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Limerick

Limerick

https://www.xkcd.com/301

https://www.explainxkcd.com/wiki/index.php/301:_Limerick

[Cueball sits at a computer, typing.] Cueball (typing): I used to find slashdot delightful, Cueball (typing): but my feelings of late are more spiteful; Cueball (typing): my comments sarcastic Cueball (typing): the iconoclastic Cueball (typing): keep modding to plus five (Insightful).

A limerick is a well-known type of poem that is usually humorous or bawdy. Technically, a limerick is primarily anapestic trimeter : each line contains three "feet," each foot consisting of two unstressed syllables followed by a stressed syllable. The rhyme scheme is AABBA: the first, second, and fifth lines rhyme, as do the shorter third and fourth lines. Almost anyone can instantly recognize a limerick after hearing the first line. Slashdot is a venerable techie site. On many sites, the user base can vote comments "up" or "down," but at Slashdot, only moderators (these are randomly drawn from the pool of registered users) may up or down vote comments, and the moderator may select a reason for their up or down vote. Instead of a simple +1, a comment may be voted +1 (Funny). Similarly, instead of -1, a comment may be voted -1 (Off-topic). +5 is the maximum positive score. A comment rated +5 (Insightful) has been upvoted at least 5 times, and has a plurality of "Insightful" votes. Cueball 's limerick says that he does not like Slashdot anymore, because his sarcastic comments are being treated as "insightful" by the very people he's being sarcastic to. The title text refers to the notoriously awful comments on YouTube, many of which are so idiotic that they're interpreted as jokes. In both cases, Randall is invoking Poe's Law . Both sites have become so full of extremes that you can no longer mock the extremists without looking like a sincere extremist yourself. 301, the number of this comic, is also a number often associated with YouTube. At the time this comic was published, view counts on YouTube videos would often freeze at 301, as YouTube would switch between view-counting algorithms when the number of views exceeded 300. Therefore, the comic number itself may be a reference to the title text. [Cueball sits at a computer, typing.] Cueball (typing): I used to find slashdot delightful, Cueball (typing): but my feelings of late are more spiteful; Cueball (typing): my comments sarcastic Cueball (typing): the iconoclastic Cueball (typing): keep modding to plus five (Insightful).

Names

Names

https://www.xkcd.com/302

https://www.explainxkcd.com/wiki/index.php/302:_Names

Cueball (thinking): I hate it when I don't know someone's name, but it's been long enough that it's too awkward to ask. [The scene is revealed to be at the altar getting married by a minister to a woman in a bridal dress.] Minister: Do you Rachel, take this man... Cueball (thinking): Aha! Rachel!

Everyone has had moments where they forget someone's name, even the name of someone pretty important. This doesn't often happen with one's own significant other, however, hence the joke. Cueball has been in a relationship with someone but does not know his girlfriend's name. He knows that the relationship has progressed to the point where asking for her name would be awkward and impolite, and so he waits for someone to call her by name. Cueball is excited when one finally does, only to reveal that they are in the middle of a wedding ceremony. It is hard to be in a relationship with someone if you don't know their name, and for said relationship to progress to the point of a wedding is simply incredulous. [ citation needed ] It's sometimes tricky to say the right things during an introduction, and while making sure you don't make an incorrect response (replying to the question "How're you doing?" with "Not much," for example, mishearing the question as "What are you doing?"), one can sometimes forget to pay attention to the actual important part of the introduction: the person's name. And it's awkward to ask someone for their name when you should, by all rights, already know it. Forgetting people's names is a frequent symptom of various social anxiety disorders, but it can happen to anybody at any time. Cueball (thinking): I hate it when I don't know someone's name, but it's been long enough that it's too awkward to ask. [The scene is revealed to be at the altar getting married by a minister to a woman in a bridal dress.] Minister: Do you Rachel, take this man... Cueball (thinking): Aha! Rachel!

Compiling

Compiling

https://www.xkcd.com/303

https://www.explainxkcd.com/wiki/index.php/303:_Compiling

The #1 Programmer Excuse for Legitimately Slacking Off: "My code's compiling." [Two programmers are sword-fighting on office chairs in a hallway. An unseen manager calls them back to work through an open office door.] Manager: Hey! Get back to work! Cueball: Compiling! Manager: Oh. Carry on.

Computer programming involves writing instructions for a computer to follow, in a specific programming language , which is largely human readable and writable, at least to programmers who understand that language. However, for the computers to follow instructions, they need to be given machine code — the actual "language" that computers "speak" and one that can be written directly with the correct tools, but would be too tedious and error-prone for just about any practical modern project where alternatives exist, where anything more than a Hello World could be awkward to implement straight into machine-code. Conversion from the more conveniently human-writable code into computer-executable files is performed by assemblers , interpreters , or compilers . Programs can be written in assembly code , which is basically just a set of mnemonics that make machine code much easier for a human to remember and correctly parse; the human-written assembly code is then run through a simple assembler to convert it directly into machine code. Assembly coding is necessary whenever one is programming for a completely new architecture (one for which no other tools yet exist), and is still used in some other situations (as it allows the code to be optimized more closely for the system on which it is to run than is possible with other types of coding), but is still fairly tedious and error-prone, and assembly code needs to be completely rewritten if one wants to port it to a computer with a different architecture. Interpreters (e.g. that for PHP for one example) generally read through the code, or script, each line at a time as and when required, and has to do a lot of work with various processing overheads and the risk of hitting an invalid instruction or mistake in syntax that it can't handle. It also requires that a relevant version of the interpreter exist on any machine that has to run the script and perhaps some additional knowledge by the end-user. For widely distributed (and especially commercial) programs, some form of compilation will instead be used. Compiling may have just one computer system read through the man-written code and (barring errors) produces the equivalent stand-alone and direct machine-readable code, suitable for a given range of computers. This process might involve several passes to check for 'obvious' errors in the code, as well as converting some programming concepts that are easiest for humans to understand into equivalent concepts that may be far easier for the computer to work with. As such, compiling takes a certain amount of time at the time of production. Normally, this takes a few seconds, but, depending on the size of the project and the power of the computer doing the compilation, the time required to compile a program may measure in minutes, or even hours. As of 2015, the Linux Kernel contains over 19 million lines of code, arguably a massive job for any compiler, but if done correctly, it saves time for all the people who will ultimately be using its output. Thus, when Cueball is caught wasting time at work, he argues that such activities are not worse than any other possible ones, at this moment. If his job is writing code and compiling it, then there may be nothing else that he can do right now. He cannot usefully tweak the code before it finishes compiling and the expected result checked. The title text takes this a step further. Cueball claims that all activities are equally benign while the code is compiling — and that includes committing illegal acts, such as stealing LCDs . Nine years after this comic was released, Randall made a comic called 1755: Old Days about how compiling worked in the old days. It was Cueball who asked. The next comic after that, 1756: I'm With Her , was released the Monday before the 2016 United States presidential election . And in that comic, a Cueball with a sword on an office chair like in this comic is featured. Seems realistic that Randall had that politically loaded comic ready for some time, and when finding and deciding to use this old version of Cueball, he may have gotten inspired by the compiling theme to make Old Days. The #1 Programmer Excuse for Legitimately Slacking Off: "My code's compiling." [Two programmers are sword-fighting on office chairs in a hallway. An unseen manager calls them back to work through an open office door.] Manager: Hey! Get back to work! Cueball: Compiling! Manager: Oh. Carry on.

Nighttime Stories

Nighttime Stories

https://www.xkcd.com/304

https://www.explainxkcd.com/wiki/index.php/304:_Nighttime_Stories

[Cueball sitting in an armchair in a darkened room, with a bookshelf and an open window. Megan is seen outside reading a book by a glow.] For a few weeks now, sometime past midnight, a girl has wandered past my apartment reading by flashlight. [Outside, Megan walking down the street passing under a street lamp.] I wonder why she's up so late. Maybe she's restless Like me. I wonder what story she's wrapped up in. I wonder if she lets anyone into that island of light. [Cueball sitting in a dark room.] [Cueball has left the room.] [Cueball standing on his doorstep at the top of a small flight of stairs, near the bottom of which Megan has stopped, no longer reading.] Cueball: Hi! What are you reading? Megan: Orson Scott Card's 'Xenocide.' It's my favorite in the series! Cueball: Wait, you like it more than Speaker for the Dead or Ender's Game? Megan: Yeah! [Cueball has gone back in the house, leaving Megan standing alone.] [Cueball is sitting in the chair again.] And to think I loved her.

Cueball observes Megan walking around at midnight, reading a book that he can't see. Curious, he leaves his apartment to ask her what she is reading. It is revealed as Orson Scott Card 's Xenocide , the third book in the Ender's Game series following Ender's Game and Speaker for the Dead (and since followed by several other books). Ender's Game has been covered in other xkcd comics like 241: Battle Room and 635: Locke and Demosthenes , which cover events in the first book. Xenocide is regarded by fans as one of the weakest books in the series, while Ender's Game and Speaker for the Dead received extreme positive praise. When he discovers that she likes Xenocide more than the other two books, he instantly withdraws to his apartment, his opinion of her shattered. So far as Cueball is concerned, Xenocide is so clearly inferior that he could not be with anyone who 'wrongly' considers it to be the best of the series. This pokes fun at people like Cueball who have such strong opinions on books like Ender's Game that they could never get along with anyone who disagreed. The title text pokes further fun at Xenocide by saying that there are only seven people in the world who would defend it, a laughably small number. [Cueball sitting in an armchair in a darkened room, with a bookshelf and an open window. Megan is seen outside reading a book by a glow.] For a few weeks now, sometime past midnight, a girl has wandered past my apartment reading by flashlight. [Outside, Megan walking down the street passing under a street lamp.] I wonder why she's up so late. Maybe she's restless Like me. I wonder what story she's wrapped up in. I wonder if she lets anyone into that island of light. [Cueball sitting in a dark room.] [Cueball has left the room.] [Cueball standing on his doorstep at the top of a small flight of stairs, near the bottom of which Megan has stopped, no longer reading.] Cueball: Hi! What are you reading? Megan: Orson Scott Card's 'Xenocide.' It's my favorite in the series! Cueball: Wait, you like it more than Speaker for the Dead or Ender's Game? Megan: Yeah! [Cueball has gone back in the house, leaving Megan standing alone.] [Cueball is sitting in the chair again.] And to think I loved her.

Rule 34

Rule 34

https://www.xkcd.com/305

https://www.explainxkcd.com/wiki/index.php/305:_Rule_34

Cueball: Huh-- Thomas the Tank Engine slash fiction. Megan: It's rule 34 of the internet. If you can imagine it, there is porn of it. Cueball: Nah. The web is freaky, but it can't begin to have everything. Cueball: There's no porn set atop storm-chasing vans. No homoerotic spelling bees. No women playing electric guitar in the shower. Megan: Actually, that last one would look pretty hot. As long as they were unplugged or waterproofed... Megan: Rivulets of water run down her chest, the smooth body of the guitar firm against her hips. Megan: She twangs the E-string and it shakes off tiny droplets in all directions. [She rises into a crouch.] Megan: You're sure it doesn't exist? Cueball: Not yet. Megan: I'm registering WetRiffs.com. Let's get on this.

Cueball is rather surprised to find slash fiction (same-sex erotic fiction featuring characters from popular media, often from unrelated series) featuring characters from the Thomas the Tank Engine television series, but Megan isn't remotely surprised, citing Rule 34 : "If it exists, there is porn of it. No exceptions." Cueball denies the truism of the rule, coming up with several examples of porn that doesn't exist yet, until he comes across one that they both agree would be pretty hot: Women playing electric guitar in the shower. Megan proceeds to get ahead of the curve by registering WetRiffs.com. By doing this, Megan invoked Rule 35 , an additional rule based around rule 34. Rule 35 states: "If there is not porn of it, porn will be made of it." In the title text, we can assume that the presenter in a spelling bee is asking a male participant with the name "Lance" to spell " throbbing ," a term sometimes used to describe the swelling of a person's genitals. The scene thus plays out like the start of a hypothetical homoerotic spelling bee that could contain rude words or innuendo. Rule 34 is mentioned in the title text of 505: A Bunch of Rocks and 860: Never Do This . Cueball: Huh-- Thomas the Tank Engine slash fiction. Megan: It's rule 34 of the internet. If you can imagine it, there is porn of it. Cueball: Nah. The web is freaky, but it can't begin to have everything. Cueball: There's no porn set atop storm-chasing vans. No homoerotic spelling bees. No women playing electric guitar in the shower. Megan: Actually, that last one would look pretty hot. As long as they were unplugged or waterproofed... Megan: Rivulets of water run down her chest, the smooth body of the guitar firm against her hips. Megan: She twangs the E-string and it shakes off tiny droplets in all directions. [She rises into a crouch.] Megan: You're sure it doesn't exist? Cueball: Not yet. Megan: I'm registering WetRiffs.com. Let's get on this.

Orphaned Projects

Orphaned Projects

https://www.xkcd.com/306

https://www.explainxkcd.com/wiki/index.php/306:_Orphaned_Projects

[Voices are coming from behind a door with a sign that reads "Debian Linux HQ."] First voice: Problem: One of the volunteer developers has a date this weekend. Dates lead to romance, romance leads to orphaned projects. Second voice: What's the plan? First voice: We're hiring him a relationship coach. He's like Will Smith in "Hitch," but he only gives bad advice. [Black Hat is talking to Cueball, who is standing in front of a mirror.] Black Hat: Okay, remember: The key to conversation is constructive criticism. Black Hat: You need to show you're smart enough to solve her problems. Cueball: Makes sense.

