worn just like Hairbun . Suddenly, without a word, old Cueball using his cane, leaves old Megan on the porch, even though she shouts out for him to come back. He then returns to his two friends at the box from the first panel, they are now also much older and are still standing beside the box. Old Cueball picks up a sheet of paper and checks off "Happiness", the third point checked off on a list entitled "Scavenger Hunt," where the other items include these two above that are checked off: Indian-Head Penny and Snake Skin, as well as the two items below that, are not yet checked off: Four-Leaf Clover and Shark Tooth. At least one more unchecked point is on the list, but it is covered by a speech bubble. So finding happiness was just one item in what is presumably the longest-running scavenger hunt of all-time, considering Cueball grew significantly old during the hunt. The comic ends with Cueball asking, "What's next?" The list indicates this is a hunt for somewhat rare items. The US Indian Head cent (penny) was produced from 1859 to 1909, making it somewhat rare. But this they have managed. (It may have been easier to find when the scavenger hunt started, depending on when that was; for instance, if the last panel takes place in the 2000s, and 70 years have gone by, then the treasure hunt started in the 1930s, when these pennies were still fairly common.) Also, the snake skin has been managed which may be a little easier to find if you live in areas with snakes as they shed their skin by molting. So finding such a skin would be the objective to find here. A four leaf clover is a rare variation of the common three-leaf clover. A shark tooth is not easy to obtain unless you live near a beach with souvenir shops. The title, Together , of the comic is probably a reference to the saying that you find happiness together with your loved one. Cueball could have taken many different paths to find happiness, together or separate, but he chose togetherness as a way to find happiness, which is a common theme in love stories. But happiness is not something a person finds, it is an experience, hence the need to accumulate enough experiences to determine beyond doubt that happiness was truly found. This is why he had to wait until old age before he could go back to his friends. Note that Megan is never seen together with Cueball's friends, and especially since she is not invited to go back to them to check the happiness point off, there there is no reason to assume that she was in on the game from the beginning. She was just a means to an end, which makes Cueball's actions rather cruel and questionable. The title text indicates that after all this time, the players may abandon the game due to being bored with it. It is typical for children to tire of a game before it is finished; except here, Cueball spent nearly a lifetime on just one part of this game! Building a treehouse is another example of a common childhood activity. Naturally, the intended mental image of a bunch of old men and women building a treehouse and playing in it like six-year-olds is another punchline. However, as mentioned in 212: Brain , the fantasy of constructing the perfect treehouse seems to nevertheless hold a permanent place in Randall's heart (or brain) regardless of how old he gets or how immature the ambition may seem. The idea of adults having a fort in the woods was also mentioned, rather darkly, in the title text of 219: Blanket Fort . Three of the old people look very similar to three of those standing in line in 586: Mission to Culture . And much later in 1910: Sky Spotters the two birdwatchers look very much like the old version of Cueball and Megan. Giving an old person a sailor cap was also used in 2213: How Old . [Cueball and Megan are running in a field, holding hands. They are running away from another pair which also looks like Cueball and Megan. This pair stands in the background, next to a small box. There may be something lying on top of the box, but it is difficult to see clearly. The sun is shining above them.] [Cueball and Megan are in a boat on a lake, very romantic. Cueball is speaking to Megan, illustrated with a heart.] Cueball: ♡ [Cueball and Megan sit together on a bench on a beach, watching the sunset.] [Cueball and Megan stand in front of an altar under a wedding arch, with confetti falling around them. He is wearing a butterfly and she a veil.] [Cueball and Megan, now old and wrinkled, sit together holding hands on their porch at the top of a small stair outside their house. He has a sailor cap on and Megan now wears her hair in a bun. Although the woman looks like Hairbun, and the old man is wearing a sailor cap, we can assume this is still Megan and Cueball given the juxtaposition of the preceding panel.] [The same setting is depicted but seen from the side of the house. Cueball begins walking away from Megan using his cane. He has descended from the stair. Finally, Megan speaks, and unusually there is a speech bubble, with an extra smaller bubble hanging on to it for the second sentence.] Megan: Dear? Where are you- Megan: Come back! [Cueball approaches an old couple, presumably the kids from the first panel now turned old. They seem tired, looking down all the time. The man only has hair around his neck and also a cane. The woman has long thinning hair. The box from the first panel is between Cueball and the other two. On top of it lies a piece of paper] [Same picture except that Cueball is now standing still and has picked up the paper from the box and writes on it with a pen. Again there is a speech bubble.] Cueball: Okay, [The paper is shown. It is a scavenger hunt list with at least six items. The three first items have been checked off. The last item is blocked by the speech bubble, but can be seen to be there from the check box.] Scavenger hunt: ☒ Indian-head penny ☒ Snake skin ☒ Happiness ☐ Four-leaf clover ☐ Shark tooth ☐ [covered by speech bubble] Cueball (off-panel): What's next?

Parental Trolling

Parental Trolling

https://www.xkcd.com/573

https://www.explainxkcd.com/wiki/index.php/573:_Parental_Trolling

[In a frame crossing the top border of the first panel of the comic:] The future [Cueball is sitting at a futuristic desktop computer with the curved screen and keyboard both floating above the table, and a girl with pigtails is standing behind him with a portable ultra-thin screen. She shows the screen to Cueball. On it is a man with dark hair.] Girl: Hey dad, look at this old music video. Video: We're no strangers to love... Cueball: Wow, you got me. [The girl now looks at the device.] Girl: Did your generation really use this to troll people? So lame. You know, you guys sucked at pranks. [The girl is holding the device down along her legs as Cueball turns from his computer and addresses her.] Cueball: Did we? I once raised a kid with conditioning so her speech centers shut down when she was upset. [The girl has dropped the device on the floor and is fisting her hands. Cueball has turned back and is typing on the keyboard.] Girl: What? No, you couldn't have bleegle warble yargle arrgh! Cueball: Teehee.

Set in the future, a daughter approaches her father playing a music video of Rick Astley 's " Never Gonna Give You Up ". The daughter insults her father's generation's versions of playing pranks, specifically Rickrolling . The daughter refers to this as " trolling " (part of the comics title), which is popular jargon for trying to disrupt a person or community via an action to elicit an emotional response. She then comments that Cueball's generation's trolling efforts suck. The humour is in that the dad reveals he has 'trolled' his daughter by creating a reaction in which her speech centers would shut down when she gets upset, thus eliciting an emotional response which perfectly displays his prank. This would not be possible in real life unless he messed with her brain, which would be dangerous and possibly illegal. [1] This could also be referring to how most people tend to get confused in their speech patterns when upset, meaning that the dad could in fact be trolling his daughter through her misunderstanding. In this comic, the girl holds an ultra-thin tablet, a futuristic technology when this comic was released, a year before the release of the iPad. It also shows a curved computer monitor and keyboard, both of which seem to float above the desk. The title text refers to the conflict between teenagers and adults over music and culture, with teenagers often listening to music which annoys their parents. ' Easter egg ' is a term used to describe a hidden inside joke or feature inside software. Here, the daughter has been treated like a piece of software by her father Cueball. He states that since the kids on purpose chooses music and culture that they know annoys their parents, it is a fair retaliation to build in such Easter egg responses. Many people would probably disagree on this, but maybe not so much parents with teenagers at home. [In a frame crossing the top border of the first panel of the comic:] The future [Cueball is sitting at a futuristic desktop computer with the curved screen and keyboard both floating above the table, and a girl with pigtails is standing behind him with a portable ultra-thin screen. She shows the screen to Cueball. On it is a man with dark hair.] Girl: Hey dad, look at this old music video. Video: We're no strangers to love... Cueball: Wow, you got me. [The girl now looks at the device.] Girl: Did your generation really use this to troll people? So lame. You know, you guys sucked at pranks. [The girl is holding the device down along her legs as Cueball turns from his computer and addresses her.] Cueball: Did we? I once raised a kid with conditioning so her speech centers shut down when she was upset. [The girl has dropped the device on the floor and is fisting her hands. Cueball has turned back and is typing on the keyboard.] Girl: What? No, you couldn't have bleegle warble yargle arrgh! Cueball: Teehee.

Swine Flu

Swine Flu

https://www.xkcd.com/574

https://www.explainxkcd.com/wiki/index.php/574:_Swine_Flu

[Caption:] Twitter is great for watching uninformed panics unfold live. [The comic shows a twitter search results page with "Swine flu" in the search box and a gray search button.] twitter [Swine flu] (search) [The results is displayed in a frame below the search panel:] Realtime results for Swine flu 0.05 [This next line is highlighted in yellow. Most text here and below is written in normal black font, but the underlined links in the main text is in blue. Below each tweet is a line with info and reply links etc. all in gray font. Between the yellow line and the first tweet and between each tweet is a dotted line.] 1,918 more results since you started searching. Refresh to see. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Skeeve37 : Oh god I ate pork yesterday before I knew about swine flu! Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Hanneloreec : Without duct tape I can't seal the door to keep out swine flu but I can't get duct tape without going outside! Help! Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Paulyshorefan : How long until the swine flu reaches me here in Madagascar? Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - CrackMonkey74 : Swine flu is God's punishment for the ACLU and lesbians and 9/11 and nanobots! Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Twilight7531 : I fell down the stairs and there was a crack and a jagged white thing is sticking out of my arm guys is this swine flu? Less than 10 seconds ago from twitterific ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Wigu : @Untoward : No, that sounds like syphilis, not swine flu. What did you say you did with a pig? Less than 10 seconds ago from tweetdeck ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2011Seniursrule : My Dad said flu vaccines are linked to autism, so to be safe from swine flu I'm trying to lick an autistic kid. Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - CrackMonkey74 has appeared in two earlier comics: 202: YouTube and 406: Venting .

Swine flu is a strain of the flu which can be transmitted from pigs to humans. In 2009, it was the origin of the Pandemic H1N1/09 virus , which most news stations called either "H1N1" (the subtype name) or "swine flu". Because of the ambiguous name given to it and the somewhat hazy description of the transmittal process and dangers to humans, many people were concerned about the virus in ways that weren't going to be threats. This comic pokes a bit of fun at the overreaction by users on Twitter . Randall (or someone else) seems to have created Twitter accounts for all referenced handles (that may not have already existed). Some of the handles continue their interactions with each other in later tweets. Skeeve37 is a self-described hypochondriac . The tweet exemplifies the general populace's over-concern with the "animal themed" pandemics. Similarly after the bird flu scare, people avoided eating chicken. Hanneloreec is a self-described "young lady who is concerned about many things". She is a reoccurring character in the webcomic Questionable Content by Jeph Jacques, who also manages her twitter handle. Paulyshorefan 's tweet is a reference to the flash game " Pandemic 2 ", in which players try to create a disease that infects the whole world. Madagascar is the most difficult country to infect, as it only has 1 port and often closes it at the slightest hint of an infection. The difficulty of infecting Madagascar has caused it to become a meme . The user's Twitter handle is a reference to Pauly Shore , a comedian who was briefly popular in the 1990s before quickly becoming out of favor and derided as unfunny. CrackMonkey74 's tweet is a parody of viral Christian(?) messages that say that current tragedies are God's punishment, despite the fact that the Bible says that the end is not yet to come. More specifically, Crackmonkey74 blames the ACLU , lesbians (a reference to the current culture wars that give big press towards proponents of same-sex marriage against fundamentalist Christians), 9/11 (the day when the Twin Towers fell, causing controversy on whether Muslim terrorists crashed their planes on the towers or whether the government staged this by purposefully demolishing the towers) and nanobots (possibly a reference towards the highly promising but still relatively not understood field of nanotechnology, plus another reference towards the phrase "playing God"). He is likely the same Crackmonkey74 from 406: Venting and 202: YouTube . Twilight7531 's tweet implies that she got a bone fracture which ended up protruding from her arm. However, she seems to lack medical knowledge, so she is worried that her fracture is actually swine flu (though how she can be typing with a broken arm is confusing). Wigu 's tweet is a reply towards Untoward 's. Given the context, Untoward seems to have "gotten intimate" with a pig (since syphilis is a venereal disease). Given the fact that Untoward got sick because of a pig, Untoward seems to have concluded that he got swine flu. The last comment by 2011Seniorsrule references a medical paper published by the journal The Lancet , in which it is proposed that autism is caused by vaccination . Since then, the paper was partially retracted in 2004, and fully retracted in 2010 because of conflicts of interest. The entire incident has been defined as the MMR vaccine controversy . This stance has still been seen since the retraction of the paper, and still holds some popularity by cranks , quacks , pseudoscientists , and conspiracy theorists alike who are convinced that the CDC is hiding vital data that proves vaccines cause autism . The most famous figure in support of it is Jenny McCarthy . This Twitter user is not only using a debunked study about a completely different set of vaccines, they have also confused cause and effect (i.e. even if vaccines caused autism, that doesn't mean that autistic people carry flu vaccines). Also, licking vaccinated people isn't how vaccines are administered. On top of that, fear of germs and/or hypersensitivity is common among autistic people, so "licking an autistic kid" may be a difficult and possibly painful experience for the lickee. (By contrast, allistic children are well known to enjoy being licked.) The title text at first states the fact that some flu symptoms are actually the symptoms of the body's reaction, and can in some cases be more dramatic than the initial infection. E.g. A fever is a defense mechanism of the body against a disease. Then the title text makes the recommendation, to protect oneself from an overreaction by living an unhealthy life. This is not a good advice. [ citation needed ] [Caption:] Twitter is great for watching uninformed panics unfold live. [The comic shows a twitter search results page with "Swine flu" in the search box and a gray search button.] twitter [Swine flu] (search) [The results is displayed in a frame below the search panel:] Realtime results for Swine flu 0.05 [This next line is highlighted in yellow. Most text here and below is written in normal black font, but the underlined links in the main text is in blue. Below each tweet is a line with info and reply links etc. all in gray font. Between the yellow line and the first tweet and between each tweet is a dotted line.] 1,918 more results since you started searching. Refresh to see. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Skeeve37 : Oh god I ate pork yesterday before I knew about swine flu! Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Hanneloreec : Without duct tape I can't seal the door to keep out swine flu but I can't get duct tape without going outside! Help! Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Paulyshorefan : How long until the swine flu reaches me here in Madagascar? Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - CrackMonkey74 : Swine flu is God's punishment for the ACLU and lesbians and 9/11 and nanobots! Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Twilight7531 : I fell down the stairs and there was a crack and a jagged white thing is sticking out of my arm guys is this swine flu? Less than 10 seconds ago from twitterific ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Wigu : @Untoward : No, that sounds like syphilis, not swine flu. What did you say you did with a pig? Less than 10 seconds ago from tweetdeck ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2011Seniursrule : My Dad said flu vaccines are linked to autism, so to be safe from swine flu I'm trying to lick an autistic kid. Less than 10 seconds ago from web ∙ reply ∙ view tweet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - CrackMonkey74 has appeared in two earlier comics: 202: YouTube and 406: Venting .

Tag Combination

Tag Combination

https://www.xkcd.com/575

https://www.explainxkcd.com/wiki/index.php/575:_Tag_Combination

[Cueball and Megan are talking.] Cueball: So you can come up with a song title fitting any tag combination? Megan: Try me. [Cueball and Megan are talking.] Cueball: Lesbian voyeurism one-hit wonder mash-up. Megan: "I wish that Stacey's Mom had Jessie's Girl." [Cueball and Megan are just standing there for a beat panel.] [Cueball and Megan are talking.] Cueball: Well, that was one, but- Megan: "When you Come On Eileen I touch myself." Cueball: Okay, wow. Both song names that Megan produces are in iambic pentameter , suggesting that Megan's hobby has the flavor of Cueball's in 79: Iambic Pentameter .