Debian is a GNU/Linux distribution (but also ships GNU Hurd and BSD versions). Red Hat is the company behind Fedora Linux and RHEL . The comic is about orphaned Linux projects, because volunteer FOSS developers will often leave their projects aside whenever something of greater importance to them requires more time (like dating, relationships, tiredness, sickness, boredom, natural disasters, wild boar attacks, zombie apocalypses, robot uprisings, desire for snacks, etc.). Some companies/foundations, while not needing these developers, can greatly benefit from community-maintained projects. The Debian Team uses a phrase that is, intentionally or otherwise, similar to the famous Yoda quote from Star Wars: Episode I – The Phantom Menace in the first panel "Fear leads to anger. Anger leads to hate. Hate leads to suffering," by replacing it with dating and orphaned projects. Hitch is a romantic comedy in which Will Smith plays a "dating coach," who helps men to have successful dates with women. To avoid losing their developers (in this case, Cueball), the people at the "Debian HQ" have opted to hire Black Hat to give the developer intentionally bad dating advice, thus sabotaging his relationship before it could become distracting. Cueball is advised to "constructively criticize" his date in an attempt to appear more intelligent. This technique is very unlikely to work, but is nonetheless attempted by some men. It is unclear whether this is "negging" (See 1027: Pickup Artist ) or simply a demonstration of hubris, neither of which would be an attractive attribute in a potential long-term partner or mate. [ citation needed ] In the title text, the woman is being similarly advised by a representative hired by Red Hat. She is advised to rent lots of romantic comedies, presumably to watch with her date. The prevailing stereotype is that young men strongly dislike films in that genre. [Voices are coming from behind a door with a sign that reads "Debian Linux HQ."] First voice: Problem: One of the volunteer developers has a date this weekend. Dates lead to romance, romance leads to orphaned projects. Second voice: What's the plan? First voice: We're hiring him a relationship coach. He's like Will Smith in "Hitch," but he only gives bad advice. [Black Hat is talking to Cueball, who is standing in front of a mirror.] Black Hat: Okay, remember: The key to conversation is constructive criticism. Black Hat: You need to show you're smart enough to solve her problems. Cueball: Makes sense.

Excessive Quotation

Excessive Quotation

https://www.xkcd.com/307

https://www.explainxkcd.com/wiki/index.php/307:_Excessive_Quotation

[Outside, under a crescent moon.] Megan: It's strange to stare at the moon and think about people walking on it. Cueball: That's no moon, it's a— gack [She holds him up in the air by his neck à la Darth Vader using the force.] Megan: I find your lack of original conversation disturbing.

Megan just wants to have a normal conversation about the moon, but Cueball replies with a quote from Star Wars: Episode IV – A New Hope , wherein Obi-Wan Kenobi says: "That's no moon, that's a space station." Megan cuts him off in the manner of another Star Wars character, the villain Darth Vader , and showing a glimmer of the character's abilities, proceeds to choke him with The Force while modifying another phrase from the same film. (The original quotation was, "I find your lack of faith disturbing.") There is humor in Megan's hypocrisy, however. Although she is disturbed by Cueball's unoriginal dialogue, she is fine with doing it herself. Star Wars fans are a weird bunch, however, and the title text states that if a male Star Wars fan met a girl who could do this in real life, it'd only serve to turn him on even more. [Outside, under a crescent moon.] Megan: It's strange to stare at the moon and think about people walking on it. Cueball: That's no moon, it's a— gack [She holds him up in the air by his neck à la Darth Vader using the force.] Megan: I find your lack of original conversation disturbing.

Interesting Life

Interesting Life

https://www.xkcd.com/308

https://www.explainxkcd.com/wiki/index.php/308:_Interesting_Life

[On the left hand side of the panel is a cutaway of several floors of an office, in gray. On the right side, a blue sky with clouds, and green hills below. Hanging from a cable is Megan, clearly having rappelled down the side of the building, next to a Cueball at his desk, who is looking at Megan.] Megan: You know how some people consider "May you have an interesting life" to be a curse? Cueball: Yeah... Megan: Fuck those people. Wanna have an adventure?

' May you live in interesting times ' (or, in this comic, 'may you have an interesting life') is supposedly a Chinese saying, except that a few people (usually the worst-case-scenario kind) believe it to actually be a curse, even though it is usually meant in a good way when said. The quote also provides the title of the Terry Pratchett novel Interesting Times , which takes place in a fictional counterpart of China. Cueball is shown here as an office worker, a job that, to most people, is the opposite of interesting. This is contrasted with Megan , who is rappelling down the outside of his office building, for no apparent reason other than because she can, and inviting him on an adventure. Things are bound to get at least one kind of "interesting" very fast. The title text refers to a Cat6 cable, which is more commonly known as Ethernet cable. It would be easily found in an office building, since it is used to connect computers to a network. Its usefulness as a climbing harness is indeterminate. [ citation needed ] [On the left hand side of the panel is a cutaway of several floors of an office, in gray. On the right side, a blue sky with clouds, and green hills below. Hanging from a cable is Megan, clearly having rappelled down the side of the building, next to a Cueball at his desk, who is looking at Megan.] Megan: You know how some people consider "May you have an interesting life" to be a curse? Cueball: Yeah... Megan: Fuck those people. Wanna have an adventure?

Shopping Teams

Shopping Teams

https://www.xkcd.com/309

https://www.explainxkcd.com/wiki/index.php/309:_Shopping_Teams

[Three teams are looking at a counter with two cubes on it. Above it all is written in very large letters:] Shopping teams [Above the first team consisting of two Cueball-like guys is written the following text (the first line written with larger letters):] Bad: Two non-nerds Non-nerd 1: Let's get that one. Non-nerd 2: Okay. [Above the second team consisting of a Blondie and a Cueball-like guy is written the following text (the first line written with larger letters):] Good: Non-nerd + nerd Blondie non-nerd: Let's get that one. Cueball nerd: Wait, I think that one might be a better deal. Blondie non-nerd: Okay, that one. [Above the third team consisting of two Cueball-like guys is written the following text (the first line written with larger letters):] Very Bad: Two Nerds Nerd 1: How about that one? Nerd 2: I think the other one might be the better deal... Nerd 1: Hmm, I'm not sure... [Inside a big arrow pointing straight down:] Two Hours Later [The two Cueball-like guys are sitting on the floor in front of the counter, both having their laptops open and with lots of paper sheets spread around them, as well as a pen. Blondie from the second team comes in from the right and raises her arms:] Nerd 1: I think our main problem is our unclear definition of value. Blondie non-nerd: That is not your main problem!

Randall is comparing the ways different people look at choosing between similar products. In the first example, which Randall considers "bad," two "non-nerds" look at two products (without a description of any kind) and instantly decide which one they want. In the second example, which is considered "good," one of the two is a nerd , and the other one is a non-nerd. The non-nerd instantly picks one of the products, but the nerd evaluates the two and decides that the other one is better because it's a better deal. In both the first two cases, the pair is able to easily come to a decision. However, in the third example, two nerds are comparing the two boxes, and both of them overanalyse the various merits and drawbacks on each of the two boxes. They are still there two hours later, unable to reach a clear agreement on which of the two boxes they wish to buy. One nerd comments that their definition of value is unclear, suggesting that the discussion has gone on for so long because they are re-evaluating their definitions over something too trivial. Some might perceive this as typical "nerd" behaviour, overanalysing a problem that is in actual fact quite trivial, such as the decision whether to buy one box or the other virtually identical box. The non-nerd woman from the second situation (or perhaps the store manager in this situation), who has watched the two nerds compare the two products for hours, attempts to put this into perspective by pointing out that an unclear definition of value is not their main problem. The implication is that their real main problem is that they are unable to reach an agreement on something that makes so little difference. Or their problem could be the one described in 1445: Efficiency . The title text suggests that Randall entered a similar situation attempting to buy an air conditioner with his sysadmin, short for System administrator . The sysadmin is a person in an organization employed to manage the computer system or network, a role that requires technical skills and intelligence. The suggestion here is that a computer programmer, like Randall, put together with a sysadmin, would spend as much attention to detail as the two nerds in the comic, laboring over which of two trivially similar products to buy. Randall deals with sysadmins again in 705: Devotion to Duty . [Three teams are looking at a counter with two cubes on it. Above it all is written in very large letters:] Shopping teams [Above the first team consisting of two Cueball-like guys is written the following text (the first line written with larger letters):] Bad: Two non-nerds Non-nerd 1: Let's get that one. Non-nerd 2: Okay. [Above the second team consisting of a Blondie and a Cueball-like guy is written the following text (the first line written with larger letters):] Good: Non-nerd + nerd Blondie non-nerd: Let's get that one. Cueball nerd: Wait, I think that one might be a better deal. Blondie non-nerd: Okay, that one. [Above the third team consisting of two Cueball-like guys is written the following text (the first line written with larger letters):] Very Bad: Two Nerds Nerd 1: How about that one? Nerd 2: I think the other one might be the better deal... Nerd 1: Hmm, I'm not sure... [Inside a big arrow pointing straight down:] Two Hours Later [The two Cueball-like guys are sitting on the floor in front of the counter, both having their laptops open and with lots of paper sheets spread around them, as well as a pen. Blondie from the second team comes in from the right and raises her arms:] Nerd 1: I think our main problem is our unclear definition of value. Blondie non-nerd: That is not your main problem!

Commitment

Commitment

https://www.xkcd.com/310

https://www.explainxkcd.com/wiki/index.php/310:_Commitment

[Cueball proposing on his knee holding a box with a ring in it up to a girl with long blond hair. The text is written above them in a frame with yellow background.] I understand now. There's no choir of angels when you meet the right person. It's about growing out of your fears to realize what you have is what you want. [Cueball and the woman are getting married. They stand under a gate of honor with a priest in front of them.] Girl: I do. Cueball: I do. [Cueball walks hand in hand with blond girl when a cloud with trumpeting angels appears over Megan.] Megan: Hi. [Same picture but without the cloud and angels. Cueball's thought is written in a frame with yellow background.] Well, shit.

In the first panel, Cueball proposes to a woman. While he does this, a narrator (most likely the man's inner voice) explains why he wants to marry her. It's implied that he had doubts about their relationship. He'd never experienced a moment of overwhelming love and certainty, especially when they met, which he describes as "a choir of trumpeting angels when you meet the right girl." He's come to believe that such a scenario is actually implausible, and a serious relationship is about "realizing that what you have is what you want." In the second panel, they get married. And in the third panel, after they are married, Megan comes in saying 'Hi.' His wife appears to still be wearing her wedding veil, implying that he meets Megan immediately after the scenario. Cueball has the full 'love at first sight'-experience, with a literal choir of trumpeting angels, suggesting that Megan is actually the one he's supposed to be with. That this realization strikes him immediately after he married someone else puts him in a very difficult situation. This is expressed by him thinking 'Well, shit.' The title text notes that the previous guy who had a similar experience fell in love with one of the angels instead, not realizing that it was the girl he just met that was the love of his life. Which is of course much worse, especially because the angels are transient, and the only way to see them again is by meeting the perfect 'girl' and he has just ignored her! Alternatively, it could mean that that person was actually the last person to have such an experience, possibly because the persons succeeded in marrying and having children with the angel, resulting in offspring that were too powerful or otherwise undesirable. Something similar happens in Genesis 6:1–4, so this may be a reference to the Bible. The humor of this comic plays upon a common anxiety in trying to build relationships. A person may be dating someone who they enjoy being with, but expect a moment of supernatural clarity announcing that they've found the right person to spend their life with. Most people never have such a moment, and have to build their relationships slowly, based on more prosaic considerations, like compatibility, commitment, and shared life goals. Frequently, people will build such a relationship, but worry that a magic and transcendent love is still out there, and if they 'settle' for the person they're with, they may find that love later and be unable to act on it. The comic 584: Unsatisfied could be seen as a continuation of this - with the blond girl being depicted as Ponytail . It can also be seen as a deconstruction: in the subsequent comic, no matter which partner he chooses, he spends the rest of his life thinking about the other, apparently never being totally satisfied with the relationship he has. [Cueball proposing on his knee holding a box with a ring in it up to a girl with long blond hair. The text is written above them in a frame with yellow background.] I understand now. There's no choir of angels when you meet the right person. It's about growing out of your fears to realize what you have is what you want. [Cueball and the woman are getting married. They stand under a gate of honor with a priest in front of them.] Girl: I do. Cueball: I do. [Cueball walks hand in hand with blond girl when a cloud with trumpeting angels appears over Megan.] Megan: Hi. [Same picture but without the cloud and angels. Cueball's thought is written in a frame with yellow background.] Well, shit.

Action Movies

Action Movies

https://www.xkcd.com/311

https://www.explainxkcd.com/wiki/index.php/311:_Action_Movies

[Cueball and Megan are talking together as they walk away from a cinema.] Cueball: Another summer gone without a mindless big-budget action movie. Megan: Huh? Die Hard was nothing BUT action! Cueball: No, it was too talky. Megan: What? Too talky? Cueball: I tallied it minute-by-minute. It's at least 60% people walking and talking. ALL those movies are. Cueball: Just once, I want a real action movie. 30 seconds of exposition followed by a perfect 90-minute action scene. One with a huge budget, a good choreographer, and a great director. Megan: And they should center it around some character we already know, someone we never get tired of watching. Cueball: I think we've got something here... [A movie poster is shown.] Coming this summer River Tam Beats up EVERYONE [The poster shows a line of doorways. In the background, numerous people are lying on the ground or draped over doorways and windows. River Tam is doing a flying kick into someone's face, and another person is emerging from the doorway closest to the viewer.]