Song tags are a form of file metadata used to categorize music. Tags will typically describe the content and genre of the song, and many music organization programs and services will allow users to find all songs that contain a particular tag; so when a user searches for "Country breakup music," they will receive a list of country songs about breaking up. In this comic, Cueball tests Megan 's claim that she can make a song name for any set of tags by coming up with a collection of mostly unrelated words: " lesbian voyeurism one-hit wonder mash-up ." A lesbian is a woman who is only sexually interested in other women. Voyeurism is the act of watching someone else do something sexual, generally without their knowledge. A one-hit wonder is a band that had "one big hit" before fading from the public eye forever. A mash-up is when someone takes two previously unrelated songs and makes a third song that's a mix of both of them (a recent example of which would be this Gangam Style/Ghostbusters theme mashup ). In response, Megan immediately replies with one song title that looks like it would fit the tags well. When Cueball asks for a second example, Megan gives him a new example for the same set of tags, which is really impressive. Megan's first title, "I Wish That Stacy's Mom Had Jessie's Girl" is a mash-up of "Jessie's Girl" by Rick Springfield (see video on YouTube), and "Stacy's Mom" by Fountains of Wayne (see video on YouTube), the latter was a one-hit-wonder , whereas Springfield has had several other hits. (The song Stacy's Mom was referenced in comic 61: Stacey's Dad ). The second title, "When You Come on Eileen I Touch Myself" is a mash-up of "Come on Eileen" by Dexys Midnight Runners (see video on YouTube), and "I Touch Myself" by Divinyls (see video on YouTube). Both of these are one-hit wonders (and can both be found on this list of such songs). Note that "Come on, Eileen" means "Hurry up, Eileen", and that "to come on someone" means to ejaculate on someone. Since the song is about lesbian sex, come on someone must mean have an orgasm while being on someone. For other random connections see 305: Rule 34 . The title text is a set of potential lyrics to Megan's second title. Randall borrowed the rhyme scheme, phrasing, and subject matter from the first eight stanzas of "I Touch Myself" with additional subject matter inspired by "Come on Eileen." The final stanza is the chorus lead-in from the latter. The lyrics suggest a changed relationship between the characters. In the original "I Touch Myself", the female singer touches herself (masturbates) when thinking about her lover (of unspecified gender); instead, she now does this while a new third character makes love to her beloved, Eileen, while the singer overhears them (as a voyeur) from the apartment above. Here are the lyrics for I Touch Myself and Come on Eileen . Below in the table the mashed up lines are shown. As can be seen most of the text is from "I Touch Myself": [Cueball and Megan are talking.] Cueball: So you can come up with a song title fitting any tag combination? Megan: Try me. [Cueball and Megan are talking.] Cueball: Lesbian voyeurism one-hit wonder mash-up. Megan: "I wish that Stacey's Mom had Jessie's Girl." [Cueball and Megan are just standing there for a beat panel.] [Cueball and Megan are talking.] Cueball: Well, that was one, but- Megan: "When you Come On Eileen I touch myself." Cueball: Okay, wow. Both song names that Megan produces are in iambic pentameter , suggesting that Megan's hobby has the flavor of Cueball's in 79: Iambic Pentameter .

Packages

Packages

https://www.xkcd.com/576

https://www.explainxkcd.com/wiki/index.php/576:_Packages

[Cueball is sitting at his computer.] Cueball: I love getting packages. [Megan enters and Cueball turns towards her.] Cueball: I set up a script to search eBay et. al. for $1 items with free shipping. [Cueball comes home with a backpack on his back and find a package waiting for him on his doorstop.] Cueball: I gave it $365, so each day it can buy me something random. [Cueball, again sitting at his computer.] Megan (off-screen): What if you just end up with lots of crap? Cueball: I'll give it away. Cueball: But I'm sure I'll end up with some interesting stuff. [The next five panels have a caption in a black frame at the top. The caption is written first for each panel. In the first panel Cueball has unpacked a hose. The paper lies in tatters on the floor. Megan stands next to him.] Day 1: Length of rubber hose Cueball: Could be handy around the house. [Cueball stands with a black item and the packaging material it came in. Megan looks on.] Day 2: Ski mask Cueball: It's spring, but hey. [Cueball is standing alone with a bear trap and the box it came in on the floor.] Day 3: Bear trap Cueball: Huh. [Megan is back as Cueball looks at a piece of paper that came in an envelope.] Day 4: Tourist map of the Pentagon. Megan: Uh oh. [Cueball is standing alone with a bottle of lube in one hand and the box it came in in the other hand.] Day 5: Lube Cueball: I'm stopping this before I end up on every F.B.I. watch list ever. Someone has set up an actual service inspired by this comic, which does exactly what this comic describes, and has been featured in the advertisements section to the left.

Cueball wrote a script that searches online shopping sites for items that cost US$1 with free shipping. Because the script is programmed to use an account with a $365 balance, this script will buy one random item per day for a full year. Megan comments that Cueball might just end up with "lots of crap" but he replies that he might get something interesting. Over five days the script orders a length of rubber hose, a ski mask, a bear trap, a map of The Pentagon and "lube" (sexual lubrication). This pattern prompts Cueball to stop the script out of fear of being placed on a FBI watch list; to a paranoid passerby, the purchased items make Cueball look like a terrorist who plans to kidnap and torture federal employees. And also a pervert; such a contrast is considered funny. In the title text a sixth item is sent, a bobcat . This is probably connected with 325: A-Minus-Minus where Black Hat delivered a bobcat instead of a chair. [Cueball is sitting at his computer.] Cueball: I love getting packages. [Megan enters and Cueball turns towards her.] Cueball: I set up a script to search eBay et. al. for $1 items with free shipping. [Cueball comes home with a backpack on his back and find a package waiting for him on his doorstop.] Cueball: I gave it $365, so each day it can buy me something random. [Cueball, again sitting at his computer.] Megan (off-screen): What if you just end up with lots of crap? Cueball: I'll give it away. Cueball: But I'm sure I'll end up with some interesting stuff. [The next five panels have a caption in a black frame at the top. The caption is written first for each panel. In the first panel Cueball has unpacked a hose. The paper lies in tatters on the floor. Megan stands next to him.] Day 1: Length of rubber hose Cueball: Could be handy around the house. [Cueball stands with a black item and the packaging material it came in. Megan looks on.] Day 2: Ski mask Cueball: It's spring, but hey. [Cueball is standing alone with a bear trap and the box it came in on the floor.] Day 3: Bear trap Cueball: Huh. [Megan is back as Cueball looks at a piece of paper that came in an envelope.] Day 4: Tourist map of the Pentagon. Megan: Uh oh. [Cueball is standing alone with a bottle of lube in one hand and the box it came in in the other hand.] Day 5: Lube Cueball: I'm stopping this before I end up on every F.B.I. watch list ever. Someone has set up an actual service inspired by this comic, which does exactly what this comic describes, and has been featured in the advertisements section to the left.

The Race Part 1

The Race: Part 1

https://www.xkcd.com/577

https://www.explainxkcd.com/wiki/index.php/577:_The_Race:_Part_1

Megan: Huh, cool. Nathan Fillion (Mal from Firefly) has an electric skateboard. Just like you! [Cueball leaves the room.] Megan: Did you hear that? Nathan- Sounds from off-screen: Ratchet Zip Buckle [Cueball returns wearing helmet, knee pads, elbow pads, sunglasses and holding his electric skateboard.] Cueball: I heard. Gimme the computer. I need to book a flight. [Caption in a black frame at the bottom of the last panel:] To be continued...

This is possibly a continuation of 139: I Have Owned Two Electric Skateboards . Firefly was a television series aired by Fox in 2002 that got cancelled mid-way through, but it has a large fan base nowadays (for a more comprehensive explanation, see the Wikipedia page). The star of the show was Captain Malcolm (or Mal) Reynolds, played by Nathan Fillion . So in this comic, Megan tells Cueball that Nathan Fillion has an electric skateboard. Cueball immediately starts planning a trip to visit and race Nathan Fillion. The title text refers to an earlier comic 211: Hamster Ball Heist , where Cueball kidnaps Wayne Coyne in his hamster ball. All comics in " The Race " series: This series was released on five consecutive days (Monday-Friday) and not over the usual Monday/Wednesday/Friday schedule. Electric skateboards have been the subject of several other comics like 139: I Have Owned Two Electric Skateboards , 409: Electric Skateboard (Double Comic) and a panel in 442: xkcd Loves the Discovery Channel . Megan: Huh, cool. Nathan Fillion (Mal from Firefly) has an electric skateboard. Just like you! [Cueball leaves the room.] Megan: Did you hear that? Nathan- Sounds from off-screen: Ratchet Zip Buckle [Cueball returns wearing helmet, knee pads, elbow pads, sunglasses and holding his electric skateboard.] Cueball: I heard. Gimme the computer. I need to book a flight. [Caption in a black frame at the bottom of the last panel:] To be continued...

The Race Part 2

The Race: Part 2

https://www.xkcd.com/578

https://www.explainxkcd.com/wiki/index.php/578:_The_Race:_Part_2

[Cueball with skateboard and gear and Megan are talking.] Cueball: "Why race him?" He's Captain Reynolds! Megan: Mr. Fillion is an actor. Firefly was years ago. [They go over to a computer; Cueball is using a phone and presumably looking up a phone number.] Megan: He has his own life to live, and I'm sure the last thing he wants to do is indulge a fan by playing Mal for him. Meanwhile... [Nathan Fillion is standing in front of a mirror in a trenchcoat.] Nathan: (into the mirror) Name's Captain Reynolds, ma'am. *ahem* Name's Captain Reynolds, ma'am. Someone offpanel: Nathan? Telephone! Nathan: That's Captain! Someone offpanel: Fine, Captain Nathan. Nathan: No, use my space name! Someone offpanel: *sigh* [Nathan and Cueball talk on the phone.] Cueball: So, how about we race for charities? Nathan: Sure. Always did want a charity of my own. Cueball (between panels): Come again? Nathan: You know, boxes in supermarkets collecting food. 'Course, ought to tack up a list sayin' which wines I like best... Cueball: Uh, that's not quite— Nathan (over the phone): Listen, I'm the captain here. Cueball: ...I just got goosebumps when you said that. Nathan: Yeah, happens to me too whenever I get captainy. I cut such a strapping figure. Nathan: Buckle! Swash! Nathan: All right, let's do this race.

Firefly was a television series aired by Fox in 2002. The star of the show was Captain Malcolm "Mal" Reynolds , played by Nathan Fillion . Megan tries to play the rational card, and insist that the characters of major TV shows must get tired of fans' never-ending need to see them playing that character, and never being themselves. Nathan Fillion, however, appears to miss the days of Firefly so much that he spends his time reenacting his role as Malcolm at home. In the fourth panel Cueball suggests they race for charities, which would mean the winner gets to donate the prize money to their charity of choice. In the fifth panel Fillion, takes the phrase and twists it to mean that the winner gets the charity. This is why Cueball says the confused line "Come again?" The title text refers both to Mal being referred to by Kaylee as "Captain Tightpants" in the episode "Shindig" , and to Captain Hammer, a superhero played by Nathan Fillion in Dr. Horrible's Sing-Along Blog , another series created by Joss Whedon . "Hammerpants" may also be a reference to the odd, puffy parachute pants worn by 1990s rapper MC Hammer. All comics in " The Race " series: This series was released on five consecutive days (Monday-Friday) and not over the usual Monday/Wednesday/Friday schedule. Electric skateboards have been the subject of several other comics like 139: I Have Owned Two Electric Skateboards , 409: Electric Skateboard (Double Comic) and a panel in 442: xkcd Loves the Discovery Channel . [Cueball with skateboard and gear and Megan are talking.] Cueball: "Why race him?" He's Captain Reynolds! Megan: Mr. Fillion is an actor. Firefly was years ago. [They go over to a computer; Cueball is using a phone and presumably looking up a phone number.] Megan: He has his own life to live, and I'm sure the last thing he wants to do is indulge a fan by playing Mal for him. Meanwhile... [Nathan Fillion is standing in front of a mirror in a trenchcoat.] Nathan: (into the mirror) Name's Captain Reynolds, ma'am. *ahem* Name's Captain Reynolds, ma'am. Someone offpanel: Nathan? Telephone! Nathan: That's Captain! Someone offpanel: Fine, Captain Nathan. Nathan: No, use my space name! Someone offpanel: *sigh* [Nathan and Cueball talk on the phone.] Cueball: So, how about we race for charities? Nathan: Sure. Always did want a charity of my own. Cueball (between panels): Come again? Nathan: You know, boxes in supermarkets collecting food. 'Course, ought to tack up a list sayin' which wines I like best... Cueball: Uh, that's not quite— Nathan (over the phone): Listen, I'm the captain here. Cueball: ...I just got goosebumps when you said that. Nathan: Yeah, happens to me too whenever I get captainy. I cut such a strapping figure. Nathan: Buckle! Swash! Nathan: All right, let's do this race.