A common complaint about action films is that they are light on plot and heavy on pointless violence and special effects. The Die Hard series (including Live Free or Die Hard ) are typical action films about which this complaint has been made. However, Cueball reverses the complaint, stating that proportional to the run-time of the movie, there could have been much more action and much less plot. He takes this idea to an extreme, saying that his ideal action movie should have only half a minute of exposition and otherwise consist of nothing but one long, continuous action scene. Megan adds that starring a well-known and popular character - one that audiences "never get tired of watching" - would further eliminate the need for exposition and provide more time for action. The two come up with "River Tam Beats Up Everyone" as such a movie. It is unclear if this is the actual title of their proposed movie or simply a description or teaser. In either case, the name doubles as a more or less complete plot description. River Tam (played by Summer Glau ) is a character from the popular but short-lived TV series Firefly . In the show, she is shown to have almost clairvoyant mental capabilities (including being able to read minds and aim a gun without looking), and the series largely revolves around a conspiracy concerning her. In the follow-up movie Serenity , River also possesses superhuman fighting skills - early in the film, triggered by a subliminal message, she unexpectedly begins attacking everyone in a bar. Later, in the film's climax, she subdues an entire squadron of Reavers while hardly breaking a sweat. The poster art for "River Tam Beats Up Everyone" is almost certainly inspired by these scenes from Serenity , and Megan and Cueball's decision to use River is based on her rampant popularity among the Firefly fan base. The poster's typeface, Papyrus , has also been used in many of the marketing materials for both Firefly and Serenity ; Randall would later confess his love for it in the title text of 590: Papyrus . In the title text, Randall states that Live Free or Die Hard had far too little action and suggests another movie, Crank , as a better example. He goes on to suggest that Crank would have been better if it had had a larger budget and starred Summer Glau in a fighting role. [Cueball and Megan are talking together as they walk away from a cinema.] Cueball: Another summer gone without a mindless big-budget action movie. Megan: Huh? Die Hard was nothing BUT action! Cueball: No, it was too talky. Megan: What? Too talky? Cueball: I tallied it minute-by-minute. It's at least 60% people walking and talking. ALL those movies are. Cueball: Just once, I want a real action movie. 30 seconds of exposition followed by a perfect 90-minute action scene. One with a huge budget, a good choreographer, and a great director. Megan: And they should center it around some character we already know, someone we never get tired of watching. Cueball: I think we've got something here... [A movie poster is shown.] Coming this summer River Tam Beats up EVERYONE [The poster shows a line of doorways. In the background, numerous people are lying on the ground or draped over doorways and windows. River Tam is doing a flying kick into someone's face, and another person is emerging from the doorway closest to the viewer.]

With Apologies to Robert Frost

With Apologies to Robert Frost

https://www.xkcd.com/312

https://www.explainxkcd.com/wiki/index.php/312:_With_Apologies_to_Robert_Frost

[A not-very-realistic view of the universe, in profile. To the left, a sectional view of the Earth, with its Moon and few clouds overhead, and a little Cueball standing, looking up. Extending to the right of the Earth, various stellar objects: some planets, some spaceships, another galaxy. Above them, on an artistically jagged white background, somewhat like a torn piece of paper, this text:] A God's Lament Some said the world should be in Perl; Some said in Lisp. Now, having given both a whirl, I held with those who favored Perl. But I fear we passed to men A disappointing founding myth, And should we write it all again, I'd end it with A close-paren. [To the right of the "various stellar objects", as if paired with the Earth at their left to bracket them, is a giant close parenthesis:] )

This comic presents a poem about a god 's dilemma of whether to create the world using Perl or Lisp , two popular computer programming languages. The god has chosen to write it in Perl, but since then appears to lament the choice, apparently expressing that if given the chance to write the world's code again, they would use Lisp instead. The implication is that a universe created by Lisp would look better under close examination, the 'founding myth' referred to in the poem. Instead of an incomprehensible big bang , inflation , dark matter , and dark energy , the elegance of Lisp may have led to more elegantly framed laws of nature. The grammar of Lisp as a language requires the programmer to use a multitude of parentheses and, in many cases, it can be difficult to determine whether all of the parentheses have been properly matched up to one another. The last two lines of the poem refer to the plentiful parentheses in Lisp, and the image at the bottom of the panel shows a close-parenthesis at the supposed end of the Universe. A segmentation fault, also commonly called a segfault, is an error that occurs when a computer program attempts to access computer memory to which it should not have access. This is a fatal error that will cause the program to stop executing. This comic deals with similar subject matter to 224: Lisp , in which one of "the gods" claims that although the Universe may appear to have been written in Lisp, it was actually written mostly using Perl. The poem itself and the title text are a parody of " Fire and Ice ," written by the American poet Robert Frost and first published in 1920. In this poem, the speaker discusses his stance in the debate on whether the world will be destroyed in fire or in ice. "A God's Lament" has a rhyme scheme that is nearly identical to that of Frost's poem. However, it differs in that "Lisp" does not rhyme with "men," "again," and "paren," while the corresponding four lines in Frost's poem do rhyme. (That said, "Lisp" does have a near-rhyme in "myth" and "with," especially if you say "Lisp" with a lisp.) [A not-very-realistic view of the universe, in profile. To the left, a sectional view of the Earth, with its Moon and few clouds overhead, and a little Cueball standing, looking up. Extending to the right of the Earth, various stellar objects: some planets, some spaceships, another galaxy. Above them, on an artistically jagged white background, somewhat like a torn piece of paper, this text:] A God's Lament Some said the world should be in Perl; Some said in Lisp. Now, having given both a whirl, I held with those who favored Perl. But I fear we passed to men A disappointing founding myth, And should we write it all again, I'd end it with A close-paren. [To the right of the "various stellar objects", as if paired with the Earth at their left to bracket them, is a giant close parenthesis:] )

Insomnia

Insomnia

https://www.xkcd.com/313

https://www.explainxkcd.com/wiki/index.php/313:_Insomnia

[It is black, except a few blue and green lights, and red numbers from a clock.] [The clock shows 4:31] Lying awake at night I realize how many little lights there are in my room. The alarm clock is the brightest. Can't sleep I'm alone with those glowing red numbers [The clock now shows 4:32] Time slows Does time even exist here? Thoughts churning in on themselves [The clock now shows 4:33] The madness can't be far away Ah yes [The clock now shows 13:72] There it is.

Simply put, the narrator's insomnia, combined with small bright lights in an otherwise pitch-black room, is causing him to hallucinate. Furthermore, the narrator is well aware that he will be unable to distinguish the hallucinations from reality. This finally occurs when his clock reads 13:72, which would not be possible on any clock. A clock can never read "72 minutes," as there are only 60 minutes in an hour. While a clock can read "13 hours" on a 24-hour clock (which is common on most digital clocks in Europe, but not in the US), the thirteenth hour does not occur immediately after the fourth hour. [ citation needed ] The title text shows that the narrator has indeed "succumbed" to his visions, and is assigning gibberish values — an alarm clock with a "cinnamon" setting, the time of day "25 hours and 131 minutes," and "levitation class" — to an otherwise normal monologue. [It is black, except a few blue and green lights, and red numbers from a clock.] [The clock shows 4:31] Lying awake at night I realize how many little lights there are in my room. The alarm clock is the brightest. Can't sleep I'm alone with those glowing red numbers [The clock now shows 4:32] Time slows Does time even exist here? Thoughts churning in on themselves [The clock now shows 4:33] The madness can't be far away Ah yes [The clock now shows 13:72] There it is.

Dating Pools

Dating Pools

https://www.xkcd.com/314

https://www.explainxkcd.com/wiki/index.php/314:_Dating_Pools

[Megan is sitting on the ground with her elbows on her knees and her hands on her chin.] Megan: This sucks. The median first marriage age is 26. The pool of singles is shrinking. I'm running out of time. Cueball: Actually, not quite. Cueball: Yes, older singles are rarer. But as you get older, the dateable age range gets wider. An 18-year-old's range is 16–22, whereas a 30-year-old's might be more like 22–46. Text on chart: Standard creepiness rule: Don't date under (Age/2 + 7) Cueball: I did some analysis of this with the Census Bureau numbers just last weekend. Your dating pool actually grows until middle age. So don't fret so much! [The first chart is labeled "Singles" and is a decreasing graph. The second graph is labeled Dating Pool, and is a bell curve.] Megan: Did your analysis say anything about the dating prospects of people who spend weekends at home making graphs? Cueball: Come on. Somewhere at the edge of the bell curve is the girl for me.

Megan is upset because she is apparently older than 26, and among people who marry, half do so below 26. The intuitive conclusion is that the number of potential partners is decreasing as time goes on. The Half Plus Seven Rule is an unwritten rule that asserts that it is creepy to date anyone who is younger than half your age plus 7 years. For example, a 50-year-old dating someone who is younger than 32 (50/2 + 7 = 32) would be considered creepy. As the graph shows, there is a lower limit and an upper limit. The lower limit can be defined as f(x) = x /2 + 7 in which x is your age and f(x) is the minimum age of your partner. The upper limit can be defined as f^-1(x) = 2( x − 7) in which x is your age and f^-1(x) is the maximum age of your partner. As age increases, the age range of potential non-creepy partners widens. At 26, the range of non-creepy partners is 18 years (20- to 38-year-olds). At 50, it is 54 years (32 to 86 years old). At age 14, you can only date people your own age. The same also works with infinity, but even Methuselah died once. While the application of this rule actually reduces the number of potential matches further, Cueball presents it in a positive way by showing that there are whole swathes of people who she couldn't marry in the first place without being in a creepy relationship. But, as her age increases, the range of non-creepy partners also increases. Combined with Census Bureau data for how many people exist within any such range, Cueball shows that her eligible dating pool is in fact still increasing. Megan notes that graph-making nerds like Cueball may have a hard time finding dates, but this is refuted by the title text. [Megan is sitting on the ground with her elbows on her knees and her hands on her chin.] Megan: This sucks. The median first marriage age is 26. The pool of singles is shrinking. I'm running out of time. Cueball: Actually, not quite. Cueball: Yes, older singles are rarer. But as you get older, the dateable age range gets wider. An 18-year-old's range is 16–22, whereas a 30-year-old's might be more like 22–46. Text on chart: Standard creepiness rule: Don't date under (Age/2 + 7) Cueball: I did some analysis of this with the Census Bureau numbers just last weekend. Your dating pool actually grows until middle age. So don't fret so much! [The first chart is labeled "Singles" and is a decreasing graph. The second graph is labeled Dating Pool, and is a bell curve.] Megan: Did your analysis say anything about the dating prospects of people who spend weekends at home making graphs? Cueball: Come on. Somewhere at the edge of the bell curve is the girl for me.

Braille

Braille

https://www.xkcd.com/315

https://www.explainxkcd.com/wiki/index.php/315:_Braille

I learned to read braille a while back, and I've noticed that the messages on signs don't always match the regular text. [A sign reads "Third Floor Office" with braille print underneath. Cueball is reading the braille.] Cueball (thinking): s-i-g-h-t-e-d-p-e-o-p-l-e-s-u-c-k ... Hey!

Braille is a writing system for the blind and visually impaired using bumps on a paper, slate, etc. However, since most sighted people have no need for braille, and because braille messages may need to convey purely-visual information to blind people, the braille message may be adjusted from the original message. In this case, however, it acts as a jab toward people who are not blind, saying that "sighted people suck," which is obviously not something you would typically see (no pun intended) [ citation needed ] on informational signs. [ SIGHTation needed ] Similar "translations" can be found when one deciphers the alien translations on nearly all signs in Futurama. The title text shows a practical (and more realistic) example of where regular text and braille text may differ. As the visually impaired cannot see color, the label would need to identify some other defining feature of the button in question, such as the given measurement. I learned to read braille a while back, and I've noticed that the messages on signs don't always match the regular text. [A sign reads "Third Floor Office" with braille print underneath. Cueball is reading the braille.] Cueball (thinking): s-i-g-h-t-e-d-p-e-o-p-l-e-s-u-c-k ... Hey!

Loud Sex

Loud Sex

https://www.xkcd.com/316

https://www.explainxkcd.com/wiki/index.php/316:_Loud_Sex

My neighbor has loud sex. [Cueball in bed, covering his head with a pillow. There is sound coming from outside.] OHHHHH GASP AAAAAAA Good for her and all, but it keeps me up at night. And she's so smug about it. [Cueball and neighbor coming out of their apartments.] Neighbor: Sorry, could you hear us last night? Oh, you know how it gets sometimes. Cueball: Not really... But tonight I finally get my revenge. Because now I have a loud girlfriend too. [Megan with "LOUD" and an arrow pointing to her.] And an elliptical reflector dish. [Diagram of an elliptical reflector dish.] [Cueball and Megan having sex, with the dish behind them reflecting the sex sound effects, in a way that they focus, through walls, on his neighbor sitting up in bed while holding her head in pain.]

Cueball 's neighbor likes to engage in loud sex, which keeps Cueball awake at night, and she pretends to apologize for it as a way of bragging, so Cueball wants to get revenge. A simple way would be to inflict the same to her in retaliation by having loud sex when she is not. But Cueball adds a science nerd's touch to it, with an elliptical reflector dish. As shown on the schema, such a dish reflects the sound waves in a way that all waves originating from a specific point (the first focus of the ellipse the dish's shape is based on) converge after reflection to a specific other point (the second focus of the same ellipse). [1] Cueball calibrates and installs his elliptical dish in such a way that all the sound coming from his loud girlfriend's head during sex is concentrated after reflection to his neighbor's head in her bed. This makes his loud sex far louder to her than hers was to him. The title text makes a double entendre , where a spherical or parabolic reflector would cause different behaviors for the sound waves, but the play on words leads the reader to believe that aberrant sexual behavior would occur. [1]: Note: that is actually the behaviour of an ellipsoidal reflector dish, or an elliptic one in two dimensions; but in 3D an elliptic one works similarly, only converging waves from a line to another line, instead of points. My neighbor has loud sex. [Cueball in bed, covering his head with a pillow. There is sound coming from outside.] OHHHHH GASP AAAAAAA Good for her and all, but it keeps me up at night. And she's so smug about it. [Cueball and neighbor coming out of their apartments.] Neighbor: Sorry, could you hear us last night? Oh, you know how it gets sometimes. Cueball: Not really... But tonight I finally get my revenge. Because now I have a loud girlfriend too. [Megan with "LOUD" and an arrow pointing to her.] And an elliptical reflector dish. [Diagram of an elliptical reflector dish.] [Cueball and Megan having sex, with the dish behind them reflecting the sex sound effects, in a way that they focus, through walls, on his neighbor sitting up in bed while holding her head in pain.]

That Lovin' Feelin'

That Lovin' Feelin'

https://www.xkcd.com/317

https://www.explainxkcd.com/wiki/index.php/317:_That_Lovin%27_Feelin%27

Cueball: You never close your eyes anymore when I kiss your lips Cueball: And there's no tenderness like before in your fingertips. [Cueball thoughtfully places his hand on his chin.] Cueball: Maybe I should try your sister instead.

This is a parody of the popular song by The Righteous Brothers , " You've Lost That Lovin' Feelin' ." The singer is talking about the cooling of his relationship with his significant other, and how the joy of their romance has been missing lately, and asks what they have to do to get it back. The actual first verse and chorus are as follows: You never close your eyes anymore when I kiss your lips And there's no tenderness like before in your fingertips You're trying hard not to show it (baby) But baby, baby, I know it: You've lost that lovin' feelin' Ohh, that lovin' feelin' You've lost that lovin' feelin', Now it's gone, gone, gone, ohh-ohh. In this comic's parody of the song, Cueball decides that since his relationship with his current girlfriend is cooling, maybe he should try her sister instead. (And as mentioned in the title text, at least she will have sex with him). Cueball: You never close your eyes anymore when I kiss your lips Cueball: And there's no tenderness like before in your fingertips. [Cueball thoughtfully places his hand on his chin.] Cueball: Maybe I should try your sister instead.

Nostalgia

Nostalgia

https://www.xkcd.com/318

https://www.explainxkcd.com/wiki/index.php/318:_Nostalgia

[Cueball and Megan, both wearing headsets with antennae, sunglasses, and jetpacks, are hovering.] Cueball: Darling, let's put on our best fake accounts, connect to the core ForumSpace, and trick people into looking at a picture of a man's distended anus! Megan: Oh, it'll be just like old times!

Cueball and Megan refer to the practice of tricking people to see shock sites using bait-and-switch pranks. A shock site is a website that is intended to be offensive, disgusting, and/or disturbing to its viewers, containing materials of high shock value that is also considered distasteful and crude, and is generally of a pornographic, scatological, extremely violent, insulting, painful, profane, or otherwise provocative nature. This comic is a direct reference to the former shock site goatse.cx that displayed a human distended anus (among other things). The domain was taken down in 2004, but it remains a memorable cultural reference from its time period. It therefore may be cited as nostalgia by trolls in the future. This comic evidently takes place in the future, as the characters are using some sort of advanced levitation technology that has yet to exist. The title text warns us not to Google this meme, as it contains some horrifying results. If you ignore the warning from the title text and Google for "distended anus," you will find many results on this awful dysfunction like rectal prolapse . Furthermore, the aforementioned shock site still exists at [REDACTED]. [Cueball and Megan, both wearing headsets with antennae, sunglasses, and jetpacks, are hovering.] Cueball: Darling, let's put on our best fake accounts, connect to the core ForumSpace, and trick people into looking at a picture of a man's distended anus! Megan: Oh, it'll be just like old times!

Engineering Hubris

Engineering Hubris

https://www.xkcd.com/319

https://www.explainxkcd.com/wiki/index.php/319:_Engineering_Hubris

[Landscape in the background, canyon with a winding road.] Maybe engineering is the pursuit of an unattainable perfection. Maybe it's impossible to create something bug-free. Maybe I'm a fool Maybe the tyranny of Murphy is the penalty for hubris. But I just can't shake the feeling [Cueball standing on boxes labeled "ACME."] With all those supplies I could have caught that roadrunner.

This comic starts with a philosophical musing about engineering . The last panel reveals a joke about Wile E. Coyote and The Road Runner , a cartoon series created by Chuck Jones . In the cartoon, the Coyote is constantly building odd contraptions (with parts ordered from the Acme Corporation ) to catch the Road Runner. The Coyote never succeeds, often because his devices don't work as intended. The word Hubris from the comic title means extreme pride or arrogance. It is a theme from the classic Greek plays, and is usually severely punished by the gods. The title text is implying that Chuck Jones would not let hubris go unpunished; the engineer might be able to construct 'better' traps than Wile E, but they would still be doomed to fail. From the second panel, Murphy's Law can be simplified to "Anything that can go wrong will go wrong." It was originally developed as a guideline for accident prevention starting at the design level. In the common vernacular today, it is interpreted more liberally: "If there is even the slightest chance of an unfortunate accident occurring, despite all your attempts to prevent it, the accident will happen anyway, purely out of spite." The namesake Edward A. Murphy Jr. has since evolved to mythic proportions, being cast as a vengeful god of misfortune and ruin. [Landscape in the background, canyon with a winding road.] Maybe engineering is the pursuit of an unattainable perfection. Maybe it's impossible to create something bug-free. Maybe I'm a fool Maybe the tyranny of Murphy is the penalty for hubris. But I just can't shake the feeling [Cueball standing on boxes labeled "ACME."] With all those supplies I could have caught that roadrunner.

28-Hour Day

28-Hour Day

https://www.xkcd.com/320

https://www.explainxkcd.com/wiki/index.php/320:_28-Hour_Day

[Above the panels of the main comic, there is a ruler-like time line diagram that shows the hours in a week. It has 6 black sections labeled "bed" in white text, at the top and 7 black sections labeled "night" in white text, at the bottom (the first and last sections are split in two as it goes from the end of the week to the start of the (next) week. So there are 8 night sections, but they only cover 7 times 12 hours). The night sections always go from 6PM to 6AM. But the bed sections are only 8 hours long and they only stay fully over the night sections two times, and two times they are not above the night sections at all. Above the ruler, the bed times are shown. These labels are over the relevant ticks on the ruler. The ruler has small ticks for every two hours, longer ticks at noon, and a line that goes all the way through the ruler dividing each day. The ruler begins on midnight as Sunday starts and ends as Saturday finishes at midnight. Below the ruler each day are labels with the three-letter abbreviations in a much larger font. Here below the rulers, text is transcribed with the day first, then night or bed according to which comes first, and the time interval for bed given after each bed. The first and last night will only be a partial word and only the first time will there be a (ni)ght to start.] Sun ght Bed 10AM 6PM Night Mon Bed 2PM 10PM Night Tue Bed 6PM 2AM Night Wed Night Bed 10PM 6AM Thu Night Fri Bed 2AM 10AM Night Sat Bed 6AM 2PM Nig [Below the ruler are five panels. In the first, two Cueball-like guys are talking together. Cueball is addressing his friend with one hand raised.] Cueball: You have trouble sleeping right? Friend: Only when your mom is over. [Cueball is now standing next to a an easel with a large version of the chart shown above the panels. Cueball is pointing to the chart while his friend is looking at it.] Cueball: Since your work is flexible- Friend: -Like your mom- Cueball: -you should try the 28-hour day - 20 awake, 8 asleep (or 19/9 if you prefer). Friend: I prefer your mom. [Cueball moves forward toward his friend, with the chart behind him. He holds both hands, held together, up in front of him. The easel with the chart can now be seen to have three legs, as opposed to only two shown in the previous panel.] Cueball: It synchs up with the week - you spend weekdays awake normally, then on weekends you can go out all night. Friend: Just like your mom. [In a frameless panel, only Cueball is shown from the torso up. He gestures with both arms raised on each side of him.] Cueball: It means four extra hours daily. You can stay up until you're exhausted every day and then spend a full 9 hours asleep each night! [Back to both again, but without the chart. Cueball leans toward his friend as his friend lifts a hand to his chin.] Friend: But how much time can I spend doing your mom? Cueball: You? I'm guessing three or four minutes, tops. Friend: ...Well played.

The 28-Hour Day is a modified sleep schedule proposed to accommodate the discrepancy between the earth's day-night cycle and certain people's preferred sleep schedules. It discards the traditional notion of sleeping at night and replaces it with sleeping when it is more convenient for weekend parties and mid-week insomnia. It is also the only reasonable and consistent alternative day length that will sync with the widely accepted and practiced 168-hour week (168 = 7×24 = 6×28), with the arguable exception of eight 21-hour days. Underneath the weekly timeline, Cueball describes the schedule's selling points to his friend, who apparently has difficulty sleeping. Cueball's friend shows little interest in this idea, and instead he resorts to low-quality "your mom" jokes. Cueball merely bides his time, and in the end successfully trumps the jokes with a response that impugns his friend's sexual stamina, leading him to concede defeat. The title-text uses " Small print " to mean "Disclaimer" and relieves the idea's creator of any responsibility in the case that it is tried and the tester finds the schedule to be a really bad idea. As he states, if you live by this schedule, chances are you will be driven stark raving mad. Given that Cueball gives his friend with the bad mom jokes this advice, it could be another way to try to punish him for the jokes. Although Randall makes several Your Mom comics , he has also in some comics shown that he dislikes these kind of jokes, especially when used too much in real life (see 366: Your Mom .) [Above the panels of the main comic, there is a ruler-like time line diagram that shows the hours in a week. It has 6 black sections labeled "bed" in white text, at the top and 7 black sections labeled "night" in white text, at the bottom (the first and last sections are split in two as it goes from the end of the week to the start of the (next) week. So there are 8 night sections, but they only cover 7 times 12 hours). The night sections always go from 6PM to 6AM. But the bed sections are only 8 hours long and they only stay fully over the night sections two times, and two times they are not above the night sections at all. Above the ruler, the bed times are shown. These labels are over the relevant ticks on the ruler. The ruler has small ticks for every two hours, longer ticks at noon, and a line that goes all the way through the ruler dividing each day. The ruler begins on midnight as Sunday starts and ends as Saturday finishes at midnight. Below the ruler each day are labels with the three-letter abbreviations in a much larger font. Here below the rulers, text is transcribed with the day first, then night or bed according to which comes first, and the time interval for bed given after each bed. The first and last night will only be a partial word and only the first time will there be a (ni)ght to start.] Sun ght Bed 10AM 6PM Night Mon Bed 2PM 10PM Night Tue Bed 6PM 2AM Night Wed Night Bed 10PM 6AM Thu Night Fri Bed 2AM 10AM Night Sat Bed 6AM 2PM Nig [Below the ruler are five panels. In the first, two Cueball-like guys are talking together. Cueball is addressing his friend with one hand raised.] Cueball: You have trouble sleeping right? Friend: Only when your mom is over. [Cueball is now standing next to a an easel with a large version of the chart shown above the panels. Cueball is pointing to the chart while his friend is looking at it.] Cueball: Since your work is flexible- Friend: -Like your mom- Cueball: -you should try the 28-hour day - 20 awake, 8 asleep (or 19/9 if you prefer). Friend: I prefer your mom. [Cueball moves forward toward his friend, with the chart behind him. He holds both hands, held together, up in front of him. The easel with the chart can now be seen to have three legs, as opposed to only two shown in the previous panel.] Cueball: It synchs up with the week - you spend weekdays awake normally, then on weekends you can go out all night. Friend: Just like your mom. [In a frameless panel, only Cueball is shown from the torso up. He gestures with both arms raised on each side of him.] Cueball: It means four extra hours daily. You can stay up until you're exhausted every day and then spend a full 9 hours asleep each night! [Back to both again, but without the chart. Cueball leans toward his friend as his friend lifts a hand to his chin.] Friend: But how much time can I spend doing your mom? Cueball: You? I'm guessing three or four minutes, tops. Friend: ...Well played.

Thighs

Thighs

https://www.xkcd.com/321

https://www.explainxkcd.com/wiki/index.php/321:_Thighs

[Cueball is singing into a microphone he is holding while Megan sit in her office chair typing on her computer. Musical notes fly around Cueball.] Cueball: It's the thigh of the tiger [Cueball continues to sing, titling his head upwards.] Cueball: When the moon hits your thigh like a big pizza pie, that's amore. [Cueball sings on now holding the microphone in both hands.] Cueball: She's my brown-thighed girl. Megan: Don't you have a job or something? Megan: Also, Eww.