The Race Part 3

The Race: Part 3

https://www.xkcd.com/579

https://www.explainxkcd.com/wiki/index.php/579:_The_Race:_Part_3

[Nathan, Cueball, and Summer Glau standing around with electric skateboards.] Nathan: Meet a few of my friends. This is- Cueball: Summer Glau! You were the best part of Chronicles . Summer: I eat my bodyweight in food every 31 days. That's slightly faster than the human average. [Summer stares off into space.] Nathan: Yeah, there's a reason she only plays strange roles. Cueball: Ah. Summer (from below): I'm part of the floor now. [They find Jewel Staite working on a skateboard's engine.] Nathan: And this is Kaylee. Jewel: My name is Jewel, Nathan. Nathan: Kaylee— Jewel: Jewel . Nathan: —Jewel is fixin' up my new board. Jewel: Almost done! Cueball: So wait. Summer's actually weird, Jewel's actually a mechanical whiz... Cueball: ...will Morena Baccarin be here? Is she really a— Nathan and Jewel: No. The racers set up [Nathan and Jewel are to the far left of a full-width panel. Nathan is standing on his skateboard holding a controller. Cueball is on his skateboard which is careening out of control on the far right of the panel.] Nathan: Kaylee, I've been gunnin' the radio hand throttle thingy for a while, but it ain't movin'. Jewel: Oh, I must've set it to the wrong frequency! Cueball (riding around on haywire board): AAAAAAAA

Firefly was a television series aired by Fox in 2002 that got cancelled midway through, but it has a large fan base nowadays (for a more comprehensive explanation, see the Wikipedia page). The star of the show was Captain Malcolm (or Mal) Reynolds, played by Nathan Fillion . Other members of his crew were Kaylee (played by Jewel Staite ), the ship's mechanic, Inara Serra (played by Morena Baccarin ) was a Companion (or, as Mal would say: whore) that helped Serenity (the spaceship) gain a landing on many planets that otherwise would have nothing to do with Mal. River Tam (played by Summer Glau ) was the seemingly crazy younger sister of Dr. Simon Tam (played by Sean Maher ), and due to her latent psionic powers and the damage from the experiments she had undergone, she was known for making odd, out-of-context statements. When Cueball is introduced to the first two women, he learns that they behave in real life as on the Firefly show (Summer is strange and Jewel is a mechanical wiz) - this is why he begins to ask about Morena Baccarin, and also why the other two says no. before he can finish the question is she really a prostitute ? In the last panel, Kaylee apparently wired up Mal's controller to broadcast on the frequency of Cueball's skateboard, so it took control of his board, where Mal's stood still. (Buy a few RC models ( Radio-controlled model ) to play with friends and inevitably this will happen. Where two controllers broadcast on the same frequency, so the two models are confused by the signals they receive.) Terminator: The Sarah Connor Chronicles was a television series aired by Fox from 2008-09. Summer Glau played the role of Cameron, a Terminator; Cameron was played in a distinctly "strange" manner as a humanoid robot who finds much about humanity puzzling. Combined with her role as River Tam, the joke is that it wasn't Summer's characters who were eccentric, but that Summer Glau herself is actually just as strange and eccentric as she is shown to be on screen. All comics in " The Race " series: This series was released on five consecutive days (Monday-Friday) and not over the usual Monday/Wednesday/Friday schedule. Electric skateboards have been the subject of several other comics like 139: I Have Owned Two Electric Skateboards , 409: Electric Skateboard (Double Comic) and a panel in 442: xkcd Loves the Discovery Channel . [Nathan, Cueball, and Summer Glau standing around with electric skateboards.] Nathan: Meet a few of my friends. This is- Cueball: Summer Glau! You were the best part of Chronicles . Summer: I eat my bodyweight in food every 31 days. That's slightly faster than the human average. [Summer stares off into space.] Nathan: Yeah, there's a reason she only plays strange roles. Cueball: Ah. Summer (from below): I'm part of the floor now. [They find Jewel Staite working on a skateboard's engine.] Nathan: And this is Kaylee. Jewel: My name is Jewel, Nathan. Nathan: Kaylee— Jewel: Jewel . Nathan: —Jewel is fixin' up my new board. Jewel: Almost done! Cueball: So wait. Summer's actually weird, Jewel's actually a mechanical whiz... Cueball: ...will Morena Baccarin be here? Is she really a— Nathan and Jewel: No. The racers set up [Nathan and Jewel are to the far left of a full-width panel. Nathan is standing on his skateboard holding a controller. Cueball is on his skateboard which is careening out of control on the far right of the panel.] Nathan: Kaylee, I've been gunnin' the radio hand throttle thingy for a while, but it ain't movin'. Jewel: Oh, I must've set it to the wrong frequency! Cueball (riding around on haywire board): AAAAAAAA

The Race Part 4

The Race: Part 4

https://www.xkcd.com/580

https://www.explainxkcd.com/wiki/index.php/580:_The_Race:_Part_4

[Cueball and Nathan Fillion are ready on the start line on their electric skateboards.] Voice off panel: On your mark... Voice: Get set... Nathan: Remember episode 11, when I got all naked in that desert? Voice: Go! [Nathan speeds away leaving Cueball standing at the start line.] Voice: ...I said "Go." Voice: Someone throw some water on him. Cueball: Can't...get it...out of my head... [Nathan on walkie talkie, speeding on his skateboard.] Nathan: He's right behind me. Kaylee, I'm gonna try a Crazy Ivan. Jewel [on walkie talkie] ( 579 shows Nathan's naming confusion): That doesn't make any sense, Nathan. Nathan: Trust me. Jewel: No, I mean it's not a skateboard maneuver. The concept doesn't even apply to this situation. Nathan [via walkie talkie]: That's why it just might work! Jewel: No, that's the opposite of true! Nathan: On my mark, override the remote differential and throw her into a spin. Jewel [via walkie talkie]: okay, but— Nathan: Mark! WHAM [Nathan lying injured on the ground next to his skateboard, Cueball cruises past.] Whirrrrrrrr [Nathan, trying to stand up.] Nathan: I'm down. Tell Summer "The chickens are in the hayloft. Plan Gamma is a go." [Nathan, one foot on skateboard, looking at walkie talkie.] mumbling from walkie talkie Jewel: She says, "Plan gamma acknowledged. The meerkats are in the bag. [Summer Glau is walking off panel.] Jewel [to walkee talkie]: So we're good? Nathan: Hard to tell with her. Do you see an actual bag of meerkats? Jewel: No. Nathan: Then we're probably good. [Cueball screeching to a halt as he sees Summer Glau.] Cueball: Oh! Hi, Miss Glau! I'd love to talk, but Nathan's back on his feet and catching up. [Summer grabs Cueball's arm.] Grab Cueball: Wha— [Summer kicks Cueball in the face whilst pulling his arm towards her, he flies off his skateboard.] [Summer walking away as Cueball lies crippled on the floor with his sunglasses beside him.] [Cueball still lying on the floor.] Cueball [thinking]: I've never been so turned on in my life.

Firefly was a television series aired by Fox in 2002, but it was canceled after only fourteen episodes had been produced. Over ten years later, it still has a devoted fan base, apparently including Randall . The main characters were the crew of the spaceship "Serenity", including Captain Malcolm "Mal" Reynolds ( Nathan Fillion ), mechanical genius Kaywinnet Lee "Kaylee" Frye ( Jewel Staite ), the apparently insane psychic River Tam ( Summer Glau ), and six others not mentioned in this comic. Nathan Fillion appeared naked at the beginning and end of the show's eleventh episode, "Trash", after having been stripped of all his weapons, equipment, and clothes in a desert. Cueball is mentally overloaded by this image (either aroused or repulsed it is hard to say) to the extent that he misses the start signal. Worried about his pursuer, Nathan wants to perform a Crazy Ivan , an emergency maneuver used by the crew of Serenity in the pilot episode of the series to escape the hot pursuit of a Reaver ship. It involves a 180° spin turn followed by rapid acceleration towards (and hopefully past) the pursuer, which does not have the ability to make such a rapid turn. In a Firefly -class vessel, it is performed by temporarily reversing the direction of thrust of one of the two atmospheric engines, achieved by physically rotating the engine nacelle. The name of the maneuver is taken from the antics of Soviet submarines in trying to detect (not to evade) enemy submarines hiding in the sonar blind-spot directly behind their vessel. In reality, sharp turns suffice for this purpose; it is not necessary to completely reverse direction. The name entered popular culture after being used in the movie The Hunt For Red October . Nathan appears to understand exactly what will happen. He asks Jewel to "override the remote differential ", implying that the two driven wheels could then be powered in opposite directions, causing a spin-turn. As Jewel points out, this will be unlikely to have the intended effect. Nathan is much heavier than his vehicle, and he is not securely attached to it. Momentum is his enemy. Even if it were successful, it would be utterly pointless, because he would find himself heading away from the finish line. Cueball is only pursuing him with the intent to overtake him, and the Crazy Ivan guarantees that this will happen. Summer Glau is often a target of sexual attraction for her appearance and her well-known, eccentric characters. River Tam, in the movie Serenity , had subconscious programming that caused her to be able to take on dozens of foes in hand-to-hand combat, and her Terminator character in The Sarah Connor Chronicles also regularly beat on men far larger than her, which, for many, just adds to the attraction. Thus, even as Summer fells him with a devastating kick to the face, Cueball is incredibly aroused. The title text refers to a common ability in fiction for characters to come up with an idea that is 'just crazy enough to work'. In real-life situations (such as an electric skateboard race), people are rarely able to come up with an idea that is just out-of-the-ordinary enough to work perfectly, and in their attempts to do so, will come up with an idea that will instead absolutely fail to work (and make them look like fools to boot). All comics in " The Race " series: This series was released on five consecutive days (Monday-Friday) and not over the usual Monday/Wednesday/Friday schedule. Electric skateboards have been the subject of several other comics like 139: I Have Owned Two Electric Skateboards , 409: Electric Skateboard (Double Comic) and a panel in 442: xkcd Loves the Discovery Channel . [Cueball and Nathan Fillion are ready on the start line on their electric skateboards.] Voice off panel: On your mark... Voice: Get set... Nathan: Remember episode 11, when I got all naked in that desert? Voice: Go! [Nathan speeds away leaving Cueball standing at the start line.] Voice: ...I said "Go." Voice: Someone throw some water on him. Cueball: Can't...get it...out of my head... [Nathan on walkie talkie, speeding on his skateboard.] Nathan: He's right behind me. Kaylee, I'm gonna try a Crazy Ivan. Jewel [on walkie talkie] ( 579 shows Nathan's naming confusion): That doesn't make any sense, Nathan. Nathan: Trust me. Jewel: No, I mean it's not a skateboard maneuver. The concept doesn't even apply to this situation. Nathan [via walkie talkie]: That's why it just might work! Jewel: No, that's the opposite of true! Nathan: On my mark, override the remote differential and throw her into a spin. Jewel [via walkie talkie]: okay, but— Nathan: Mark! WHAM [Nathan lying injured on the ground next to his skateboard, Cueball cruises past.] Whirrrrrrrr [Nathan, trying to stand up.] Nathan: I'm down. Tell Summer "The chickens are in the hayloft. Plan Gamma is a go." [Nathan, one foot on skateboard, looking at walkie talkie.] mumbling from walkie talkie Jewel: She says, "Plan gamma acknowledged. The meerkats are in the bag. [Summer Glau is walking off panel.] Jewel [to walkee talkie]: So we're good? Nathan: Hard to tell with her. Do you see an actual bag of meerkats? Jewel: No. Nathan: Then we're probably good. [Cueball screeching to a halt as he sees Summer Glau.] Cueball: Oh! Hi, Miss Glau! I'd love to talk, but Nathan's back on his feet and catching up. [Summer grabs Cueball's arm.] Grab Cueball: Wha— [Summer kicks Cueball in the face whilst pulling his arm towards her, he flies off his skateboard.] [Summer walking away as Cueball lies crippled on the floor with his sunglasses beside him.] [Cueball still lying on the floor.] Cueball [thinking]: I've never been so turned on in my life.

The Race Part 5

The Race: Part 5

https://www.xkcd.com/581

https://www.explainxkcd.com/wiki/index.php/581:_The_Race:_Part_5

[Nathan skates in.] Nathan: So you took care of him? Summer: I can extrude hair, but I can't retract it. Nathan: That a yes? [Summer grabs Nathan's arm as he skates past her, pulling him off the board.] Nathan: Bwah! [An Andy Capp-esque meleè dust cloud.] WHAP BAM POW WHAM [Summer skates away.] [A beat-up Nathan approaches an similarly battered Cueball.] Nathan: She may have my board, but I can still beat you to the finish line if I bring you down. Cueball: Bring it, Captain Tightpants. Nathan: I've got nothing to bring. I just said that so she could get behind you. [Cueball turns.] Cueball: Who— [Cueball is hit with his board.] WHAM [Nathan stands over a prone Cueball.] Nathan: I just said that so I could get behind you. The serious fans always fall for the quotes. [Wide panel of Summer crossing the finishing line on Nathan's board, breaking through the tape.] Announcer: And the winner is... Off-screen voice: Summer Glau? Summer: I swallowed a bug again. [Close-up of Cueball's beaten face.] Cueball: All right, Fillion. I've had enough of your treachery and ...rugged good looks. This ends here. [Equally close-up: Nathan's face, bearing several grazes.] Nathan: All right, fanboy. Let this be our final battle. [They rush at each other, fists ready to swing punches.] Final battle canceled by Fox. Try an Internet petition drive - those totally work.

This is a continuation of the previous comic in " The Race " series, 580: The Race: Part 4 . In panel 6 (2nd panel in the 2nd row), Nathan Fillion line is reminiscent of a similar quote from the 2nd episode of Firefly , The Train Job : "I just wanted you to face me so she could get behind ya." In the show, Malcolm Reynolds is aided by Zoë Washburne , his second in command, who gets behind the bar thug he is speaking to. In the comic, Nathan Fillion is using the line on a fan, but Gina Torres is not standing behind Cueball this time. Summer's line about growing but not retracting her hair appears to mean that because Nathan used her to stop Cueball, she has to stop him as well, which she neatly does. Alternatively, the line may be a random non-sequitur of the sort often uttered by her neurologically damaged character in the Firefly 'verse. "Bwah!" is a sound Malcolm makes during one episode in which one of his crewmembers inadvertently sneaks up on him while trying to ask him a question. When he is questioned about it, he says he has invented a new war cry, and promptly practices yelling 'Bwahhhh' in a confident manner while readying his pistol. Summer's statement in the 10th panel about swallowing a bug is a reference to the movie Serenity , made in 2005 to conclude Firefly's storyline. After a harrowing high-speed chase in an open-topped hovercraft, the only comment from Summer's character is "I swallowed a bug," showing that she was either unconcerned, or stunned, by the narrow escape. The final panel is a reference to Fox Television 's treatment of Firefly . Firefly was cancelled after only 11 episodes of the 14 made were aired, leaving three episodes unaired. Internet petitions, contrary to the sarcastic suggestion in the final panel, pretty much never work. All comics in " The Race " series: This series was released on five consecutive days (Monday-Friday) and not over the usual Monday/Wednesday/Friday schedule. Electric skateboards have been the subject of several other comics like 139: I Have Owned Two Electric Skateboards , 409: Electric Skateboard (Double Comic) and a panel in 442: xkcd Loves the Discovery Channel . [Nathan skates in.] Nathan: So you took care of him? Summer: I can extrude hair, but I can't retract it. Nathan: That a yes? [Summer grabs Nathan's arm as he skates past her, pulling him off the board.] Nathan: Bwah! [An Andy Capp-esque meleè dust cloud.] WHAP BAM POW WHAM [Summer skates away.] [A beat-up Nathan approaches an similarly battered Cueball.] Nathan: She may have my board, but I can still beat you to the finish line if I bring you down. Cueball: Bring it, Captain Tightpants. Nathan: I've got nothing to bring. I just said that so she could get behind you. [Cueball turns.] Cueball: Who— [Cueball is hit with his board.] WHAM [Nathan stands over a prone Cueball.] Nathan: I just said that so I could get behind you. The serious fans always fall for the quotes. [Wide panel of Summer crossing the finishing line on Nathan's board, breaking through the tape.] Announcer: And the winner is... Off-screen voice: Summer Glau? Summer: I swallowed a bug again. [Close-up of Cueball's beaten face.] Cueball: All right, Fillion. I've had enough of your treachery and ...rugged good looks. This ends here. [Equally close-up: Nathan's face, bearing several grazes.] Nathan: All right, fanboy. Let this be our final battle. [They rush at each other, fists ready to swing punches.] Final battle canceled by Fox. Try an Internet petition drive - those totally work.

Brakes

Brakes

https://www.xkcd.com/582

https://www.explainxkcd.com/wiki/index.php/582:_Brakes

Of the potential responses to my brakes' failure, I did not choose the best. [A cliff is visible, with a car flying off it, and trees below.] Voice from car: Hello, you're on Car Talk.

A car's brakes fail on a winding mountain road. As a response, the driver calls a live radio phone-in show, overlooking the fact that he is in immediate danger and has no time to gather outside advice before improvising a solution. The driver loses control of the car and plunges over a cliff. If this ever happens to you, http://www.wikihow.com/Stop-a-Car-with-No-Brakes The title text refers to Tom and Ray Magliozzi who were the co-hosts of the weekly radio show Car Talk . It was a car advice/comedy radio show often aired on NPR stations. While there is some actual advice given on the radio show, it's presented as a comedy/entertainment show. Much of the show did involve the hosts "gasping and hacking" as they ask non-relevant questions of the callers and add their own commentary or relate other personal asides and stories. Since he claims that he has 6.5 funny seconds, he must have connected with them way before going over the cliff. Because in 6.5 seconds a car would fall approximately 200 m (½*g*t^2, with g = 9.81 m/s^2, and t the time in seconds. This will give 207 m, but there will be a lot of air resistance). It is clear from the drawing that the car is still going almost straight out into the air, so it is still almost at the height where it left the road at quite a high speed (to get this far away without turning the engine down towards earth yet.) And the front of the car is just about 5 car lengths to the ground, which would make this a 10-15 m drop only (which would take less than 2 seconds to fall). But according to the comic it seems like he first connected with the show, just when the car has left the road... Of the potential responses to my brakes' failure, I did not choose the best. [A cliff is visible, with a car flying off it, and trees below.] Voice from car: Hello, you're on Car Talk.

CNR

CNR

https://www.xkcd.com/583

https://www.explainxkcd.com/wiki/index.php/583:_CNR

[Megan is sitting at a computer.] Computer: Speech2Text Commander Computer: Bug #167801 Computer: Speech recognition fails on young child voices. Megan: Hmm. [The view enlarges to show a man sitting at another desk.] Megan: Hey, can you do me without a condom? We need a young child for something. Cueball: Okay. [A pregnancy test is displayed. The label indicates not pregnant.] Pregnant Not pregnant [Megan is typing on the computer.] Megan typing: Bug #167801 Megan typing: Status: Closed Megan typing: Reason: Could not reproduce.

"Could not reproduce" (CNR as per the title) is used here as a double entendre . Because the reported bug is that speech recognition failed on a young child's voice, the programmers attempt to reproduce (biologically) in order to have a child to use as a test subject to understand and fix the bug, starting by reproducing it (the bug). However the attempt fails, as shown by the negative pregnancy test, and therefore the bug report is closed with the reason being "could not reproduce": they could not reproduce the bug because they could not reproduce biologically. Nowadays, developers of software usually have a centralized repository of bugs which generally uses one of a handful of standard interfaces for tracking problems and desired features in software. There is usually a quick way of removing pending items from this system by changing the status to closed and selecting a reason from perhaps a dropdown list. "Could not reproduce" is a standard reason provided in almost all of these systems, so the novel pun provides extra humor to software developers. This reason also shows up in comic 937: TornadoGuard . The secondary joke is that Megan has chosen a ridiculous method of obtaining a child for the relatively simple task of testing the software. The obvious solution is to find a pre-existing child to use; [ citation needed ] giving birth to (and, presumably, raising) a child would burden the programmers with serious expenses, health concerns, and responsibilities; and it would take years before the child would be able to speak clearly enough to use the program. The title-text "Can't and shouldn't" qualifies the bug report, meaning that the programmers not only could not reproduce, they also should not reproduce, as their reasons for doing so shows they have exceedingly bad judgment. (They also have poor child-rearing skills, as demonstrated in comic 674: Natural Parenting .) [Megan is sitting at a computer.] Computer: Speech2Text Commander Computer: Bug #167801 Computer: Speech recognition fails on young child voices. Megan: Hmm. [The view enlarges to show a man sitting at another desk.] Megan: Hey, can you do me without a condom? We need a young child for something. Cueball: Okay. [A pregnancy test is displayed. The label indicates not pregnant.] Pregnant Not pregnant [Megan is typing on the computer.] Megan typing: Bug #167801 Megan typing: Status: Closed Megan typing: Reason: Could not reproduce.

Unsatisfied

Unsatisfied

https://www.xkcd.com/584

https://www.explainxkcd.com/wiki/index.php/584:_Unsatisfied

[Cueball is holding hands with Ponytail, while he is looking at Megan to the far right.] [Below this first central panel there are two arrows that direct the comic into a pair of different paths. Beneath each of the next three double panels there is a small arrow pointing straight down.] (Left path) [Cueball has turned away from Megan (off-screen) and is now kissing Ponytail, but he is thinking about Megan.] (Right path) [Cueball walks away from Ponytail (off-screen) and reaches out to Megan, but he is thinking about Ponytail.] (Left path) [Cueball is performing cunnilingus on Ponytail, he is still thinking about Megan.] (Right path) [Cueball and Megan have sex on the arm of a chair, he is still thinking about Ponytail.] (Left path) [Cueball and Ponytail are drawing something together, and he is still thinking about Megan.] (Right path) [Cueball and Megan are hiking together, and he is still thinking about Ponytail.] (Left path) [Cueball and Ponytail are holding hands looking at each other, and he continues to think of Megan.] (Right path) [Cueball and Megan are holding hands looking at each other, and he continues to think of Ponytail.] [Below the previous two panels two longer arrows again reunite into one central panel.] [Two gravestones are next to each other. One of them (Cueball's) is thinking about a third gravestone (for the girl he did not choose).]

Cueball is trying to decide if he wants to stay with Ponytail who he is currently dating or leave her and have a relationship with Megan . The comic suggests that no matter which one he chooses he will never truly achieve happiness because of his longing for the option he chose not to take. In a sense this is a no-win situation . No matter what he does of interesting stuff (sex or otherwise) with Ponytail he will be thinking forever of Megan, and vice versa. This even goes on after he dies, where he lies next to one of them and thinks he would rather have been buried next to the other girl. The title text is referring to a concept in computer science. All comparison based sorting algorithms are incapable of sorting an arbitrary set of n values faster than an order of n*log(n). On the other hand, non-comparison sorting algorithms (e.g. bucket sort ) with external knowledge of the distribution of the values can sort them with order n. If Cueball was capable of establishing an external scale he could use a non-comparison sort, but as he does not know what the best thing for him is he is stuck with comparisons and thus he can't achieve better performance. This comic is possibly a sequel to 310: Commitment . [Cueball is holding hands with Ponytail, while he is looking at Megan to the far right.] [Below this first central panel there are two arrows that direct the comic into a pair of different paths. Beneath each of the next three double panels there is a small arrow pointing straight down.] (Left path) [Cueball has turned away from Megan (off-screen) and is now kissing Ponytail, but he is thinking about Megan.] (Right path) [Cueball walks away from Ponytail (off-screen) and reaches out to Megan, but he is thinking about Ponytail.] (Left path) [Cueball is performing cunnilingus on Ponytail, he is still thinking about Megan.] (Right path) [Cueball and Megan have sex on the arm of a chair, he is still thinking about Ponytail.] (Left path) [Cueball and Ponytail are drawing something together, and he is still thinking about Megan.] (Right path) [Cueball and Megan are hiking together, and he is still thinking about Ponytail.] (Left path) [Cueball and Ponytail are holding hands looking at each other, and he continues to think of Megan.] (Right path) [Cueball and Megan are holding hands looking at each other, and he continues to think of Ponytail.] [Below the previous two panels two longer arrows again reunite into one central panel.] [Two gravestones are next to each other. One of them (Cueball's) is thinking about a third gravestone (for the girl he did not choose).]

Outreach

Outreach

https://www.xkcd.com/585

https://www.explainxkcd.com/wiki/index.php/585:_Outreach

[Ponytail faces two Cueball-like guys. All three are wearing goggles and lab-coats. Between them on a shelf stands a microscope and a beaker.] Ponytail: The tracking tag will record the shark's movement and habits. [The capsule is shown to float upward towards a water surface.] Ponytail (narrating): Then, it will pop free and float to the surface. [A coast is shown, with arrows directed from water to land. A small white circle on one of the arrows indicate the balloon.] Ponytail (narrating): We can't afford a recovery program, so the capsules will inflate helium balloons, drift over land, [The capsule is shown in close up. It has a caption on it.] Ponytail (narrating): And hopefully be found and mailed to us. Any questions? Caption: If found please call [Ponytail is standing over a groggy shark on a boat, with water behind her and a coastline in the background. She attaches the tracking tag to the shark.] Chunk [The shark is dropped headfirst off the boat, into the water with a large splash.] Sploosh Shark: !!! [The course of the shark is shown, weaving around islands.] [The capsule is shown sticking out of the shark at the moment it is ready to pop free.] Click [The capsule remains attached to the shark.] [The balloon starts to inflate, still attached to the shark and underwater.] Hissss [As the balloon inflates, it starts to pull the shark to the surface.] Shark: ?? [The balloon breaks the surface, pulling the shark with it.] [Science Girl with a black ponytail, eating an ice cream cone is standing together with Cueball to the right in an otherwise empty frame.] [Two screaming scientists (A Cueball-like guy and Ponytail) runs past the two, who turns to look after them. The guy is holding the microscope and Ponytail the beaker from the first frame.] Scientists: Aaaaaaaa [A shark attached to a huge balloon floats past the girl and Cueball, it follows the scientists while snapping it's jaws.] Shark: Chomp chomp [After the shark is gone, Science Girl turns to Cueball.] Science Girl: Daddy? Cueball: Yes? Science Girl: I want to be a scientist.

Scientific animal tracking is commonly used to learn more about other species, particularly endangered ones, as a way of better understanding their physiology, behavior, and what risks they face in the wild. It's used in a wide variety of sciences, including wildlife biology, conservation, wildlife management and zoology. The scientists in this comic are working on a rather limited budget as Ponytail explains, say that they can't afford the (relatively minuscule) cost of hiring someone to retrieve a tracking tag from the water. So they devise a plan that would actually cost far more: create one that will pop free, float to the surface, and inflate a giant helium balloon, causing it to gradually drift over land. Eventually, the balloon will slowly deflate and soft-land, and with any luck someone will find it and mail it back to the scientists. The shark is depicted much larger than the humans, and the quantity of helium necessary to lift it (as the later panels show) would be extremely expensive. It goes horribly, hilariously wrong. The tag can't quite pop free from the shark, and proceeds to inflate the balloon while the shark is still attached . Although the balloon is shown too small to lift the shark (a helium balloon can only lift approximately one gram per liter in air), but the shark miraculously rises right along with the tracker tag, drifts back over land, and goes right after the scientists that had been tracking it. When Science Girl (maybe in her first appearance, before she got her buns) sees the two scientists running frantically from a flying shark, she figures that if such excitement is a daily part of a scientist's job, that's the job for her, as she tells her daddy Cueball . The title of the comic, Outreach , refers to the type of activities that scientists do in order to motivate kids to become scientists when they grow up, and it clearly worked for Science Girl who displays keen interest and great knowledge on many subjects in her next appearances. The title text suggests keeping shark repellent by one's bed to account for the quite-unlikely event of something like this happening. Because you never know. It may be a reference to the Adam West Batman film where Batman just happens to have some in his helicopter. In reality, a balloon meant for lifting a tracker tag would be much too small to lift the shark, which is portrayed as being larger than person, so there is no danger. In addition, since sharks are fish, and fish cannot survive above water, the shark would die even if this could happened in real life. This doesn't stop movies like Sharknado (which was filmed after this comic) to portray sharks floating in the air. The title text of 1910: Sky Spotters seems to be a reference to this comic. [Ponytail faces two Cueball-like guys. All three are wearing goggles and lab-coats. Between them on a shelf stands a microscope and a beaker.] Ponytail: The tracking tag will record the shark's movement and habits. [The capsule is shown to float upward towards a water surface.] Ponytail (narrating): Then, it will pop free and float to the surface. [A coast is shown, with arrows directed from water to land. A small white circle on one of the arrows indicate the balloon.] Ponytail (narrating): We can't afford a recovery program, so the capsules will inflate helium balloons, drift over land, [The capsule is shown in close up. It has a caption on it.] Ponytail (narrating): And hopefully be found and mailed to us. Any questions? Caption: If found please call [Ponytail is standing over a groggy shark on a boat, with water behind her and a coastline in the background. She attaches the tracking tag to the shark.] Chunk [The shark is dropped headfirst off the boat, into the water with a large splash.] Sploosh Shark: !!! [The course of the shark is shown, weaving around islands.] [The capsule is shown sticking out of the shark at the moment it is ready to pop free.] Click [The capsule remains attached to the shark.] [The balloon starts to inflate, still attached to the shark and underwater.] Hissss [As the balloon inflates, it starts to pull the shark to the surface.] Shark: ?? [The balloon breaks the surface, pulling the shark with it.] [Science Girl with a black ponytail, eating an ice cream cone is standing together with Cueball to the right in an otherwise empty frame.] [Two screaming scientists (A Cueball-like guy and Ponytail) runs past the two, who turns to look after them. The guy is holding the microscope and Ponytail the beaker from the first frame.] Scientists: Aaaaaaaa [A shark attached to a huge balloon floats past the girl and Cueball, it follows the scientists while snapping it's jaws.] Shark: Chomp chomp [After the shark is gone, Science Girl turns to Cueball.] Science Girl: Daddy? Cueball: Yes? Science Girl: I want to be a scientist.

Mission to Culture

Mission to Culture

https://www.xkcd.com/586

https://www.explainxkcd.com/wiki/index.php/586:_Mission_to_Culture

[Cueball is pulling Megan by her feet. She is holding onto the carpet, which visibly folds under her tug.] Cueball: We're getting some culture in you if it kills you. Megan: Don't wanna. [Cueball is pushing Megan at the front door, with steps leading down outside. Megan is curled up with both her feet and her hands up on the middle of the door, her back arching out towards Cueball.] Cueball: All you listen to is techno. Megan: But... the symphony? [Cueball and Megan stand in line between two other couples; A guy, who only has hair around his neck and a cane, and Hairbun stands behind them. A guy with a sailor cap and a woman with a big hair stands before them.] Megan: I think we're the only people here under 60. Cueball: Shhh. [The couple sit in the audience just before the concert.] Megan: The right side is definitely better. Cueball: Better? Megan: They've all got bigger instruments. I bet they make more money. Cueball: *Sigh*

Cueball wants to take Megan out for his idea of a cultural experience; a symphony . The inference is that Megan's culturally impoverished because "all she ever listens to is techno ". After much griping on various levels, for instance complaining that all the other attendees are above sixty years old, she starts to get into the experience — sort of. The big 'cultural lesson' she (mis)gleans from the experience is similar to what a sporting aficionado would gain from watching a sports event. So it could be said that Cueball's mission to culture was a mission impossible in Megan's case. Her observation regards the seating configuration of a typical modern orchestra , in which the violinists all sit audience-left, while the violists , cellists and bassists , with clearly larger instruments, are on the right. But it is not the size of an instrument that determines the payroll of a musician. [ citation needed ] The title text is just icing on the cake. A sampler is an instrument frequently used in techno music that samples other sounds and plays them back, usually electronically altered. Remixing is a process, also often used in techno, of editing recorded music to get a different sound. Many classical pieces have had success as techno remixes. One example is Pachelbel's Canon in D major, referred to in the title text of 339: Classic . Techno music is the subject of 411: Techno and is also referenced in 740: The Tell-Tale Beat . Three of the old people in the line look very similar to the old people in 572: Together . In the very next comic 587: Crime Scene a man is again shown with hair only around the side of his head. [Cueball is pulling Megan by her feet. She is holding onto the carpet, which visibly folds under her tug.] Cueball: We're getting some culture in you if it kills you. Megan: Don't wanna. [Cueball is pushing Megan at the front door, with steps leading down outside. Megan is curled up with both her feet and her hands up on the middle of the door, her back arching out towards Cueball.] Cueball: All you listen to is techno. Megan: But... the symphony? [Cueball and Megan stand in line between two other couples; A guy, who only has hair around his neck and a cane, and Hairbun stands behind them. A guy with a sailor cap and a woman with a big hair stands before them.] Megan: I think we're the only people here under 60. Cueball: Shhh. [The couple sit in the audience just before the concert.] Megan: The right side is definitely better. Cueball: Better? Megan: They've all got bigger instruments. I bet they make more money. Cueball: *Sigh*

Crime Scene

Crime Scene

https://www.xkcd.com/587

https://www.explainxkcd.com/wiki/index.php/587:_Crime_Scene

[A crime scene is surrounded by tape wound around several pins four of which are inside this panel. A large black pool is on the ground, with splashes around it, and a hammer lying in one of these splashes. Two people are standing outside the tape; a police officer with a peaked cap with a white emblem is standing closest and to his left is a man with male pattern baldness, who we learn is called George.] Policeman: Looks like a murder-suicide. George: Any interesting mathematical patterns? Policeman: No, George, just two dead bodies and a lot of blood. George: Two... That's the third Fibonacci number! Policeman: Not now, George. [Caption below the frame:] When Mathnet shut down, the officers had trouble reintegrating into the regular L.A.P.D.