In each panel, Cueball sings a verse from a different song where he replaces the word "eye" with the word "thigh." First it is Survivor's " Eye of the Tiger ," then Dean Martin's " That's Amore ," and finally Van Morrison's " Brown Eyed Girl ." The comic shows how vastly different each song's meaning becomes when "eye" is replaced with "thigh." In the last panel, Cueball's version makes Megan go "eww," and she asks him if he doesn't have a job he should be doing instead. The eww refers to the fact that the brown-eyed girl turns into a brown-thighed girl, and such colored thighs could be eminently possible via an act of poor defecation on oneself, hence the disgust reaction from Megan. In the title text, it seems that Cueball continues with a reference to the first line of The Battle Hymn of the Republic , adding to the humorous effect, since typically thighs cannot see. But mainly it is a sexual joke playing on the double meaning of " coming ". In 1814: Color Pattern , Randall makes his own version of "That's Amore," this time letting Megan sing it to Cueball. [Cueball is singing into a microphone he is holding while Megan sit in her office chair typing on her computer. Musical notes fly around Cueball.] Cueball: It's the thigh of the tiger [Cueball continues to sing, titling his head upwards.] Cueball: When the moon hits your thigh like a big pizza pie, that's amore. [Cueball sings on now holding the microphone in both hands.] Cueball: She's my brown-thighed girl. Megan: Don't you have a job or something? Megan: Also, Eww.

Pix Plz

Pix Plz

https://www.xkcd.com/322

https://www.explainxkcd.com/wiki/index.php/322:_Pix_Plz

[Black Hat stands in the entrance to a room. The door has been broken down. A surprised Cueball has turned away from his computer to face the remains of the door.] Black Hat: Hi. I'm here about the girl who visited your IRC channel last night looking for Java help. Cueball: What did you do to my door? Black Hat: When someone with a feminine username joins your community and you say "OMG a woman on the Internet" and 'jokingly' ask for naked pics, you are being an asshole. You are not being ironic. You are not cracking everybody up. You are the number one reason women are so rare on the Internet. Black Hat: At least, the parts of it you frequent. [Joanna enters the room, holding some sort of device.] Black Hat: As someone who likes nerdy girls, I do not appreciate this. I'm here to ban you from the Internet. The gal behind me with the EMP cannon is Joanna - she'll be assigned to you for the next year. Try to go online and she'll melt your PC. Cueball: Dude, she's hot. Is she single? Black Hat: Joanna, fire.

Though this comic predates it, there is an Internet meme best stated as "there are no girls on the Internet." It is also known as Rule 16 or Rule 30 of the Internet , not to be confused with Wolfram's cellular automata . This comes partly from a supposition that girls aren't smart enough to go on the Internet or even use technology, and more directly from the idea that they are afraid of interacting in such a male-dominated subculture, so anyone claiming to be female on the Internet must be a male pretending to be one for the purposes of active or passive trolling. Thankfully for humanity at large, the meme is now the opposite of true (just look at the female-dominated Facebook), but still lives on as a joke, albeit not always a pleasant one. For many users, the puerile nature of the Internet creates a repulsive force because of exactly what Cueball is doing. As soon as anyone claims to be a female online, there will invariably be a slew of " tits or gtfo " replies. Randall projects this stereotypical Internet douchebaggery onto Cueball , who behaves this way out of misogyny thinly disguised as a joke. This barely-a-joke, found in certain areas of the Internet (especially IRC and 4chan), holds the view that women are only "good for" sex and porn. By making such a huge deal out of her being a girl, he directs unwanted sexual attention at any female who joins. Black Hat , while usually a destructive force and self-proclaimed classhole , here switches positions with Cueball, standing up for women everywhere. (This makes sense when you consider that Black Hat tends to pursue Randall's thoughts in a more controversial way, see 86: Digital Rights Management ). However, he still keeps some of his destructive tendencies and knocks down Cueball's door. He enlists the help of a Ponytail character named Joanna to ban Cueball from the Internet. (More than 9 years later, Joanna is hired to help Hillary Clinton win the 2016 United States presidential election in 1756: I'm With Her , released the day before that election. She is also shown in the 1000: 1000 Comics , where she is seen at number 653 .) IRC is the acronym for Internet Relay Chat. It is a protocol that eventually evolved into the instant messengers , chat rooms , and XMPP (formerly Jabber) servers around today. With the advent of live-streaming video online, IRC channels are making a come-back as a way for hosts and audiences to communicate with each other in real-time. An EMP is an electromagnetic pulse that will disrupt electronics from functioning normally. An EMP is a short burst of electromagnetic energy. Small EMPs will disrupt electricity momentarily, while larger EMPs are capable of burning out circuitry and erasing hard drives. At the title text, Cueball tries to defend his misogyny by claiming that one of his IRC chat system acquaintances is a female, as if to imply that that makes his words no longer misogynist (this is similar to the defense "I'm not racist! Some of my best friends are black!"). [Black Hat stands in the entrance to a room. The door has been broken down. A surprised Cueball has turned away from his computer to face the remains of the door.] Black Hat: Hi. I'm here about the girl who visited your IRC channel last night looking for Java help. Cueball: What did you do to my door? Black Hat: When someone with a feminine username joins your community and you say "OMG a woman on the Internet" and 'jokingly' ask for naked pics, you are being an asshole. You are not being ironic. You are not cracking everybody up. You are the number one reason women are so rare on the Internet. Black Hat: At least, the parts of it you frequent. [Joanna enters the room, holding some sort of device.] Black Hat: As someone who likes nerdy girls, I do not appreciate this. I'm here to ban you from the Internet. The gal behind me with the EMP cannon is Joanna - she'll be assigned to you for the next year. Try to go online and she'll melt your PC. Cueball: Dude, she's hot. Is she single? Black Hat: Joanna, fire.

Ballmer Peak

Ballmer Peak

https://www.xkcd.com/323

https://www.explainxkcd.com/wiki/index.php/323:_Ballmer_Peak

[A graph with "programming skill" on the Y-axis and "blood alcohol concentration" on the X-axis. The Y-axis slowly goes down, but spikes at 0.1337%.] [Cueball is making a presentation with the graph.] Cueball: Called the Ballmer Peak, it was discovered by Microsoft in the 80's. The cause is unknown but somehow a B.A.C between 0.129% and 0.138% confers superhuman programming ability. Cueball: However, it's a delicate effect requiring careful calibration – you can't just give a team of coders a year's supply of whiskey and tell them to get cracking. Spectator: ...Has that ever happened? Cueball: Remember Windows ME? Spectator: I knew it! In the above-mentioned speech at Google, Randall Munroe explained that he tried to experiment on himself about the relationship between alcohol intoxication and intellectual skills, by solving a Rubik's Cube repeatedly while getting more and more drunk. He eventually found that he could get deeply drunk without degrading very much his performance at solving the puzzle (contrary to, for instance, finding and picking up the Cube which became something of a problem towards the end). He suggested that the Rubik's Cube wasn't a good test to study this relationship, the cube probably being solved with muscle memory rather than real intellectual skills.

This comic is about alcohol and programming ability. Programmers sometimes have a reputation for drinking habits, and programmer gatherings (such as hackfests ) tend to offer copious amounts of alcohol. More generally, intoxicated programmers can get the impression that , by being a little disconnected from physical reality, they become more efficient at their programming. The comic is a take on this belief, with two references: The curve in the comic suggests that, while generally decreasing with alcohol intoxication, at just the right level, the skill of a programmer gets terrific indeed. Randall named the peak after Steve Ballmer, as if discovered by him; this references the analogously named Balmer peaks (with one 'L'), and the idea that Steve Ballmer makes for an easy association of programming and alcohol. The peak of the curve occurs at a BAC of 0.1337%, which is a reference to leet . (See this interview with Randall ). The end of the comic turns the whole idea into a sideways jab at Windows ME , a version of Microsoft Windows often criticized for being buggy, slow, and unstable: it suggests that ME was developed by programmers completely drunk, because their managers wanted to exploit this "Ballmer peak," but did so without any precaution. That idea fit the result of a buggy and unstable product well. On the contrary, the title text claims that Apple uses this effect with careful calibration, by delivering precise quantities of alcohol ( schnapps ) to its programmers via intravenous therapy (IV). An actual research paper published in March 2012 showed that the situation described in this comic is not far from reality. Researchers found that intoxicated participants performed better than sober participants on a test that evaluates creative problem solving skills, and were also more likely to evaluate their own solutions as insightful. However, the study only tested a B.A.C. of 0.075%, not between 0.129% and 0.138% as displayed in the comic. [A graph with "programming skill" on the Y-axis and "blood alcohol concentration" on the X-axis. The Y-axis slowly goes down, but spikes at 0.1337%.] [Cueball is making a presentation with the graph.] Cueball: Called the Ballmer Peak, it was discovered by Microsoft in the 80's. The cause is unknown but somehow a B.A.C between 0.129% and 0.138% confers superhuman programming ability. Cueball: However, it's a delicate effect requiring careful calibration – you can't just give a team of coders a year's supply of whiskey and tell them to get cracking. Spectator: ...Has that ever happened? Cueball: Remember Windows ME? Spectator: I knew it! In the above-mentioned speech at Google, Randall Munroe explained that he tried to experiment on himself about the relationship between alcohol intoxication and intellectual skills, by solving a Rubik's Cube repeatedly while getting more and more drunk. He eventually found that he could get deeply drunk without degrading very much his performance at solving the puzzle (contrary to, for instance, finding and picking up the Cube which became something of a problem towards the end). He suggested that the Rubik's Cube wasn't a good test to study this relationship, the cube probably being solved with muscle memory rather than real intellectual skills.

Tapping

Tapping

https://www.xkcd.com/324

https://www.explainxkcd.com/wiki/index.php/324:_Tapping

[Cueball is sitting at a desk, tapping various parts of it.] Cueball: Hey, I can get different pitches by tapping on different parts of the desk. Tap Tap Tap Tap [Cueball starts tapping faster, with both hands.] Cueball: Sweet, I can do the Jurassic park theme! Tap Tap Tap Tap Tap Tap Tap [Cueball tap the desk very rapidly, legs crossed.] Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap [Later, elsewhere.] Megan: So, what did you do all afternoon? Cueball: Hung out.

In the first panel, Cueball makes the chance observation that tapping different points on a desk's surface results in different pitches being produced, a consequence of the desk's different resonant frequencies at these points. He soon learns that by using the pitches produced, he can replicate the well-known theme music to the film Jurassic Park . The third panel depicts that, given a lack of other entertaining stimuli, Cueball soon becomes engrossed in his newly discovered musical instrument, and his music grows in complexity. This is a fun observation about part of human nature, to which many people can relate. Sadly, Cueball doesn't feel like telling Megan what he did, and instead, he just gives her an empty answer. Cueball perhaps feels, as Randall suggests in the title text, that he could not explain why the tapping activity was fun in its own right and not just a consequence of boredom, so he avoids having to explain in the first instance. Other comics have shown the idea of feeling embarrassed by what one likes, to the point of refusing to admit that one likes it. Examples are 245: Floor Tiles and the title text of 1103: Nine . [Cueball is sitting at a desk, tapping various parts of it.] Cueball: Hey, I can get different pitches by tapping on different parts of the desk. Tap Tap Tap Tap [Cueball starts tapping faster, with both hands.] Cueball: Sweet, I can do the Jurassic park theme! Tap Tap Tap Tap Tap Tap Tap [Cueball tap the desk very rapidly, legs crossed.] Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap Tap [Later, elsewhere.] Megan: So, what did you do all afternoon? Cueball: Hung out.

A-Minus-Minus

A-Minus-Minus

https://www.xkcd.com/325

https://www.explainxkcd.com/wiki/index.php/325:_A-Minus-Minus

[Black Hat is packing a bobcat into a box; Megan stands beside him.] Megan: What are you doing? Black Hat: Making the world a weirder place. Bobcat: mrrowlll [Black Hat has finished taping the package for shipping.] Black Hat: Starting with my eBay feedback page. [Bandaged person at a computer with assorted debris around the floor.] Screen: comments: Bandaged person typing: Instead of office chair package contained bobcat. Bandaged person typing: Would not buy again.

Black Hat is trying to make the world a weirder place by shipping bobcats to his eBay buyers. Ordinarily, negative feedback is used to warn future buyers about sellers who ship broken products or post misleading listings. In this case, the unfortunate buyer is leaving feedback warning future buyers that Black Hat ships bobcats instead of the actual products, though "would not buy again" seems to be a rather feeble response to the replacement. This appears to have been a continuing project, as Cueball receives random packages a year and a half later ( 576: Packages ). Four years later, it is shown that you can blackmail Black Hat into not sending you a bobcat ( 837: Coupon Code ). This comic is also referenced in a popular Amazon review for Randall Munroe's book, What If: Serious Scientific Answers to Absurd Hypothetical Questions. The weak "would not buy again" comment is a play on the stock "would buy again" comment often found in positive eBay feedback; the title "A-Minus-Minus" is a play on the frequent comment "A++." That in turn, sometimes with varying numbers of pluses, seems to be an easy way people use to pad the end of an eBay comment field to the maximum 80 characters. It's also a reference to jokes in which exceptionally good schoolwork is graded with extra pluses after an A+ (and exceptionally bad work is graded with large numbers of minuses after an F). The title text is about a flaw in eBay's feedback system: You can intentionally do nasty things to your buyers and get very bad reviews, but still have overall high feedback scores as long as you don't do it too often. (See also 937: TornadoGuard , which shows a different flaw in the concept of averaging reviews — namely that five-star reviews for aesthetic qualities are weighted equally to one-star reviews for major functional deficits — and 1098: Star Ratings , which addresses the topic as well.) These reviews would be disregarded by future customers as well for their weirdness. [Black Hat is packing a bobcat into a box; Megan stands beside him.] Megan: What are you doing? Black Hat: Making the world a weirder place. Bobcat: mrrowlll [Black Hat has finished taping the package for shipping.] Black Hat: Starting with my eBay feedback page. [Bandaged person at a computer with assorted debris around the floor.] Screen: comments: Bandaged person typing: Instead of office chair package contained bobcat. Bandaged person typing: Would not buy again.

Effect an Effect

Effect an Effect

https://www.xkcd.com/326

https://www.explainxkcd.com/wiki/index.php/326:_Effect_an_Effect

My Hobby: Using the more obscure meanings of "affect" and "effect" to try to trip up amateur grammar Nazis. Cueball: I think that our foreign policy effects the situation. Computer: You mean "affects." Cueball: tee hee hee

"Affect" and "effect" can each both be a noun and a verb, share the sense of influence , and they are often confused with each other. (See the usage note under "Affect.") In careful speech, both words (as verbs) are similar but not identical. "Affect" is /əˈfɛkt/ (or uh- fekt ) and "effect" is /ɪˈfɛkt/ (or ih- fekt ). However, for some people, these words are homophones — it's also explained here: homophones affect vs effect . "Effect" is usually a noun, meaning a result , and "affect" usually a verb, meaning to act upon . "Effect" as a verb has the slightly different meaning to bring about . Cueball says that the foreign policy causes the situation, not, as the "grammar nazi" thinks, that it changes the situation. The title of the comic translates to cause or bring about a result , which is just what Cueball does! It can also be seen as a play on words, being similar to the phrase "cause and effect." The title text refers to the Victory marking practice common among fighter pilots in a war zone. Fighter pilots who score a "kill" on an opposing aircraft will have a silhouette of the downed plane painted on the side of their plane as a way of keeping track of kills. In this sense, Cueball "shot down," figuratively speaking, an online (grammar) nazi, and would mark it by painting a silhouette on the side of his computer. See also 1429: Data . My Hobby: Using the more obscure meanings of "affect" and "effect" to try to trip up amateur grammar Nazis. Cueball: I think that our foreign policy effects the situation. Computer: You mean "affects." Cueball: tee hee hee

Exploits of a Mom

Exploits of a Mom

https://www.xkcd.com/327

https://www.explainxkcd.com/wiki/index.php/327:_Exploits_of_a_Mom

[Mrs. Roberts receives a call from her son's school on her wireless phone. She is standing with a cup of hot coffee or tea (shown with a small line above the cup) facing a small round three-legged table to the right. The voice of the caller is indicated to come from the phone with a zigzag line.] Voice over the phone: Hi, This is your son's school. We're having some computer trouble. [In this frame-less panel Mrs. Roberts has put the cup down on the table turned facing out.] Mrs. Roberts: Oh, dear – did he break something? Voice over the phone: In a way – [Mrs. Roberts is now drinking from the cup again looking right. The table is not shown.] Voice over the phone: Did you really name your son Robert'); DROP TABLE Students;-- ? Mrs. Roberts: Oh, yes. Little Bobby Tables, we call him. [Mrs. Roberts holds the cup down.] Voice over the phone: Well, we've lost this year's student records. I hope you're happy. Mrs. Roberts: And I hope you've learned to sanitize your database inputs. This comic has become rather famous, spawning a site at http://bobby-tables.com about preventing SQL injection and also at the official Python SQLite documentation . Noted security expert Bruce Schneier (who often quotes xkcd) mentioned a similar attack that happened in the 2010 Swedish general elections, and several people tried it on Randall's color survey . In 1253: Exoplanet Names , someone (presumably Mrs. Roberts) attempts to perform a similar trick, submitting the name e'); DROP TABLE PLANETS;-- to the IAU. It is later revealed in 342: 1337: Part 2 that the daughter's middle name is Elaine (full name: Help I'm trapped in a driver's license factory Elaine Roberts ). This is thus the first time Elaine is mentioned. This comic was, presumably, a setup for the " 1337 " series where both of the hacker mom's kids are shown for the first time. This comic is available as a signed print in the xkcd store . In 2020 this happened in real life: Company made to change name that could be used for website hacks .

Mrs. Roberts receives a call from her son 's school. The caller, likely one of the school's administrators, asks if she really named her son Robert'); DROP TABLE Students;-- , a rather unusual name. Perhaps surprisingly, Mrs. Roberts responds in the affirmative, claiming that she uses the nickname "Little Bobby Tables." As the full name is read into the school's system's databases without data sanitization , it causes the "Students" table in the database to be dropped, meaning it gets deleted. The title of this comic is a pun. Exploit can mean an accomplishment or heroic deed, but in computer science, the term refers to a program or technique that takes advantage of a vulnerability in other software. In fact, one could say that her exploit is to exploit an exploit (her achievement is to make use of a vulnerability). The title can also refer to her choice of name for her son, which is rather extraordinary. In SQL , a database programming language, commands are separated by semicolons ; , and strings of text are often delimited using single quotes ' . Parts of commands may also be enclosed in parentheses ( and ) . Data entries are stored as "rows" within named "tables" of similar items (e.g., Students ). The command to delete an entire table (and thus every row of data in that table) is DROP TABLE , as in DROP TABLE Students; . The exploited vulnerability here is that the single quote in the name input was not correctly "escaped" by the software. That is, if a student's name did indeed contain a quote mark, it should have been read as one of the characters making up the text string and not as the marker to close the string, which it erroneously was. Lack of careful parsing is a common SQL vulnerability; this type of exploit is referred to as SQL injection . Mrs. Roberts thus reminds the school to make sure that they have added data filtering code to prevent code injection exploits in the future. For example, to add information about Elaine to a data table called 'Students', the SQL query could be: INSERT INTO Students (firstname) VALUES ('Elaine'); However, using the odd name Robert');DROP TABLE Students;-- where we used "Elaine" above, the SQL query becomes: INSERT INTO Students (firstname) VALUES ('Robert');DROP TABLE Students;-- '); By insertion of the two semi-colons in the odd name, this is now three well-formed SQL commands: INSERT INTO Students (firstname) VALUES ('Robert'); DROP TABLE Students; -- '); The first line is valid SQL code that will legitimately insert data about a student named Robert. The second line is valid injected SQL code that will delete the whole Student data table from the database. The third line is a valid code comment ( -- denotes a comment), which will cause the rest of the line to be ignored by the SQL server. For this to work, it helps to know the structure of the database. But it's quite a good guess that a school's student management database might have a table named Students . Of course, in real life, most exploits of this kind would be performed not by engineering a person's name such that it would eventually be entered into a school database query, but rather by accessing some kind of input system (such as a website's login screen or search interface) and guessing various combinations by trial and error until something works, perhaps by first trying to inject the SHOW TABLES; command to see how the database is structured. To correctly and harmlessly include the odd name in the Students table in the school database the correct SQL is: INSERT INTO Students (firstname) VALUES ('Robert'');DROP TABLE Students;-- '); Note that the single quote after Robert is now sanitized by doubling it, which changes it from malicious code to harmless data, and the full first 'name' of the student Robert';DROP TABLE Students;-- is now stored correctly. It should be noted that while data sanitization can mitigate the risks of SQL injection, the proper prevention technique is to use Prepared statements . Noting the difference between the "actual" name using the word TABLE and the child's nickname being Bobby Tables, one could argue that there's an implied reference to one of the most argued topics of database naming conventions - should table names be singular or plural. The title text references that Mrs. Roberts' daughter is named "Help I'm trapped in a driver's license factory". This is a play on how if someone is stuck and forced to work in a manufacturing factory/plant, then they will write on the product "Help I am trapped in a ____ factory" in order to tell people on the outside. Having this name would cause any police officer who pulls her over to show some concern. And getting the license in the first place would likely be difficult. The idea of inserting a help message like this was already used in 10: Pi Equals . [Mrs. Roberts receives a call from her son's school on her wireless phone. She is standing with a cup of hot coffee or tea (shown with a small line above the cup) facing a small round three-legged table to the right. The voice of the caller is indicated to come from the phone with a zigzag line.] Voice over the phone: Hi, This is your son's school. We're having some computer trouble. [In this frame-less panel Mrs. Roberts has put the cup down on the table turned facing out.] Mrs. Roberts: Oh, dear – did he break something? Voice over the phone: In a way – [Mrs. Roberts is now drinking from the cup again looking right. The table is not shown.] Voice over the phone: Did you really name your son Robert'); DROP TABLE Students;-- ? Mrs. Roberts: Oh, yes. Little Bobby Tables, we call him. [Mrs. Roberts holds the cup down.] Voice over the phone: Well, we've lost this year's student records. I hope you're happy. Mrs. Roberts: And I hope you've learned to sanitize your database inputs. This comic has become rather famous, spawning a site at http://bobby-tables.com about preventing SQL injection and also at the official Python SQLite documentation . Noted security expert Bruce Schneier (who often quotes xkcd) mentioned a similar attack that happened in the 2010 Swedish general elections, and several people tried it on Randall's color survey . In 1253: Exoplanet Names , someone (presumably Mrs. Roberts) attempts to perform a similar trick, submitting the name e'); DROP TABLE PLANETS;-- to the IAU. It is later revealed in 342: 1337: Part 2 that the daughter's middle name is Elaine (full name: Help I'm trapped in a driver's license factory Elaine Roberts ). This is thus the first time Elaine is mentioned. This comic was, presumably, a setup for the " 1337 " series where both of the hacker mom's kids are shown for the first time. This comic is available as a signed print in the xkcd store . In 2020 this happened in real life: Company made to change name that could be used for website hacks .

Eggs

Eggs

https://www.xkcd.com/328

https://www.explainxkcd.com/wiki/index.php/328:_Eggs

[Megan sits at a bar; Beret Guy cleans a glass from behind the counter. Cueball approaches.] Cueball: So, how do you like your eggs in the morning? Megan: Ooh, sunny side up. Cueball: Oh. Huh. Megan: Is that a problem? Cueball: Well, it's just that I was trying to set you up for the "unfertilized" line. Megan: Ah. Bad timing; I'm actually looking for casual sex. ...interested? Cueball: I'd love to, but I've got like 20 more jokes to set up tonight. Hey, have you seen a priest and a rabbi?

At a bar, Cueball uses what appears to be a common cheesy pick-up line: "So, how do you like your eggs in the morning?" — implying that he will be the one cooking them, because they will still be together in the morning, after they spent the night having sex. For women who do not appreciate such paltry attempts at soliciting sexual intercourse, a sardonic counter-response to the pick-up line is "unfertilized," which switches the meaning of "eggs" from chicken eggs to female gametes , expressing the sentiment that they do not wish to have sex. However, in this scenario, it turns out Cueball is not actually trying to solicit sex from Megan at all, but is just interested in setting up jokes. Megan's desire for actual casual sex therefore subverts his plan for comedy. He politely declines her offer and tries instead with a different joke using the classic snowclone priest and rabbi setup. The title text continues the conversation, where Megan reveals that the bar is actually a "casual sex bar" and further suggests that priests and rabbis do in fact come to the bar frequently. This is in contrast to real life, where women in bars are generally not interested in casual sex, [ citation needed ] and such bars would probably not be frequented by religious leaders. [Megan sits at a bar; Beret Guy cleans a glass from behind the counter. Cueball approaches.] Cueball: So, how do you like your eggs in the morning? Megan: Ooh, sunny side up. Cueball: Oh. Huh. Megan: Is that a problem? Cueball: Well, it's just that I was trying to set you up for the "unfertilized" line. Megan: Ah. Bad timing; I'm actually looking for casual sex. ...interested? Cueball: I'd love to, but I've got like 20 more jokes to set up tonight. Hey, have you seen a priest and a rabbi?

Turing Test

Turing Test

https://www.xkcd.com/329

https://www.explainxkcd.com/wiki/index.php/329:_Turing_Test

[Cueball typing at a desk with two computers; there is a caption above him.] Turing test extra credit: Convince the examiner that he's a computer. Cueball: You know, you make some really good points. Cueball: I'm... not even sure who I am anymore.

In brief, a Turing test is a test for assessing whether a machine/program demonstrates "intelligent" behaviour. Suggested by Alan Turing , the test involves a human examiner talking through a computer terminal to either a human or a computer — which it is, is not known to the examiner. If the machine/program's responses convince the examiner that he/she is talking to a human, the machine/program is said to be passing the test. This comic suggests that extra credit should be awarded if the machine/program is capable of "counter-convincing" the examiner that he's actually a computer. The most common implementation of a Turing test Internet users may see is the CAPTCHA (Completely Automated Program to Tell Computers and Humans Apart), which is often found on web site registration pages and usually involves trying to identify letters/numbers in an image. The text in the image is often distorted and/or in different colors or sizes or fonts, or may be very blurry as if from a very bad photocopy. This is to deter an automated OCR (Optical Character Recognition) program from easily identifying the characters. The idea is that humans can process and decipher things from highly distorted pictures much easier than (current) computer algorithms can. The caption makes a play on words, in that extra credit (optional additional work to perform) is sometimes offered on curricular examinations ("tests") to allow the taker to increase their total score by demonstrating a heightened understanding of the subject, but the Turing test is not such a test. (This misapplication of vernacular associated with academic testing to a non-academic procedure that also bears the name test is a common vehicle of humor, as in "what if I take a blood test, and don't pass?" One may pass or fail an academic exam, but a blood test only identifies blood type, and the concept of passing or failing is not applicable.) Similarly, the title text makes a play on words with "test-ees" vs testes suggesting that such extra credit would be an ironic twist to Turing test. (Hitting or kicking an adversary in the testes is considered dirty fighting.) This play on words is actually itself a form of aural CAPTCHA; humans can processes and recognize puns for what they are, but machines generally run afoul of the ambiguity. (Unless Randall trained them for it as in 1696: AI Research .) A person with an appreciation for macabre humor will note that actually hitting Alan Turing in the testes would be rendered somewhat ineffectual by the fact that the British government chemically castrated him after he was convicted of "gross indecency" (Victorian-era code for homosexual acts between men) under the Labouchere Amendment in 1952. Whether or not this was intended by Randall is uncertain. [Cueball typing at a desk with two computers; there is a caption above him.] Turing test extra credit: Convince the examiner that he's a computer. Cueball: You know, you make some really good points. Cueball: I'm... not even sure who I am anymore.