Mathnet was a segment on the children's television show "Square One Television", where police mathematicians solved crimes and other mysteries by math. It parodies the Dragnet TV show (and earlier radio drama ) about the Los Angeles Police Department (LAPD). This comic plays on that by implying that Mathnet was a real department of the LAPD, and that when the show was cancelled and the department was shut down its mathematicians were forced to become regular detectives. Here, George Frankly, one of the two lead detectives on the show (a parody of Dragnet character Frank Smith), observes a murder scene along with another officer. His fellow officer, knowing him, tries to tell him off by saying that it is just two dead bodies. As a mathematician, George is constantly looking for potential patterns in the data. However, in this instance there are no obvious mathematical patterns, yet George nonetheless tries to look for one and observes that "two" is the third Fibonacci number . Since several small numbers are in the Fibonacci sequence, the fact that the number of bodies is one of these numbers is not the least interesting. The other officer tries to shut him down, discouraging this unhelpful line of thought. The title text shows that this may not have helped since George now thinks he can see a Mandelbrot set , but he does quickly realizes that it was just blood splatters. The Mandelbrot set is a formula used to create certain kinds of fractals that you might imagine seeing in the something like blood spatters. The last word Golly is in response to George realizing he is seeing blood spatters - something he probably never did before on the children show. The second comic in a row (and third in 16 comics) where a man is drawn with hair only on the sides of his head. [A crime scene is surrounded by tape wound around several pins four of which are inside this panel. A large black pool is on the ground, with splashes around it, and a hammer lying in one of these splashes. Two people are standing outside the tape; a police officer with a peaked cap with a white emblem is standing closest and to his left is a man with male pattern baldness, who we learn is called George.] Policeman: Looks like a murder-suicide. George: Any interesting mathematical patterns? Policeman: No, George, just two dead bodies and a lot of blood. George: Two... That's the third Fibonacci number! Policeman: Not now, George. [Caption below the frame:] When Mathnet shut down, the officers had trouble reintegrating into the regular L.A.P.D.

Pep Rally

Pep Rally

https://www.xkcd.com/588

https://www.explainxkcd.com/wiki/index.php/588:_Pep_Rally

[Ponytail stands in front of crowded bleachers (with only Cueballs in it), waving pompoms high in the air.] Ponytail: Lakeview High is the best! Crowd: Yeah! Voice #1: Wait, why? [Zoom on Ponytail, now with her hands and pompoms down.] Ponytail: What? Voice #1 (off-screen): A guy on the North High football team helped me rebuild my deck. Voice #1 (off-screen): It seems ungrateful to presume we're better. [Same picture with Ponytail now just listening.] Voice #1 (off-screen): I mean, school districts are just based on zip codes. Voice #2 (off-screen): Their principal donated a kidney to my dad. [Ponytail looks down, holding up her pompoms.] Voice #1 (off-screen): I'm texting with my friend there now. He says it's okay, and we're invited to their events if we want. Voice #1 (off-screen): But he sounded kind of hurt. Voice #2 (off-screen): Why are we doing this rally, again?

Any American who went to high school remembers the convocations they had during football or basketball season, in which class would be interrupted and everyone was crowded into the gymnasium for a pep rally . Cheerleaders would cheer, they'd play the school fight song, the cheerleaders might do a routine, and the team would be introduced. This is used to inspire school spirit and get people excited about attending the games so that they'd come to the games and spend money on tickets and concessions. A common boast at pep rallies is "Our school is the best!" "Wait, why?" says one of the students, quite logically. Why is their school the best? The student population is simply made up of students living in the general ZIP code of the school's location. There's no intrinsic reason why any school is any better than the rest of them in any way that really matters in real life. And even having the #1 basketball or football team in the state doesn't mean the students in that school are any "better" than anyone else. This comic subverts the usual expectation of unanimous agreement with the cheerleader's sentiment, and reminds you that people who go to other schools or root for other teams aren't "bad people". In fact, they are capable of being quite kind as is demonstrated by the North High football team who helped rebuild someone's deck, the principal who donated his kidney, and the welcoming invitation from one of the student's friends to his school's events. Randall would no doubt argue that this is the same of people who follow a different religion than you, are of a different ethnicity, or have a different political party affiliation. The title text says that Randall was weirded out by pep rallies growing up, as many introverted people do because of the noise and excitement, and possibly because of the thinking presented in this comic. Now that he's older, he finds them even more creepy, perhaps because of learning about historical events that feel similar like the Nuremberg Rallies or even the various tribalisms of adults. [Ponytail stands in front of crowded bleachers (with only Cueballs in it), waving pompoms high in the air.] Ponytail: Lakeview High is the best! Crowd: Yeah! Voice #1: Wait, why? [Zoom on Ponytail, now with her hands and pompoms down.] Ponytail: What? Voice #1 (off-screen): A guy on the North High football team helped me rebuild my deck. Voice #1 (off-screen): It seems ungrateful to presume we're better. [Same picture with Ponytail now just listening.] Voice #1 (off-screen): I mean, school districts are just based on zip codes. Voice #2 (off-screen): Their principal donated a kidney to my dad. [Ponytail looks down, holding up her pompoms.] Voice #1 (off-screen): I'm texting with my friend there now. He says it's okay, and we're invited to their events if we want. Voice #1 (off-screen): But he sounded kind of hurt. Voice #2 (off-screen): Why are we doing this rally, again?

Designated Drivers

Designated Drivers

https://www.xkcd.com/589

https://www.explainxkcd.com/wiki/index.php/589:_Designated_Drivers

[Cueball is addressing three people outside a bar, indicated by a sign (two Cueball-like guys and Megan).] Cueball: Wait, who's driving? First Cueball-like guy: Why? First Cueball-like guy: Tom, right? [Zoom in on Cueball.] Cueball: Yes, but we have to leave in two groups. One of which will need at least two drivers. [There is text both above and below a flowchart with arrows between a group of the three people Cueball is talking to, and three houses that are labeled 'bar', 'dinner', and 'party'. Three lines point from the group of people to the bar and a fourth arrives from the party. Four lines points away from the bar. Two goes to the dinner one to the party and one away to the left. There are six arrows arriving at the dinner. Apart from the two lines coming from the bar, there is one long arrow pointing to the dinner from the left and two coming in from above. One more comes from the party below. Six arrows points away. One arrow goes away to the top right, the other five arrows points straight down to the party. There are also six arrows coming and leaving the party. Apart from the five from the dinner there was the one coming in from the bar. The six arrows leaving are the one arrow that went to the bar and the one to the dinner. The other four leaves in two groups of two, on straight down and two curving to the left.] Cueball (off-panel): Someone has to get Paul, and Julia and Emily have to leave by 10:00. Labels: Bar Labels: Dinner Labels: Party Cueball (off-panel): The logistics of who can get drunk are nontrivial. [The second Cueball-like guy to the right has an goat on a string behind him, which was not visible in the first panel, as he was at that time only partly inside the frame.] Second Cueball-like guy: Yeah, and I can't ride in a car with the wolf because he'll eat my goat. Cueball: Dammit, guys.

When a group of people go together to any kind of event where they expect to drink alcohol, and would like to drive to and from the event, it is usual to select one who has to be the designated driver . [ citation needed ] This person will then stay sober during the event, and can thus safely drive the other people home afterwards disregarding how drunk the other people become. However, as this comic points out, if it's not a simple task of going from A to B and back, all together at the same time, then it becomes a complex problem that requires an intricate kind of strategy and logical thinking to solve. And may need more than one driver. In this comic Cueball addresses his friends, regarding this problem right before they enter a bar. It seems they have already decided that one of the friends will be the designated driver. But then Cueball mentions that they will have to leave in two groups. And for some reason one of these groups will need at least two drivers (this is hard to explain - see below under number of drivers .) So now they already need three designated drivers. Furthermore, someone has to go and pick up another friend. And also two of them have to leave earlier than the rest by 10:00. In the third panel the situation seems to be illustrated. Three people are drawn outside the bar with three lines going to the bar, so the number of lines leaving and entering each destination seems to represent a person each. Since the number of people leaving and entering each destination is the same, this makes it seem like the diagram is intended to be accurate. There are four people entering and exiting the bar and six people entering and exiting both the party and the dinner. The confusing part of the diagram is that there are only three people at the bar to begin with, not the four shown in the first panel. It also seems strange that someone will go back to the bar and especially that another goes back to the dinner from the party. It is thus not easy to make the diagram fit the description. See below for a possible take on the chart . But the general concept would be that some people meet at a bar before joining the rest of a group at dinner, then later most of these move on to a party. After the party (or bar/dinner) people are going to head home in different groups. The enormous complexities of planning who car pools with whom, from where to where, and when, make an excellent logic puzzle. And what is worse, anyone who has to drive needs to stay sober. So it is important to solve the puzzle before the drinking starts, or else there will be too few that can drive, or too many who never get to drink. To make matters worse Tom complicates this already complicated logical puzzle , by involving the classic logic puzzle of the wolf, goat and cabbage (sometimes also known as Fox-chicken-grain puzzle ). In the last panel, the guy is shown standing with a goat on a tether, saying he can't be in the car with the wolf. Cueball is then brought to swearing over this. (The goat puzzle was also the subject of 1134: Logic Boat and 2348: Boat Puzzle ). And this may go some way of explaining why there needs to be a number of drivers . The title text makes it clear why ordering a taxi is out of the question as it would take money out of the beer budget. Of course it also cost money to use your own car for gas etc. But when you already have a car, it is always cheaper to use that than pay for a taxi. It's possible to match the chart up with the events in the comic if we assume two things: first, that everyone's initial position in the chart is at home, and second, that the party takes place at Cueball's house. Whether or not Randall intended it this way isn't certain. For clarity, I'll be referring to the first cueball as Cueball, the second as David, Megan as Emily, and the third cueball as Tom. Unless a more efficient solution exists, the minimum number of people that have to remain sober is three: Tom, David, and either Julia or Emily. Emily is able to begin drinking the earliest, starting at the bar and continuing the rest of the night. If the place everyone is having dinner at serves alcohol, Paul can begin drinking at dinner. If Emily elected to stay sober, Julia can start drinking when Paul does. Cueball is the last to be able to drink, only getting to start once everyone is at the party. Interestingly enough, if the goat and wolf cannot drive, then they only make a difference if Paul has the wolf, in which case David would have to pick Paul up and take him home, and Tom and his goat would leave after dinner. If either the wolf or the goat can drive, then a sober human driver is not needed for the vehicle in which that animal travels. [Cueball is addressing three people outside a bar, indicated by a sign (two Cueball-like guys and Megan).] Cueball: Wait, who's driving? First Cueball-like guy: Why? First Cueball-like guy: Tom, right? [Zoom in on Cueball.] Cueball: Yes, but we have to leave in two groups. One of which will need at least two drivers. [There is text both above and below a flowchart with arrows between a group of the three people Cueball is talking to, and three houses that are labeled 'bar', 'dinner', and 'party'. Three lines point from the group of people to the bar and a fourth arrives from the party. Four lines points away from the bar. Two goes to the dinner one to the party and one away to the left. There are six arrows arriving at the dinner. Apart from the two lines coming from the bar, there is one long arrow pointing to the dinner from the left and two coming in from above. One more comes from the party below. Six arrows points away. One arrow goes away to the top right, the other five arrows points straight down to the party. There are also six arrows coming and leaving the party. Apart from the five from the dinner there was the one coming in from the bar. The six arrows leaving are the one arrow that went to the bar and the one to the dinner. The other four leaves in two groups of two, on straight down and two curving to the left.] Cueball (off-panel): Someone has to get Paul, and Julia and Emily have to leave by 10:00. Labels: Bar Labels: Dinner Labels: Party Cueball (off-panel): The logistics of who can get drunk are nontrivial. [The second Cueball-like guy to the right has an goat on a string behind him, which was not visible in the first panel, as he was at that time only partly inside the frame.] Second Cueball-like guy: Yeah, and I can't ride in a car with the wolf because he'll eat my goat. Cueball: Dammit, guys.

Papyrus

Papyrus

https://www.xkcd.com/590

https://www.explainxkcd.com/wiki/index.php/590:_Papyrus

[Caption above the panel:] My Hobby: Getting typography geeks heartfelt cards printed in "Papyrus" and watching them struggle to act grateful. [Ponytail is holding a card, with lines of indiscernible text, open and looking down, specifically neither on the card nor on Cueball, who is watching her instead. An angry tic is flicking on her forehead.] Ponytail: Thank you for the *twitch* ... lovely... *twitch* birthday card!

One of the comics in the " My Hobby " series, this one touches on the fact that Papyrus (the font) is considered to be overused by many typography geeks, including the font's own creator. Pretending that he doesn't know that, Cueball gives Ponytail a heartfelt card written in that font just to see her twitch. The title text says that Randall actually likes Papyrus, even if it is overused, and refers to the fact that he will soon be receiving hate-mail from people who dislike Papyrus. Those mails will be written in Helvetica , another commonly-used sans-serif font that is highly esteemed by typography geeks, designers, and often hipsters. It suggests that the designers would also take the time to check the " kerning ", editing the spacing between individual letters to be visually pleasing - a time-consuming activity that, it can be suggested, would only be noticed by other designers. See also 1015: Kerning . [Caption above the panel:] My Hobby: Getting typography geeks heartfelt cards printed in "Papyrus" and watching them struggle to act grateful. [Ponytail is holding a card, with lines of indiscernible text, open and looking down, specifically neither on the card nor on Cueball, who is watching her instead. An angry tic is flicking on her forehead.] Ponytail: Thank you for the *twitch* ... lovely... *twitch* birthday card!