Indecision

Indecision

https://www.xkcd.com/330

https://www.explainxkcd.com/wiki/index.php/330:_Indecision

[Cueball is lying on the floor with his friend.] Cueball: So what do you want to do? Friend: Still no ideas. Cueball: Wait, I think there's a rule about this. [Cueball goes to bookshelf and removes a book called "Rules".] [The book of rules is opened to the following: RULE social.b.99.1 If friends spend more than 60 minutes deciding what to do, they must default to sexual experimentation. [Cueball is standing, holding the book. The friend is in the process of standing up.] Cueball: Huh. Friend: I did not know that rule. Cueball: Me neither. Friend: I'll go get the Crisco. A book suggesting a more or less unrelated solution that is accepted anyway is also pulled from a shelf in 1024 .

These two friends (both presumably male, since female characters in xkcd are depicted with hair) are surprisingly cavalier in taking the suggestion to engage in sexual experimentation to alleviate boredom. Even if both men are gay, the fact that they're friends (as the rule in the book describes them) suggests that they are not currently having sex on a regular basis. In this case - and even more so if the friends are heterosexual - most people would not take the book's suggestion, and it may even make them feel embarrassed and awkward. [ citation needed ] The book that one of the Cueballs grabs appears to be some sort of all-encompassing rule book, its reach including the social sphere. Obviously this book is fictional, but the line "I think there's a rule about this" sounds like a reference to folk "rules" or guidelines like the " five-second rule ." Crisco is a brand of shortening, a fat that is solid at room temperature and frequently used in baking, though is also sometimes used as a sexual lubricant. In this instance, it's implied that it will be used as a sexual lubricant. Crisco was referenced again in a sexual context in the title text of 414: Mistranslations and later as a part of a weird dream also in the title text of 557: Students . The title text could be spoken by either one of the characters or Randall . It attempts to preempt any awkwardness or judgment the reader may have about this situation by transferring responsibility to the rule book. [Cueball is lying on the floor with his friend.] Cueball: So what do you want to do? Friend: Still no ideas. Cueball: Wait, I think there's a rule about this. [Cueball goes to bookshelf and removes a book called "Rules".] [The book of rules is opened to the following: RULE social.b.99.1 If friends spend more than 60 minutes deciding what to do, they must default to sexual experimentation. [Cueball is standing, holding the book. The friend is in the process of standing up.] Cueball: Huh. Friend: I did not know that rule. Cueball: Me neither. Friend: I'll go get the Crisco. A book suggesting a more or less unrelated solution that is accepted anyway is also pulled from a shelf in 1024 .

Photoshops

Photoshops

https://www.xkcd.com/331

https://www.explainxkcd.com/wiki/index.php/331:_Photoshops

[Megan holds a sword while Cueball looks on.] My hobby: Insisting that real-life objects are photoshopped. Megan: This sabre is a 19th-century family heirloom. Cueball: It looks photoshopped. Megan: Huh? Cueball: Yeah, the reflections are all wrong. Definitely photoshopped.

This whole comic, including the title text, are a play on the then-popular internet meme " This Looks Shopped ." It may also be making fun of how everything and anything you find on the internet has someone insisting that it's 'fake' or 'photoshopped', regardless of whether it's true in actuality. Adobe Photoshop is a popular image manipulation tool . It is used to manipulate photographic images and for drawing. Of course, Photoshop and similar tools like Paint Shop Pro can only be used for imagery, not for real life objects. The title text contains the second part of the internet meme, the complete text of which is: "THIS LOOKS SHOPPED / I CAN TELL FROM SOME OF THE PIXELS AND FROM SEEING QUITE A FEW SHOPS IN MY TIME." Quite a few interesting images have been uncovered as "shopped" using various techniques. Some examples: shadows are in the wrong direction, extra hands appear, movie stars are made thinner, wrinkles or spots are removed, and objects are added or removed. This of course triggered the start of the meme. JPEG is an image compression algorithm that works by finding frequencies in blocks of 8x8 pixels and saving that instead of the original pixels. This works remarkably well, but sometimes leaves artifacts that can be seen when zooming in enough. The iris of an eye contains all kinds of odd colored spots - and there's not a JPEG algorithm in sight. This is another strip in the My Hobby series. [Megan holds a sword while Cueball looks on.] My hobby: Insisting that real-life objects are photoshopped. Megan: This sabre is a 19th-century family heirloom. Cueball: It looks photoshopped. Megan: Huh? Cueball: Yeah, the reflections are all wrong. Definitely photoshopped.

Gyroscopes

Gyroscopes

https://www.xkcd.com/332

https://www.explainxkcd.com/wiki/index.php/332:_Gyroscopes

[Cueball sits at a desk with a gyroscope in his hands. Text on top of the frame:] Despite years of studying physics, I still find gyroscopes a little freaky. [Cueball starts the gyroscope.] Gyroscope: zzzzip [The gyroscope spins.] Gyroscope: zzzzzz [Frameless panel, the gyroscope lifts into the air.] [The gyroscope moves away from Cueball, still spinning.] Gyroscope: G R E E T I N G S, H U M A N.

Cueball is playing with a gyroscope . Even though he has studied them and intellectually understands their behaviour, they still seem somewhat mysterious. At the end of the comic, the gyroscope is revealed to have the power of levitation and to apparently be a sentient lifeform (it talks to him). In the title text, Randall is mocking the Moon landing conspiracy theories and refers to the lunar precession in process. Gyroscopes and the lunar orbit both exhibit precession, a physical concept that non-scientists can find hard to grasp. Thus, it is a perfect subject for a lunar conspiracy theory. He goes on to claim that gyroscopes (which form part of the navigation system of every commercial airplane) were directly responsible for the 9/11 terrorist attacks. [Cueball sits at a desk with a gyroscope in his hands. Text on top of the frame:] Despite years of studying physics, I still find gyroscopes a little freaky. [Cueball starts the gyroscope.] Gyroscope: zzzzip [The gyroscope spins.] Gyroscope: zzzzzz [Frameless panel, the gyroscope lifts into the air.] [The gyroscope moves away from Cueball, still spinning.] Gyroscope: G R E E T I N G S, H U M A N.

Getting Out of Hand

Getting Out of Hand

https://www.xkcd.com/333

https://www.explainxkcd.com/wiki/index.php/333:_Getting_Out_of_Hand

[A couple is in bed in the dark, and Cueball reaches out from under the covers to do a Wikipedia search about Foreplay.]

Given how Wikipedia has an ever-expanding variety of topics, the grand majority of them in great detail, there is a possibility (even a temptation) of relying on Wikipedia to learn from every topic that leaves you confused... even foreplay . ('Bedtime' and 'us time' are not necessarily 'computer time'.) This comic may also be a reference to how people can get addicted to reading Wikipedia pages, because there are many interesting links on each page that people haven't read yet, and there are links on that page that they click on, etc. The title text refers to the fact that many rely on Wikipedia instead of remembering/learning stuff. Reliance on Wikipedia was later directly addressed as the subject of 903: Extended Mind . [A couple is in bed in the dark, and Cueball reaches out from under the covers to do a Wikipedia search about Foreplay.]

Wasteland

Wasteland

https://www.xkcd.com/334

https://www.explainxkcd.com/wiki/index.php/334:_Wasteland

[Cueball is walking through a wasteland talking to himself.] Cueball: I am alone in this wasteland, a thousand miles from you. Cueball: But I haven't forgotten the feel of your skin, your mischievous smile. Cueball: You'd think a thousand miles would be enough. Cueball: I guess I'll keep walking.

At the beginning of the comic, Cueball is wandering around in a barren area, supposedly a desert, thinking about his ex-partner, in which he, at first, appears to be fondly remembering him/her, but the last two boxes explain that he is trying to take a long walk to forget him/her, and is obviously not very good at it. The title text implies that his ex-partner had easily forgotten him, and he wishes that he could forget more easily. It's also possible that he means that it's so hard to forget him/her that forgetting anything else is simple in comparison to it. There is a similar twist in comics 71: In the Trees and 1042: Never . Note: When Cueball mentions walking 1000 miles, he may be exaggerating, as, due to his lack of hiking/traveling gear, most likely has only walked a hundred or so, either that, or the story is similar in nature, or even in the same universe, as comic 505 . Though this might also be a nod to a What If question about how long it would take for two immortal people to find each other on a barren planet. [Cueball is walking through a wasteland talking to himself.] Cueball: I am alone in this wasteland, a thousand miles from you. Cueball: But I haven't forgotten the feel of your skin, your mischievous smile. Cueball: You'd think a thousand miles would be enough. Cueball: I guess I'll keep walking.

Mattress

Mattress

https://www.xkcd.com/335

https://www.explainxkcd.com/wiki/index.php/335:_Mattress

[Megan and Cueball are cuddling.] Cuddling face-to-face is nice, but we can never figure out where to put our lower arms. Our solution: the Cuddle Mattress! Your lower arms fit in the convenient gap. [There is a diagram of a mattress with a notch cut through it at shoulder level. The gap is indicated with an arrow.] [The same couple is shown again, cuddling snugly on the mattress.] [Cueball and Megan are giving a presentation to another person. Cueball has a pointer and a clicker for the slides that are projected on the screen next to him.] Listener: Oh man, that's ALWAYS bothered me. Listener: I want one. Listener: Although... so the lower arms just sort of dangle? Listener: What do you do with them? Cueball: It was a bit awkward. Clicker: click Megan: Then we had a second breakthrough. [The couple is shown again on the cuddle mattress, this time in more detail and facing the tops of their heads. Their lower arms are sticking through the gap in the mattress and playing a conveniently located game of Rock 'em Sock 'em Robots.] Cueball: click click Blue Robot: punch Red Robot: punch Megan: click click

A commonly cited problem with cuddling is that whatever arms you and your partner are lying on tend to fall asleep from your and/or your partner's weight, and are in any case not very comfortable to be lying upon. Here Cueball and Megan have invented a mattress with a slot in it to solve that problem. To provide an activity for their lower arms when they are comfortably placed in that slot, they have installed a game of " Rock 'Em Sock 'Em Robots " underneath the bed. The humour arises from the juxtaposition of a sedate activity like cuddling with a boisterous activity like "Rock 'Em Sock 'Em Robots" with the implication that Megan and Cueball are doing both at once. The title text refers to a series of commercials for Tempur-Pedic mattresses where the presenter would place a wine glass on the mattress and then jump up and down somewhere else on the mattress. The fact that the wine did not spill was meant to indicate that one partner's motions would not disturb the other. It is implied that he did that test on this mattress and fell into the slot, breaking his ankle in the process. [Megan and Cueball are cuddling.] Cuddling face-to-face is nice, but we can never figure out where to put our lower arms. Our solution: the Cuddle Mattress! Your lower arms fit in the convenient gap. [There is a diagram of a mattress with a notch cut through it at shoulder level. The gap is indicated with an arrow.] [The same couple is shown again, cuddling snugly on the mattress.] [Cueball and Megan are giving a presentation to another person. Cueball has a pointer and a clicker for the slides that are projected on the screen next to him.] Listener: Oh man, that's ALWAYS bothered me. Listener: I want one. Listener: Although... so the lower arms just sort of dangle? Listener: What do you do with them? Cueball: It was a bit awkward. Clicker: click Megan: Then we had a second breakthrough. [The couple is shown again on the cuddle mattress, this time in more detail and facing the tops of their heads. Their lower arms are sticking through the gap in the mattress and playing a conveniently located game of Rock 'em Sock 'em Robots.] Cueball: click click Blue Robot: punch Red Robot: punch Megan: click click

Priorities

Priorities

https://www.xkcd.com/336

https://www.explainxkcd.com/wiki/index.php/336:_Priorities

[A teacher is talking to a student, sitting at a desk.] Teacher: If you don't turn in at least one homework assignment, you'll fail this class. [The student holds up his report card.] Student: Yeah. But if I can fail this class, the grades on my report card will be in alphabetical order!