Troll Slayer

Troll Slayer

https://www.xkcd.com/591

https://www.explainxkcd.com/wiki/index.php/591:_Troll_Slayer

[A list of post comments alongside pictures on a website. The first picture shows a page from a book/website with a small black picture with a white feature in the upper left corner and text to the right and below it. The second picture shows Cueball in front of three people, with a unclear drawing to the right (is it a canon?). The third picture shows a man with a black hat holding up a sword to the left and a trumpet to the right. The fourth and last picture is cut off in the middle at the bottom of the frame. The visible top part shows a drawing of a mans face from the nose/ears and up. The man has black hair and says LOL]. Text picture: Hey, let's troll the fuck out of the Twilight boards Cueball picture: I'm in. Should be fun Man with sword picture: Me too. Signing on now. LOL face picture: Lol angsty teens. [Stephenie Meyer is shown sitting facing right and chatting at her computer. She get's a reply from the screen. It looks like she actually speaks the lines of text to someone, but she only types it in via the keyboard. This becomes clear in in the next panel where the pimpled boy she talks to obviously types his reply on the keyboard. Across the top border of the frame is a smaller frame with a caption:] Hours Later: Stephenie Meyer (typing): Hi, it's Stephenie Meyer. Fine, you don't like my books. But please leave us alone. Pimpled boy (from computer): Show us your tits. Stephenie Meyer (typing): I asked politely. Don't make me get tough. [A boy with lots of pimples and black hair is sitting at his computer typing (facing the other way towards Stephenie in the previous panel). He writes his reply on the keyboard and receives a reply from Stephenie coming out of the computer.] Pimpled boy (typing): And what, call the internet police? You don't get it, do you? We've been trolling for years. We're all anonymous. There's nothing you can do to hurt us. We're the net's hate machine. Stephenie Meyer (from computer): Okay. Just remember, I gave you a chance. *Disconnected* . [A page from a book is shown lying slanted across the panel. Some of the text is thus cut off at the edges of the frame. The first eight lines can be read clearly, even though the last letter in both the 2nd and sixth line is partly cut-off. Below that there are four incomplete lines, where only the visible part will be transcribed, but a good guess at the missing text is written in square brackets. Across the top border of the frame is a smaller frame with a caption:] Six Months Later: Vampires! Book VI Edward ran a pale hand through his perfect golden- bronze hair, then signed on to 4chan.org, the darkest place on the internet, where all his vampire compatriots spent their time. Suddenly, there was [a] [sha]rp knock at the d[oor] [?] swept in [?] [?r?]ing [?] [Another list of post comments alongside pictures on the same website as in the first panel. The first picture shows a man with black hair and a woman with long hair standing with their backs against each other (probably Edward and Bella from the books). The second picture is just a white frame with the text Dawnz. The third picture shows a person from the chest and up. The person has black hair and black clothes, with some kind of collar. The fourth and last picture shows two chess piece a large one in front of the other. The picture is shown completely but the text message seems to be more than two lines long, but only the top two lines are shown. Across the top border of the frame is a smaller frame with a caption:] Shortly thereafter: Two people picture: OMG I love this place it's so edgy being anonymous Dawnz picture: Whos your favorite vampire Collared person picture: Check out my pic Im so dark just like this site Chess piece picture: Any Twilight fans in Dallas want to meet a lonely [Back to the boy with lots of pimples now sitting resigned at his computer without typing.] Hairy: Oh... Oh God.

Stephenie Meyer is the author of the Twilight novels , a series of vampire novels popular with young teens. It is a love it or hate it type of novel, with a large following and a large portion of haters as well. In the comic, 4chan , an imageboard , is featured. Imageboards such as 4chan have the feature to post anonymously. The users of 4chan launch an attack on a Twilight board and Stephenie Meyer asks them to stop. When they refuse, Meyer writes 4chan into her next novel, thereby drawing in a large number of fans of her novel as a counter-attack to what 4chan ran on the Twilight forum. This results in what the original 4chan users consider a ruined imageboard. The title of the comic is drawn from the internet slang term troll , which refers to actively attempting to get a rise out of a forum. In this instance, 4chan attempted to troll a Twilight board and Meyer acted against the troll, making her a "slayer" of them. Obviously the pimpled boy she chats with is very dismayed by this result, as there are now so many more vampire-book-fans than computer geeks on 4chan, and they cannot get through with any of their funny/evil plans anymore. There may also be a reference to the famous vampire slayer known as Buffy , seeing that Stephenie's main character vampires do not need to be slain, but she then turns on those who tries to do so in real life on the message board. The pictures used on the two panels showing the 4chan imageboard tells a lot about their users. It is unclear what the text page refers to. And also what it is that Cueball is standing next to. But a black hat, as shown in the third picture is typical for an internet troll (see the xkcd version of Black Hat ), and also the guy saying LOL is already laughing out loud at you before you read his text. He also LOL's in his comment about the angsty teens that reads the books, and whom he looks forward to trolling. In the second 4chan panel all four images relate to Twilight . The first picture most likely depicts Edward Cullen and Bella Swan (from the movies) standing with their backs against each other. This person enjoys being anonymous. The second picture with the text Dawnz refers, in "plural" form, to the last book Breaking Dawn which was split into two films part 1 and part 2 . This person wish to know about peoples favorite vampire, exactly the kind of questions the trolls would have mocked on the Twilight board, now infesting their own site. The third picture is of a person who has tried to dress up like a goth vampire, even commenting on the darkness of the picture. The last picture depicts the cover of the last book Breaking Dawn with the two chess pieces. This fan seems to be searching for a date around Dallas... The title text refers to Walt Kelly 's famous saying . Kelly used it to refer to all of mankind, whereas here it refers to the users of 4chan, by bringing on the enemy of their forum themselves. [A list of post comments alongside pictures on a website. The first picture shows a page from a book/website with a small black picture with a white feature in the upper left corner and text to the right and below it. The second picture shows Cueball in front of three people, with a unclear drawing to the right (is it a canon?). The third picture shows a man with a black hat holding up a sword to the left and a trumpet to the right. The fourth and last picture is cut off in the middle at the bottom of the frame. The visible top part shows a drawing of a mans face from the nose/ears and up. The man has black hair and says LOL]. Text picture: Hey, let's troll the fuck out of the Twilight boards Cueball picture: I'm in. Should be fun Man with sword picture: Me too. Signing on now. LOL face picture: Lol angsty teens. [Stephenie Meyer is shown sitting facing right and chatting at her computer. She get's a reply from the screen. It looks like she actually speaks the lines of text to someone, but she only types it in via the keyboard. This becomes clear in in the next panel where the pimpled boy she talks to obviously types his reply on the keyboard. Across the top border of the frame is a smaller frame with a caption:] Hours Later: Stephenie Meyer (typing): Hi, it's Stephenie Meyer. Fine, you don't like my books. But please leave us alone. Pimpled boy (from computer): Show us your tits. Stephenie Meyer (typing): I asked politely. Don't make me get tough. [A boy with lots of pimples and black hair is sitting at his computer typing (facing the other way towards Stephenie in the previous panel). He writes his reply on the keyboard and receives a reply from Stephenie coming out of the computer.] Pimpled boy (typing): And what, call the internet police? You don't get it, do you? We've been trolling for years. We're all anonymous. There's nothing you can do to hurt us. We're the net's hate machine. Stephenie Meyer (from computer): Okay. Just remember, I gave you a chance. *Disconnected* . [A page from a book is shown lying slanted across the panel. Some of the text is thus cut off at the edges of the frame. The first eight lines can be read clearly, even though the last letter in both the 2nd and sixth line is partly cut-off. Below that there are four incomplete lines, where only the visible part will be transcribed, but a good guess at the missing text is written in square brackets. Across the top border of the frame is a smaller frame with a caption:] Six Months Later: Vampires! Book VI Edward ran a pale hand through his perfect golden- bronze hair, then signed on to 4chan.org, the darkest place on the internet, where all his vampire compatriots spent their time. Suddenly, there was [a] [sha]rp knock at the d[oor] [?] swept in [?] [?r?]ing [?] [Another list of post comments alongside pictures on the same website as in the first panel. The first picture shows a man with black hair and a woman with long hair standing with their backs against each other (probably Edward and Bella from the books). The second picture is just a white frame with the text Dawnz. The third picture shows a person from the chest and up. The person has black hair and black clothes, with some kind of collar. The fourth and last picture shows two chess piece a large one in front of the other. The picture is shown completely but the text message seems to be more than two lines long, but only the top two lines are shown. Across the top border of the frame is a smaller frame with a caption:] Shortly thereafter: Two people picture: OMG I love this place it's so edgy being anonymous Dawnz picture: Whos your favorite vampire Collared person picture: Check out my pic Im so dark just like this site Chess piece picture: Any Twilight fans in Dallas want to meet a lonely [Back to the boy with lots of pimples now sitting resigned at his computer without typing.] Hairy: Oh... Oh God.

Drama

Drama

https://www.xkcd.com/592

https://www.explainxkcd.com/wiki/index.php/592:_Drama

[Megan and two Cueball like guys are sitting together.] Megan: Man, sex has all these crazy social rules. They just create drama. Cueball: Let's agree to change them, and make sex simple! Friend: Okay! [Cueball gets up and goes out the door.] Cueball: Hooray! We've solved the problem of drama! Cueball: I'll go tell everyone! [There is a graph labeled drama. Below is an axis and below that an arrow marked with time. A vertical dotted line is labeled and indicates the rule change. Drama is low, although fluctuating, before the rule change, then sharply increases afterward and continues to increase.] Drama Time Rule change [Cueball closes the door and then leans against it.] Cueball: Holy shit Cueball: Guys Cueball: People are complicated!

Megan and two Cueball -like guys discuss how irrational society's interactions about sex are. They decide to throw out all these silly societal rules to end drama forever and spread this philosophy to everyone they know, which immediately leads to a huge increase in drama as shown in the chart. As one of the Cueballs in the comic states, people are indeed complicated and—crucially—what seems intuitive and rational to one person might seem completely irrational to someone else; so throwing out all the rules one person thinks make no sense isn't going to mean the world suddenly makes sense for everyone else. Instead, everyone who understands the old rules, whether they like them or not, will suddenly find themselves in a completely alien world to which they have no idea how to relate. Furthermore, any one person's sense of what seems rational is based on incomplete information . The three people are trying to change all the sex rules—like the engineers referenced in the title text who think they can "solve" the stock market—can't even begin to conceive of all the chaotic factors affecting the system they're trying to fix, so they have no way of knowing which rules are truly rational and which aren't. Geeks often fall prey to the fallacy that human interactions can be easily simplified if only a group of sufficiently qualified geeks put their minds to it as laid out in The Geek Social Fallacies and The Geek Social Fallacies of Sex . Social rules that are adopted partly to avoid drama include laws surrounding marriage and alimony . These rules differ a large amount, but not incomparably, across different cultures. The study of them is a major concern in social science, and it is not unheard of to conjecture new ones, for example the work of the evolutionary psychologist Diana Fleischmann . The situation in the title text, with a bunch of engineers diving into the stock market, is also mentioned in 1570: Engineer Syllogism . [Megan and two Cueball like guys are sitting together.] Megan: Man, sex has all these crazy social rules. They just create drama. Cueball: Let's agree to change them, and make sex simple! Friend: Okay! [Cueball gets up and goes out the door.] Cueball: Hooray! We've solved the problem of drama! Cueball: I'll go tell everyone! [There is a graph labeled drama. Below is an axis and below that an arrow marked with time. A vertical dotted line is labeled and indicates the rule change. Drama is low, although fluctuating, before the rule change, then sharply increases afterward and continues to increase.] Drama Time Rule change [Cueball closes the door and then leans against it.] Cueball: Holy shit Cueball: Guys Cueball: People are complicated!

Voynich Manuscript

Voynich Manuscript

https://www.xkcd.com/593

https://www.explainxkcd.com/wiki/index.php/593:_Voynich_Manuscript

[Weird root vegetables surround a strange script.] [Megan holding up book to Cueball.] Megan: This is the Voynich manuscript— a book, allegedly 500 years old, written in an unrecognized script. It's some kind of visual encyclopedia of imaginary plants and undeciphered "recipes". [Megan points while Cueball opens the book.] Megan: It could be a hoax, a lost language, a cipher, an alien text, glossolatia — no one knows. Cueball: No one? But it's obvious. [Megan continues to talk. Cueball holds the now closed book.] Megan: ... Obvious? Linguists and cryptographers have been stumped for decades. Cueball: They forget. Human nature doesn't change. [Close up of Megan and Cueball - the book is off panel.] Cueball: Just imagine someone found a book from our time, full of lists, illustrations, tables, and long, dry descriptions of nonexistent worlds written in an invented language. What have they found? Megan: ...Dear Lord. It is obvious. [Three people are standing around pawns and a die. One is holding a sheet of paper, another is holding a book, the third is holding a scythe. At the top of the panel there is a frame with the following text:] 500 Years Earlier: Person #1: Forsooth! I concoct an elixer of courage. Person #2: Nae! The source booke sayeth that requires some wolfsbane! Person #3: Your druid doth lose two points.

The Voynich manuscript is a very detailed book written in an unknown script, describing plants and recipes, most of which lack a real-world analogue. Over the past few decades, linguists and cryptographers have unsuccessfully attempted to decode the book. A cut out from the book is depicted in the first frame (real or similar). Tabletop role-playing games (such as Dungeons and Dragons ) are fantasy games with extremely detailed descriptions of fantastical worlds. The invented language is probably a reference to The Lord of the Rings in which author J. R. R. Tolkien invented several languages of which Sindarin (Grey elvish), and Quenya (High elvish), are the most famous. After being shown the manuscript for the first time by Megan , Cueball argues that it should be obvious that it's just an ancient role-playing-game rulebook, since the human tendency to invent fantastical worlds must have also existed in the past. That it is this obvious was again stated when the manuscript was referenced in 1501: Mysteries . In the last panel the book is used, 500 years ago, to play a game similar to Dungeons and Dragons. They speak in a somewhat outdated English. The reference to the real plant Wolfsbane could also be a reference to another invented world, as it is memorably mentioned in the first book of the Harry Potter series. After concluding this, a shocked Cueball then asks in the title text how Megan got her hands on the original manuscript, which is in the Yale University's Beinecke Rare Book and Manuscript Library . Rigorous security rules now only allow carefully controlled access to materials under video surveillance, thus Cueball's reaction upon realizing Megan has somehow gotten her hands on the original manuscript. He then unexpectedly goes on to suggest the prosaic activity of playing Druids and Dicotyledons , assuming such a game could be defined by the manuscript. [Weird root vegetables surround a strange script.] [Megan holding up book to Cueball.] Megan: This is the Voynich manuscript— a book, allegedly 500 years old, written in an unrecognized script. It's some kind of visual encyclopedia of imaginary plants and undeciphered "recipes". [Megan points while Cueball opens the book.] Megan: It could be a hoax, a lost language, a cipher, an alien text, glossolatia — no one knows. Cueball: No one? But it's obvious. [Megan continues to talk. Cueball holds the now closed book.] Megan: ... Obvious? Linguists and cryptographers have been stumped for decades. Cueball: They forget. Human nature doesn't change. [Close up of Megan and Cueball - the book is off panel.] Cueball: Just imagine someone found a book from our time, full of lists, illustrations, tables, and long, dry descriptions of nonexistent worlds written in an invented language. What have they found? Megan: ...Dear Lord. It is obvious. [Three people are standing around pawns and a die. One is holding a sheet of paper, another is holding a book, the third is holding a scythe. At the top of the panel there is a frame with the following text:] 500 Years Earlier: Person #1: Forsooth! I concoct an elixer of courage. Person #2: Nae! The source booke sayeth that requires some wolfsbane! Person #3: Your druid doth lose two points.

Period

Period

https://www.xkcd.com/594

https://www.explainxkcd.com/wiki/index.php/594:_Period

[Cueball is standing with a hand to his chin looking towards a woman off-panel right. In all panels the woman answers off-panel with a small starburst close to the right panels border indicating from where her speak emanates.] Woman's voice (off-panel): Ugh. Stupid uterus. Cueball: Hey, your period is every 28 days, right? [Cueball is standing hands down.] Woman's voice (off-panel): Yes, why? Cueball: Well, period = T = 1/f. Woman's voice (off-panel): So? [Cueball holds up a finger in front of him.] Cueball: Using this, we can calculate something you already know. Woman's voice (off-panel): What? [Cueball is standing hands down.] Cueball: Your uterus-hertz. Woman's voice (off-panel): If I could get up I'd smack you.

A period, also called a menstrual cycle , is a process marked by (among other things) a few days of abdominal cramps occurring roughly once a month for women in the reproductive age . "Period" ( T ) is also the term in mathematics for a measure of the rate at which something happens. It measures the length of time between occurrences. For example, a full moon happens about once every 29.5 days, so its period is 29.5 days. By taking the inverse of this, we can get a different measurement, its frequency ( f ) - the number of times an event happens within a given length of time. This is usually measured in hertz (pronounced the same as "hurts"), which is the number of times something happens in a second. Hertz is abbreviated as Hz, and since f = 1/T, with T measured in seconds (s), it follows that 1 Hz = 1 s −1 . The woman has her period every 28 days. Since we can calculate the frequency based on the period, we can, indeed, calculate her "uterus-hertz" but she already knew that her "uterus hurts". Yes, this has all been a setup to a terrible pun to make your head hertz. And if she had not been in such terrible pains that she cannot even get up, she would have smacked Cueball for it, which would really hertz. This makes it even more hertzfull by Cueball, to make fun of his girlfriend in such a state. The woman off screen is probably Megan given that she is most often depicted as Cueball's girlfriend, and the fact that he is in her home with her on the couch is a good indicator that they are intimate. (This is not enough to include this comic as one with Megan). The title text gives the other answer that can be calculated from Cueballs musings, the actual frequency of the womans period which have a period T = 28 days. 413 nanohertz is the correct frequency as shown here by Google Calculator. It can also easily be shown here: f = 1/28 days = 1/(28 days × 24 hours/day × 60 minutes/hour × 60 seconds/minute) = 1/(2,419,200 s) = 4.1336 × 10 −7 s −1 = 413 × 10 −9 Hz = 413 nHz . [Cueball is standing with a hand to his chin looking towards a woman off-panel right. In all panels the woman answers off-panel with a small starburst close to the right panels border indicating from where her speak emanates.] Woman's voice (off-panel): Ugh. Stupid uterus. Cueball: Hey, your period is every 28 days, right? [Cueball is standing hands down.] Woman's voice (off-panel): Yes, why? Cueball: Well, period = T = 1/f. Woman's voice (off-panel): So? [Cueball holds up a finger in front of him.] Cueball: Using this, we can calculate something you already know. Woman's voice (off-panel): What? [Cueball is standing hands down.] Cueball: Your uterus-hertz. Woman's voice (off-panel): If I could get up I'd smack you.

Android Girlfriend

Android Girlfriend

https://www.xkcd.com/595

https://www.explainxkcd.com/wiki/index.php/595:_Android_Girlfriend

[Cueball, holding his hand on Megan's shoulder, talks to his Cueball-like friend, who is holding a drink glass with a cherry.] Cueball: Check out my new android girlfriend. Friend: Is she a sex bot? [The android grabs the cherry out of the friend's drink glass.] Grab [Zoom in on the cherry as the stem is ripped off.] Plink [Zoom to the android, who puts the stem into its mouth.] Nom [The panel is dark gray, except around the android's mouth, where there is a bright flash and then a brighter cross going out from there. Both Cueball and his friend hold up their hands to protect their eyes.] Kzzzzt [The android takes a step away from Cueball and reaches toward the friend's crotch. The friend holds up his hand protectively in front of him.] Friend: I don't think arc-welding a cherry stem counts as sexy. Android: Remove your pants. Friend: No.

This is the first (of two) comics in the Android series , which continued directly less than two weeks later in 600: Android Boyfriend . Cueball shows off his new "android girlfriend" ( Megan ) to his Cueball-like friend, who asks if the android is a sex bot . The android responds by pulling a cherry stem from the friend's drink and inserting it into her mouth. So far, the action appears to be an emulation of the party trick where someone puts a cherry stem into their mouth and ties it into a knot in order to suggest tongue dexterity that could be put to good use in kissing and oral sex . However, instead of tying the cherry stem in a knot, the android activates an arc welder built into her mouth, which presumably reduces the stem to ashes. The friend proclaims that that trick is definitely not sexy. But then the android aggressively approaches him, reaching out and saying, "Remove your pants". The friend, not eager to experience close genital contact with the arc welder, sensibly, refuses. (Of course he may also not wish to take of his pants in front of his friend, at a party with drinks and presumably other people; or perhaps he does not wish to admit that he actually does find the arc welding act sexy...) The title text bounces a few implications around. Developing robots with the capacity to either learn or feel emotions is an ethical factor and practical consideration that is commonly explored in science fiction . Here, it's proposed that robots programmed for sex would have their emotions set to enjoy sex by default, but then use their capacity to learn to develop preferences on what kind of sex they want to have. This is potentially a psychological issue, mainly as to whether or not it would be considered "unhealthy", but more directly it's a customer satisfaction problem: what if a sexbot were to develop sexual fetishes that its owner finds unappealing? It is also possible that the android shows a level of awareness superior to what is implied by the discussion in the strip. Then using an arc-wielder on that stem could be interpreted as a menace in response to a comment that would be unsensitive if referred to a real person. [Cueball, holding his hand on Megan's shoulder, talks to his Cueball-like friend, who is holding a drink glass with a cherry.] Cueball: Check out my new android girlfriend. Friend: Is she a sex bot? [The android grabs the cherry out of the friend's drink glass.] Grab [Zoom in on the cherry as the stem is ripped off.] Plink [Zoom to the android, who puts the stem into its mouth.] Nom [The panel is dark gray, except around the android's mouth, where there is a bright flash and then a brighter cross going out from there. Both Cueball and his friend hold up their hands to protect their eyes.] Kzzzzt [The android takes a step away from Cueball and reaches toward the friend's crotch. The friend holds up his hand protectively in front of him.] Friend: I don't think arc-welding a cherry stem counts as sexy. Android: Remove your pants. Friend: No.

Latitude

Latitude

https://www.xkcd.com/596

https://www.explainxkcd.com/wiki/index.php/596:_Latitude

[Black Hat is holding a phone up to Cueball.] Black Hat: We're in a narrow window in which people are using Google Latitude, but haven't learned the habit of turning it off when they're doing something discreetly. Black Hat: I wrote an app to log friends' locations and work out addresses and business names. [A timetable is visible. The first column gives the time and splits the day in the half hour intervals starting at 11:00 AM, except for the last entry at 4:10 PM, where the time only jumps 10 minutes. The next two columns represents two persons activities during this time period. In the second column the last letter shown in the comic is partly cut off more or less. This last partly shown letter is written in the transcript, but no guess is made here. See the explanation. Above the table, over the two names, there is a caption:] Locations Time Megan Robert 11:00 AM Home 12:30 PM Eastview Adult Toy Store Home 1:30 PM Home 2:00 PM Laketown Sex Toy Shop School 2:30 PM Home 3:00 PM Fry's Electronics 3:30 PM Ed's Power Tool Emporium Subway 4:00 PM Home 4:10 PM Hospital Burn Ward

Black Hat shows his friend (presumably Robert [aka Rob from the chart]), that he has made a mobile phone application to log and find addresses and business names for the locations of his "friends" using data from Google Latitude which was a location-aware feature of Google Maps that allowed a mobile phone user to allow certain people to view their current location. The reason it is worth doing so for him, is that most of those that use Google Latitude, haven't learned the habit to turn it off when engaging in "discreet" activities. And then Black Hat can access their whereabout which he then uses in his app. The second panel shows the screen of Black Hat's smartphone with the logs for his two friend in table form showing activity for Megan and Robert (Rob), the latter log is partially cut off. (Regarding the use of these names see the trivia section ). Robert's log is fairly innocuous: home at 12:30 PM, school at 2:00 PM, and riding a subway (or possibly in a Subway restaurant ) at 3:30 PM. This log shows that Robert did nothing interesting for Black Hat. There are also several holes in the table compared to the other column. This could either indicate that he stayed this long time those three places, but it could also indicate that Robert has already learned to switch off Latitude when he is not actively using it. This would fit with Black Hat's comment about a narrow window in which people haven't learned this. His friend Robert (the Rob version of Cueball shown here, see the trivia section ), may already have thought of this himself, or maybe Black Hat has mentioned it to him before getting the idea for the app thus warning him about the problem (without meaning to). The reason Black Hat states that there only is a narrow window of time that people forget to turn Google Latitude off , is because people like him will make other people, who forget this, miserable. And then everyone will soon learn to turn the feature off making Black Hat's app useless. Megan's log appears to prove Black Hat's point: She was home at 11:00 AM, at a sex toy store at 12:30 PM, home again at 1:30 PM, at another sex toy store at 2:00 PM, home again at 2:30 PM, then at Fry's Electronics at 3:00 PM, and at a power tool store at 3:30 PM, finally home again at 4:00 PM only to be at the hospital burn ward at 4:10 PM. The last entry is the only one where the interval is not half an hour indicating how fast Megan had to get to the hospital after getting home with her new power tools and electronics. This suggests that Megan first tried the sex toy(s) from the first store, found them insufficiently satisfying, purchased additional sex toys from another store, was still unsatisfied, and then purchased some electronic devices and power tools (either to improve the performance of her sex toys or to apply directly for additional stimulation). The results were apparently more painful than pleasurable, necessitating a quick visit to the hospital burn ward. Overall, Megan has had an at first unsatisfying day and then finally a rather bad day, considering where the burn is most likely to be... She would almost certainly not be pleased to learn that Black Hat has been tracking her whereabouts and sharing this with their mutual friend Rob. The title text shows that Randall liked the T-Mobile G1, also known as the HTC Dream , especially with the upgrade to Android Cupcake , more than he previously thought because it allows for more capabilities and the interface is clean and easy-to-use when compared to other "smartphones" of that time period (because the G1 was the first phone to introduce the Android operating system ) and it allows for special Google networking, allowing for apps like Maps to run better (making it easier to run apps like Latitude). From what able to be gathered in the comic, it is Black Hat who says this, because he is the one who uses the app and shows it off. He would be the most likely one to benefit from this kind of phone running this kind of OS/app. [Black Hat is holding a phone up to Cueball.] Black Hat: We're in a narrow window in which people are using Google Latitude, but haven't learned the habit of turning it off when they're doing something discreetly. Black Hat: I wrote an app to log friends' locations and work out addresses and business names. [A timetable is visible. The first column gives the time and splits the day in the half hour intervals starting at 11:00 AM, except for the last entry at 4:10 PM, where the time only jumps 10 minutes. The next two columns represents two persons activities during this time period. In the second column the last letter shown in the comic is partly cut off more or less. This last partly shown letter is written in the transcript, but no guess is made here. See the explanation. Above the table, over the two names, there is a caption:] Locations Time Megan Robert 11:00 AM Home 12:30 PM Eastview Adult Toy Store Home 1:30 PM Home 2:00 PM Laketown Sex Toy Shop School 2:30 PM Home 3:00 PM Fry's Electronics 3:30 PM Ed's Power Tool Emporium Subway 4:00 PM Home 4:10 PM Hospital Burn Ward

Addiction

Addiction

https://www.xkcd.com/597

https://www.explainxkcd.com/wiki/index.php/597:_Addiction

[Close up of Cueball typing at his computer. Megan's text message to him can be seen coming from the screen with a zigzag line, and Cueball writes a response as seen from the line going from his hand on the keyboard up to his message.] Megan (through the computer): Constant novelty saps my initiative. I'm gonna try to spend a weekend at home without internet. Cueball (writing): I give you an hour. [Megan is standing up, she turns off the computer in front of her by clicking on a button on the screen. Her office chair has rolled back behind her.] Click [Megan stands in front of the computer arms in her sides. Beat panel.] [Zoom out with Cueball sitting in his office chair typing a reply on his computer to the message from Megan as in the first panel.] Megan (through the computer): So far, it's not actually too bad! Cueball (writing): Ahem? Megan (through the computer): Wait. Shit.

Megan is attempting to stay a weekend at home without the Internet as she feels the constant exposure to novelty (from her internet surfing ) saps her own initiative. She writes a "last" on-line message about her resolution to Cueball , but he writes back that he doubts she can do it for even one hour. She turns off her computer (or at least the screen) and stands up triumphantly next to it, however then she logs right back on to write to Cueball that it's not half bad being off-line, thus violating her original attempt as she clearly used the internet to send the message to Cueball. She doesn't even realize she did this until Cueball replies with the written sound Ahem? proving he was right about less than one hour. Very typical of people having some kind of addiction , in this case for being on-line, they may not even realize when they indulge into it, which is the case with Megan here. The title text elaborates on Megan's addiction, saying that when she turns off all of the machines in the room, it results in an "empty-room hum". This is a high pitched buzzing noise, which it is suggested results from the brain increasing its sensitivity to noises. This is a fairly normal experience, but the " whispers " mentioned may be slightly more sinister, as this is frequently associated as a sign of schizophrenia . See also 1590: The Source . [Close up of Cueball typing at his computer. Megan's text message to him can be seen coming from the screen with a zigzag line, and Cueball writes a response as seen from the line going from his hand on the keyboard up to his message.] Megan (through the computer): Constant novelty saps my initiative. I'm gonna try to spend a weekend at home without internet. Cueball (writing): I give you an hour. [Megan is standing up, she turns off the computer in front of her by clicking on a button on the screen. Her office chair has rolled back behind her.] Click [Megan stands in front of the computer arms in her sides. Beat panel.] [Zoom out with Cueball sitting in his office chair typing a reply on his computer to the message from Megan as in the first panel.] Megan (through the computer): So far, it's not actually too bad! Cueball (writing): Ahem? Megan (through the computer): Wait. Shit.

Porn

Porn

https://www.xkcd.com/598

https://www.explainxkcd.com/wiki/index.php/598:_Porn

[Cueball is hunched up at a computer. A circle surrounds him; the rest of the panel is black. The text is written in a square panel above the white circle.] I shouldn't have watched all that porn as a teenager. [The text is above the picture in a square frame. A computer screen is shown. It displays an on-line video player, with what appears to be a Cueball-like guy performing cunnilingus on a Megan-like girl. Five other windows (maybe ads) are also visible, though what they depict is not clear. One of them has readable text above a picture (of what appear to be a fleshlight). The rest of the text, including a heading at the top, is unreadable. There is picture with a lady with "big" hair holding her arms out. She has two black blotches on each side of her body. Maybe representing her breast, perhaps in a bra.] It's not that it scarred me. Ad text: X 10 [A modem is shown between the two text parts. The text is in two square frames.] It's just that we had dial-up. Modem: 14.4 kbps And now I'm stuck with a fetish. [Cueball and Megan are in bed together. The text above the picture is in a square frame.] For video compression. Cueball: Can you try to look... blockier?

Cueball 's mention of how porn did not scar him is a reference to a lot of testimony on how porn has negatively affected people's lives . Of course, the porn really did affect the way he looked at women. Due to dial-up being of such a slow speed, videos that needed to be transmitted via dial-up had to be compressed using a lossy format, which reduces file sizes substantially but also causes heavy data losses; the result being that the new decompressed file would not be of the same quality of the original uncompressed file. In this case, the lossy format eats away at the detail of the picture, which, during decompression, results in blocky artifacts in an attempt to "reconstruct" the lost data. Since he associated blocky pictures with arousal, he seems to have trouble enjoying sex with his comparatively hi-fi girlfriend. In other words, the porn really did scar him after all. The title text expands on this, referencing file corruption . It is also a pun on female "corruption," or a woman's awareness of her sexuality. [Cueball is hunched up at a computer. A circle surrounds him; the rest of the panel is black. The text is written in a square panel above the white circle.] I shouldn't have watched all that porn as a teenager. [The text is above the picture in a square frame. A computer screen is shown. It displays an on-line video player, with what appears to be a Cueball-like guy performing cunnilingus on a Megan-like girl. Five other windows (maybe ads) are also visible, though what they depict is not clear. One of them has readable text above a picture (of what appear to be a fleshlight). The rest of the text, including a heading at the top, is unreadable. There is picture with a lady with "big" hair holding her arms out. She has two black blotches on each side of her body. Maybe representing her breast, perhaps in a bra.] It's not that it scarred me. Ad text: X 10 [A modem is shown between the two text parts. The text is in two square frames.] It's just that we had dial-up. Modem: 14.4 kbps And now I'm stuck with a fetish. [Cueball and Megan are in bed together. The text above the picture is in a square frame.] For video compression. Cueball: Can you try to look... blockier?

Apocalypse

Apocalypse

https://www.xkcd.com/599

https://www.explainxkcd.com/wiki/index.php/599:_Apocalypse

[The first panel is very large and shows a dark scene with one large meteor in front and four smaller in the background showering the darkened earth. They are all five black with yellow fire around them and a fire trail behind them, and all are flying from the top left corner and down towards right. The sky at the top is pitch black, but then the sky turns blood red under dark clouds. Two large mountain peaks, one almost pyramid shaped, are shown to the left and to the right there are two smaller peaks towards the distant horizon. The mountains and the ground around them are mainly black, but with red, orange and yellow streaks spread all over the black area beneath the mountain peaks, maybe indicating fire or lava, or reflections in water or blood. At the bottom right corner a normal white panel is superimposed on this apocalyptic image.] [The smaller panel at the bottom of the first is halfway over the first panel, haflway below, and only to the right of the middle of the first panel. Beret Guy is running towards left, with his arms raised in the air.] Beret Guy: The apocalypse! The skies burn, the seas turn to blood, and the dead walk the earth! [From here a normal sequence of panels in three rows begin beneath the second panel. This leaves a gap between the apocalyptic panel and the first row of regular panels, on the left side where the 2nd panel did not reach over. In this panel Beret Guy (coming from the right) finds Cueball.] Cueball: The dead what? Beret Guy: Walk the earth! [Cueball running right in a thin panel.] Cueball: I have to go. [Cueball sitting on a chair at a table scribbling vigorously and noisily with a pen on a paper. Mathematical symbols appear above Cueball's head, including a summation from i=0 to n, a logarithm of n and the square root of a number.] ∑ n i=0 i k 1/i log(n) √163 Scribble Scribble [Cueball running right again, in a thin panel, pen and paper in hand.] [Cueball opening door with label:] Math Dept Cueball: The dead return! Cueball: Everyone, quick, get your names on here! [Cueball stand on the left side of a table looking left over his shoulder. Five people are lining up to sign the paper lying on the right side of the table. The first who signs with a pen is Blondie, then in line follows Megan, a Cueball-like guy, Ponytail and another Cueball-like guy who stand with one hand to his chin looking right, away from the other.] Blondie: At last! Guy looking right: I hope there's time! [Cueball running right in yet a thin panel, with pen and the paper flowing behind him.] [Cueball walks right with the paper and pen in his hand as he arrives at at a cemetery as revealed by an old worn sign. Scary sounds appear off-panel right.] Sign: Cemetery Rising dead (off-panel): Hurrghhh [Cueball, still going right, arrives at a grave, pen in hand and the other hand almost outside the panel, but with a corner of the paper just visible. The grave has a large gravestone to the right and in front of it there is a Cueball-like guy rising up from the ground using his arms to push up on the base of the stone and the small pile of earth towards Cueball. The guy looks very worn, with dirt on his head and scratches on his cheek.] [Cueball bends a little down and offers pen and paper to the raised dead man who looks up at him when he is addressed.] Cueball: Paul Erdős? Erdős: Yes? Cueball: We need you to sign this.

This comic begins with the beginning of the Apocalypse , hence the title. It is depicted, properly, with a very dystopian color picture with several yellow burning meteors striking down from the blood red sky, towards a black, red, orange and yellow ground. The way the panels are drawn below makes a transition from this dark image to a normal comic, with the first normal panel being superimposed on the dark image. In this image Beret Guy shouts out The apocalypse! And then he continues to explain what this will mean: The skies burn, the seas turn to blood, and the dead walk the earth! All three sentences are attributed to the apocalypse, but it seems that the first one about the sky burning, actually comes from a translation of one of the Nostradamus predictions which has, amongst others, been used to " predict 9/11 ". In Revelation 16 from the Bible about the Seven bowls , which are a set of seven plagues of God's wrath poured over the wicked towards the Apocalypse, the second bowl describes that The Sea Turns to Blood . The resurrection of the dead is from the biblical version of the Apocalypse, the Last Judgment . After Beret Guy has announced this, he runs into Cueball who has heard part of this, but he is only interested in the last part and asks to check if he understood correctly that the dead will walk the earth. When this is confirmed Cueball becomes very busy. He runs to his office and quickly writes a scientific math paper, then runs as fast as he can to the math department and get his colleagues to sign it. Then he runs to a cemetery where the dead are rising, finds the one he searched for, and asks the resurrected zombie if he is Erdős. When confirmed that he is indeed Erdős, Cueball asks him to sign the math paper. Paul Erdős (26 March 1913 – 20 September 1996) was a Hungarian mathematician who (according to Wikipedia) published more papers than any other mathematician in history, working with hundreds of collaborators. His grave is in the Kozma Street Cemetery in Budapest. There is an in-joke developed among mathematicians called the Erdős number (similar to a Bacon number for film actors, referenced in the title text, see below). By definition, Erdős has an Erdős number of 0. Everyone who has co-written a mathematical paper with Erdős has an Erdős number of 1. Everyone who collaborated with them (but not Erdős himself) is assigned an Erdős number of 2. In general, if k is the minimal Erdős number of all the people you've written papers with, your Erdős number is k + 1. The Erdős number is the length of the shortest "chain" from you to Erdős. Thanks to collaboration between mathematicians and other researchers, many people in science and medical research now have Erdős numbers. Not everyone has an Erdős number, though; people without any chain linking them to Erdős have an undefined Erdős number. For example, most people who are not mathematicians or scientists do not have Erdős numbers. Nor do mathematicians and scientists whose publications were written by themselves only with no collaborators. By this trick Cueball thinks that he and his colleagues will now all have an Erdős number of 1. The joke is that he would be using his last few hours in this life to write a math paper just to improve his and his friends' Erdős numbers. There are, however, many problems with his idea, even assuming the dead will walk the earth on that day. First of all, just having your name on a piece of paper with Erdős's signature does nothing for your Erdős number. It needs to be a scientifically valid paper , published in a peer reviewed scientific journal . And given that the apocalypse is happening, there seems no time, chance or reason to publish any more math papers. Even if there were time, it would not count for much to have someone sign a math paper they haven't even read, let alone had anything to do with the actual writing and research. The same would be true for the other five mathematicians who signed it. But of course many papers have coauthors who did not do much more than work in the same department as the person who actually wrote the paper (a sad but true fact). Presumably Cueball's friends assume that nobody will investigate whether they, or Erdős, truly participated in the writing and research of Cueball's paper. Furthermore, even if it did count, they will not be able to take the paper with them into the afterlife (although since nobody has ever returned from the afterlife [ citation needed ] we can't be certain of this), and thus since no one would have had time to read the paper, no one would know they had an Erdős number of 1. In the afterlife they could all say that they had such a number, but then again everyone else with such an interest could do the same, since no one could prove otherwise. Of course if you end up in the same part ( Heaven or Hell ) of the afterlife as Erdős he could confirm or deny the claim, but that would probably not help Cueball and his friends, since he could tell the truth about their paper. (Erdős was known for using an idiosyncratic set of slang terms, in which he described people who had stopped doing mathematics as having "died", whereas people who had died had "left".) That the whole comic is about the Erdős number, and not just Erdős signature, is made clear in the title text which refers to a similar (and less esoteric) meme called " Six Degrees of Kevin Bacon ", or simply Bacon numbers. This time, the chain's center is actor Kevin Bacon , and the links are formed by two people appearing in the same movie. Unlike Erdős, Kevin Bacon is not dead, so those of you wishing to get a Bacon number of 1 still have a chance. In the title text Cueball thus wonders if there is still time for him to make a short film with Kevin Bacon, now he has used so much time on improving his Erdős number. Again, if the film hasn't been shown to the public it would not count for anything... One of the mathematical scribbles appearing in panel 5 shows the square root of 163, which may be a reference to Ramanujan's constant . 403: Convincing Pickup Line has a parody of the Erdős collaboration graph. Zombies are a recurring theme in xkcd, particularly zombie scientists, which has also occurred both before with Richard Feynman in 397: Unscientific and after with Marie Curie in 896: Marie Curie . [The first panel is very large and shows a dark scene with one large meteor in front and four smaller in the background showering the darkened earth. They are all five black with yellow fire around them and a fire trail behind them, and all are flying from the top left corner and down towards right. The sky at the top is pitch black, but then the sky turns blood red under dark clouds. Two large mountain peaks, one almost pyramid shaped, are shown to the left and to the right there are two smaller peaks towards the distant horizon. The mountains and the ground around them are mainly black, but with red, orange and yellow streaks spread all over the black area beneath the mountain peaks, maybe indicating fire or lava, or reflections in water or blood. At the bottom right corner a normal white panel is superimposed on this apocalyptic image.] [The smaller panel at the bottom of the first is halfway over the first panel, haflway below, and only to the right of the middle of the first panel. Beret Guy is running towards left, with his arms raised in the air.] Beret Guy: The apocalypse! The skies burn, the seas turn to blood, and the dead walk the earth! [From here a normal sequence of panels in three rows begin beneath the second panel. This leaves a gap between the apocalyptic panel and the first row of regular panels, on the left side where the 2nd panel did not reach over. In this panel Beret Guy (coming from the right) finds Cueball.] Cueball: The dead what? Beret Guy: Walk the earth! [Cueball running right in a thin panel.] Cueball: I have to go. [Cueball sitting on a chair at a table scribbling vigorously and noisily with a pen on a paper. Mathematical symbols appear above Cueball's head, including a summation from i=0 to n, a logarithm of n and the square root of a number.] ∑ n i=0 i k 1/i log(n) √163 Scribble Scribble [Cueball running right again, in a thin panel, pen and paper in hand.] [Cueball opening door with label:] Math Dept Cueball: The dead return! Cueball: Everyone, quick, get your names on here! [Cueball stand on the left side of a table looking left over his shoulder. Five people are lining up to sign the paper lying on the right side of the table. The first who signs with a pen is Blondie, then in line follows Megan, a Cueball-like guy, Ponytail and another Cueball-like guy who stand with one hand to his chin looking right, away from the other.] Blondie: At last! Guy looking right: I hope there's time! [Cueball running right in yet a thin panel, with pen and the paper flowing behind him.] [Cueball walks right with the paper and pen in his hand as he arrives at at a cemetery as revealed by an old worn sign. Scary sounds appear off-panel right.] Sign: Cemetery Rising dead (off-panel): Hurrghhh [Cueball, still going right, arrives at a grave, pen in hand and the other hand almost outside the panel, but with a corner of the paper just visible. The grave has a large gravestone to the right and in front of it there is a Cueball-like guy rising up from the ground using his arms to push up on the base of the stone and the small pile of earth towards Cueball. The guy looks very worn, with dirt on his head and scratches on his cheek.] [Cueball bends a little down and offers pen and paper to the raised dead man who looks up at him when he is addressed.] Cueball: Paul Erdős? Erdős: Yes? Cueball: We need you to sign this.

Android Boyfriend

Android Boyfriend

https://www.xkcd.com/600

https://www.explainxkcd.com/wiki/index.php/600:_Android_Boyfriend

[Ponytail enters from the right dragging Hairy along by his hand, as she moves towards Cueball who stands with Megan in his hand.] Ponytail: I thought your android girlfriend was cool so I got myself an android boyfriend. [Suddenly the Megan android runs into the arms of the Hairy android, while Ponytail has let go of his hand. Ponytails head swirls around to follow her run by.] Ponytail: He's really great. I like how— Ponytail: Uh. [Cueball and Ponytail look towards the two androids, but they are now outside this frame-less panel.] Off-panel sound: *Zip* Off-panel voice: Mmmmm [Cueball and Ponytail still look at the scene off panel.] Cueball: ...Huh. Ponytail: It's like somebody stuck a vibrator in a fleshlight. Off-panel sound: Whirrr Off-panel voice: Mmmm Off-panel sound: Click This is the comic six years before 1541: Voice , in which Ponytail stated that she could only control her voice once every six years.

This is the second (and last) comic in the Android series , referring directly back to 595: Android Girlfriend , where Cueball showed that he had an android girlfriend Megan . So now Ponytail has decided she would also like to have an android boyfriend ( Hairy ). But upon bringing these two androids together, they fall for each other and decide to have "sex" on the spot, resulting in several mechanical sounds off-panel while their "owners" watch on with disgusted interest. Vibrators and Fleshlights are sex toys that represent male and female genitalia, respectively. Ponytail's flat description indicates that she is not particularly aroused by what amounts to a pair of animatronic sex toys rubbing against each other. Randall's title text claims that he has actually done such a thing, and stuck it on his fireplace mantle for all his house-guests to see. He admits though that it is the most unsettling mantlepiece decoration in my house. References to fleshlights is a recurring theme in xkcd. [Ponytail enters from the right dragging Hairy along by his hand, as she moves towards Cueball who stands with Megan in his hand.] Ponytail: I thought your android girlfriend was cool so I got myself an android boyfriend. [Suddenly the Megan android runs into the arms of the Hairy android, while Ponytail has let go of his hand. Ponytails head swirls around to follow her run by.] Ponytail: He's really great. I like how— Ponytail: Uh. [Cueball and Ponytail look towards the two androids, but they are now outside this frame-less panel.] Off-panel sound: *Zip* Off-panel voice: Mmmmm [Cueball and Ponytail still look at the scene off panel.] Cueball: ...Huh. Ponytail: It's like somebody stuck a vibrator in a fleshlight. Off-panel sound: Whirrr Off-panel voice: Mmmm Off-panel sound: Click This is the comic six years before 1541: Voice , in which Ponytail stated that she could only control her voice once every six years.