In this comic, Cueball is a student, who apparently didn't turn in his homework assignment repeatedly, for which he gets a warning from his Cueball-like teacher. In some schools in the United States, a student's grades are determined mainly using letters for quick reference. In most schools, the letter grades are given as follows: A — 100%–90% B — 89%–80% C — 79%–70% D — 69%–60% F — 59%–0% Traditionally, these schools send ' report cards ' in which the student's current grading of the semester or even the entirety of the class the student is taking is denoted using these letters, for example: English — A Mathematics — D Science — B Social Studies — B World Building — C The student may have noted that, if he aims for certain scoring (for example: altering the quality of his homework or even sending out his homework only at the times needed for his grades to reach a certain level), he could make the report card spell every letter grade in alphabetical order. Deriving from the previous example, the student would aim for the following report card: English — A Mathematics — B Science — C Social Studies — D World Building — F Interestingly, since in some schools even a 0% grade would produce the required 'F' grade, the student does not need to work at all (not even turn in any school assignments) to get the required 'F' grade, this leading to the situation presented in the comic above. Rather than a letter upon a continuum (as it might be assumed if 'E' were not skipped) it is generally accepted that 'F' actually stands for 'Failed' and covers any situation where insufficient credit was gained to obtain any other letter-grade. There are some schools, though, where turning in nothing would result in the class being marked "incomplete" or "inc" instead of having a grade shown at all. The title text references that, not only can the grades in the report card inadvertently spell out certain words (for example: 'CAB' or 'FAD'), but also that the letter grade system denoted omits the letter 'E' in standard letter grading. The reason for the missing "E" is complex and explained in this Slate article . However, this is not universal in the United States: Ohio State University, for example, uses 'E' for failing. [A teacher is talking to a student, sitting at a desk.] Teacher: If you don't turn in at least one homework assignment, you'll fail this class. [The student holds up his report card.] Student: Yeah. But if I can fail this class, the grades on my report card will be in alphabetical order!

Post Office Showdown

Post Office Showdown

https://www.xkcd.com/337

https://www.explainxkcd.com/wiki/index.php/337:_Post_Office_Showdown

[Cueball is in a post office wearing earphones connected to his iPod. There are several other people, including an old version of White Hat at the counter with a cane and Hairbun with a long narrow box entering the office by the door. Behind the counter, Ponytail stands together with a Cueball-like guy. Another person is obscured by the lowest of the three connected thought bubbles emanating from Cueball to the left. A fourth thought bubble is below Cueball to the right. Above all this is a caption:] I spend a lot of time mentally choreographing elaborate fight scenes with strangers around me. Cueball's thoughts: Okay - if that old man pulls a crossbow, Cueball's thoughts: I'll throw the postal scale at him and dive backward behind the stamps machine. Cueball's thoughts: But what if the lady by the door has a katana in that box? Cueball's thoughts: Better set my iPod to the "Kill Bill" fight theme, just in case.

Action movies, such as " Kill Bill " by Quentin Tarantino , often feature elaborate fight scenes in mundane environments. Cueball , here wearing earphones connected to his iPod, is often imagining himself in such a situation, for instance as in this comic, while at the post office. This makes the comic related to the My Hobby series. First, Cueball imagines that the old man (an old version of White Hat with a cane) pulls out a crossbow and how he would react to that. But then, he continues to imagine that Hairbun has a katana samurai sword in the box. So this could be a long fight, so he decides to be ready for it by setting his iPod to play the "Kill Bill" fight theme. In Kill Bill, there is a long fight scene with samurai swords. The title text refers to two songs: " Battle Without Honor or Humanity " from the soundtrack of "Kill Bill," and " Ride of the Valkyries " by Richard Wagner , the latter being associated with fighting scenes because of a famous sequence in the movie " Apocalypse Now " by Francis Ford Coppola . He notes that these two songs will absolutely improve any activity, not only fight scenes. [Cueball is in a post office wearing earphones connected to his iPod. There are several other people, including an old version of White Hat at the counter with a cane and Hairbun with a long narrow box entering the office by the door. Behind the counter, Ponytail stands together with a Cueball-like guy. Another person is obscured by the lowest of the three connected thought bubbles emanating from Cueball to the left. A fourth thought bubble is below Cueball to the right. Above all this is a caption:] I spend a lot of time mentally choreographing elaborate fight scenes with strangers around me. Cueball's thoughts: Okay - if that old man pulls a crossbow, Cueball's thoughts: I'll throw the postal scale at him and dive backward behind the stamps machine. Cueball's thoughts: But what if the lady by the door has a katana in that box? Cueball's thoughts: Better set my iPod to the "Kill Bill" fight theme, just in case.

Future

Future

https://www.xkcd.com/338

https://www.explainxkcd.com/wiki/index.php/338:_Future

[The comic has three panels. In the first panel, Hairy and Megan are holding hands. There is a voice bubble originating from Cueball standing in the third panel.] Cueball: Come explore the future with me! [Megan says something, which goes to the third panel.] [The two voice bubbles cross in the middle of the second panel.] [Megan's voice bubble:] Megan: I can't.

Cueball is in the last panel (the future) but somehow manages to get his message into the first panel (the past). Megan answers in the first panel, but somehow her message gets to Cueball in the last panel. This comic can be interpreted in several ways. First, it is not clear if Cueball's question is intended for Megan alone, for Hairy alone, for both Megan and Hairy , or at the past world in general. If the question is intended for several people, the comic is just about how one could sometimes desire to know the future without waiting for it; however, time flows at its usual rate, and there's no way around this. If the question is intended only for Megan, it likely means Cueball is asking Megan to become his girlfriend. She answers she can't, maybe because, as before, time runs at its usual rate and she can't go faster; or maybe because she's already with Hairy (they're shown holding hands), and she's not leaving Hairy for Cueball. Finally, the Cueball in the future could just be the very same person as the Hairy in the past, having become bald as he gets older. In this scenario, Cueball is just missing Megan, who was with him in the past but no longer is, maybe even because she has died in between. In the title text, Cueball seems to be considering going back to the past, but he rejects doing so because, having seen the future, now the past doesn't look attractive. [The comic has three panels. In the first panel, Hairy and Megan are holding hands. There is a voice bubble originating from Cueball standing in the third panel.] Cueball: Come explore the future with me! [Megan says something, which goes to the third panel.] [The two voice bubbles cross in the middle of the second panel.] [Megan's voice bubble:] Megan: I can't.

Classic

Classic

https://www.xkcd.com/339

https://www.explainxkcd.com/wiki/index.php/339:_Classic

[Cueball is sitting in front of a turntable, listening to Stairway to Heaven by Led Zeppelin. A guitarist (possibly meant to be Jimmy Page) can be seen in an inset in the top left corner of the first two panels.] Song: And as we wind on down the road, our shadows taller than our soul Song: When all is one and one is all, to be a rock and not to rooooll Song [fading away]: And she's buying a stairway to Heaven Cueball: Man. The Baby Boomers are kicking our ASSES . Cueball: We need to get it together, guys.

Cueball listens to the song " Stairway to Heaven " performed by Led Zeppelin using an old phonograph . Led Zeppelin was active during the 1970s, with Stairway To Heaven being released in 1971; as such, the music belongs to the Baby Boomer generation . After the song fades out to the end, he expresses how much it's affected him by stating that the baby boomers are winning over his own generation at music. The way in which the lyrics are written evokes the sound of this particular song as it finishes and fades out. The title text likely refers to Lim Jeong-hyun , the guitarist in the YouTube video guitar that went viral in 2006-2007, in which he performed a cover of "Canon Rock," a rock arrangement of Pachelbel's Canon . Alternatively, it may refer to JerryC , the original composer of "Canon Rock," who also performed the song in a YouTube video , though his video did not gain as much popularity as Lim's. The Classical era was a period in music history (1750 - 1820) that produced many musical compositions still remembered hundreds of years afterward, and the word 'classic' is now used to describe something that remains popular long after its time. The "Baby Boomer generation" is known for having created many musicians still well-loved today, including: [Cueball is sitting in front of a turntable, listening to Stairway to Heaven by Led Zeppelin. A guitarist (possibly meant to be Jimmy Page) can be seen in an inset in the top left corner of the first two panels.] Song: And as we wind on down the road, our shadows taller than our soul Song: When all is one and one is all, to be a rock and not to rooooll Song [fading away]: And she's buying a stairway to Heaven Cueball: Man. The Baby Boomers are kicking our ASSES . Cueball: We need to get it together, guys.

Fight

Fight

https://www.xkcd.com/340

https://www.explainxkcd.com/wiki/index.php/340:_Fight

We had a fight last night. [Cueball is sitting in a sofa, head in both hands, feeling upset.] I guess she's still mad. [Megan is standing with arms crossed in front of her chest, with the same mood.] I woke up to find she'd written a sappy love note [Cueball is standing in front of a computer, with a cup in his hand.] to my boot sector. [The cup now lies on the floor, Cueball is looking at the computer with disbelief.] Computer: Operating system not found

The boot sector of a hard drive is where the information for operating systems is stored. It tells the computer to load a program; in most cases, this is an operating system. If this sector is overwritten, an operating system stored on the drive can't be booted into. (Fortunately, repairing a blanked or corrupted boot sector is surprisingly easy, although doing so usually requires the system to be booted from the installation media for the operating system on the drive.) The first two panels indicate that Megan is still mad at Cueball from a fight from the night before, and the third panel shows promise of her forgiving him through an overly affectionate love note. However, the last panel reveals that she used the love note to overwrite the boot sector of Cueball 's computer out of anger. The .conf files of Linux - and Unix -based systems are text based files where all the settings for various applications are stored. Since all the configurations were replaced with "sweet nothings" - whispered lovers' talk, or literal nothings (blank space or meaningless jumbles of characters) - none of the programs work as they should. X is the X Window System , the most common GUI framework used on modern Linux and Unix systems. Once upon a time, it was notoriously hard to configure correctly, even when starting from a known good configuration, let alone a destroyed one. (More recent versions of X configure themselves correctly for most users without a .conf file.) We had a fight last night. [Cueball is sitting in a sofa, head in both hands, feeling upset.] I guess she's still mad. [Megan is standing with arms crossed in front of her chest, with the same mood.] I woke up to find she'd written a sappy love note [Cueball is standing in front of a computer, with a cup in his hand.] to my boot sector. [The cup now lies on the floor, Cueball is looking at the computer with disbelief.] Computer: Operating system not found

1337 Part 1

1337: Part 1

https://www.xkcd.com/341

https://www.explainxkcd.com/wiki/index.php/341:_1337:_Part_1

[Cueball talks to his Cueball-like friend who is lying down on the floor, using his laptop. Cueball is pointing at the laptop.] Cueball: You're not on the neighbor's WiFi, are you? Friend: Yeah, why? Cueball: The admin... plays games. Friend: No problem. I'll just hop on a secure VPN. [Cueball's friend now sits on his knees in front of his laptop frantically typing. A message from the laptop comes out with a zig-zag line.] Friend: Whoa, my connections are dying as soon as I start to tunnel anything! Message on laptop: A VPN? How cute! And stop trying to SSH. Friend: Holy shit! Someone's inserting notes into the pages I request! Editing the TCP stream live! Friend: Nobody's that fast. Who is this admin? [In a frameless panel, Mrs. Roberts with a hot bun tray in one hand (indicated with five wiggly lines above the buns), with oven mitts on both hands, typing on her desktop computer on a table.] Mrs. Roberts: My goodness. Neighborhood scamps on the wireless. Taptaptaptap [Cueball is standing with a hand toward his now standing friend, the laptop lies between them.] Cueball: I should have warned you about Mrs. Roberts. Friend: How does she type with oven mitts!? Cueball: You've been pwned pretty hard, man. You might want to sit down.

This is the first part of five in the " 1337 " series. The title 1337 is "L-eet," or "elite," using the Leet alphabet, a coding system used primarily on the internet (and on early text messaging system), meant to provide a bit of obfuscation to plain text both to make it harder to read, and to show off in a creative way using in-group jargon. All comics in the series: This series was released on 5 consecutive days (Monday-Friday, probably because he wanted to release comic 404 on april fools' day) and not over the usual Monday/Wednesday/Friday schedule. If a wireless network (Wi-Fi) is unsecured, it is usually a sign that the owner of the access point is not technically skilled enough to go into the admin panel and enable encryption. Obviously, someone in the area who wants to get on the net, but doesn't have a mobile data connection, will simply use this open access point. However, it is also common practice to leave open an access point to be able to claim that infringement of copyright may not have been the homeowner, but that anybody could have connected to the access point and started downloading files. Another fun trick, for administrators of open APs, is to intercept pages and edit their contents . The only way to stop this is to create a secure connection, or tunnel, to a server to stop the admin from playing man-in-the-middle . Of course, as the title text says, Mrs. Roberts is so cool, she can edit the TCP stream live, without the help of programs, but then there is help to get with tools like the Upside-Down-Ternet , if you wish to play games with people misusing your Wi-Fi. Not only is Mrs. Roberts awesome enough to manually edit the live TCP stream, she's also manually ending individual VPN and SSH connections as Cueball's Cueball-like friend makes them - while wearing oven mitts and baking cookies at the same time. He has been pwned (i.e. owned) by Mrs. Roberts. The question "How does she type with oven mitts?" is likely a reference to the old web video site Homestar Runner and its character of Strong Bad , who answered emails while wearing boxing gloves. "How does he type with boxing gloves?" was the most common question he received. Another unanswered question is how Cueball's friend knew she was typing with gloves on; however, the answer is probably that since they were neighbors, they could see her through the window. [Cueball talks to his Cueball-like friend who is lying down on the floor, using his laptop. Cueball is pointing at the laptop.] Cueball: You're not on the neighbor's WiFi, are you? Friend: Yeah, why? Cueball: The admin... plays games. Friend: No problem. I'll just hop on a secure VPN. [Cueball's friend now sits on his knees in front of his laptop frantically typing. A message from the laptop comes out with a zig-zag line.] Friend: Whoa, my connections are dying as soon as I start to tunnel anything! Message on laptop: A VPN? How cute! And stop trying to SSH. Friend: Holy shit! Someone's inserting notes into the pages I request! Editing the TCP stream live! Friend: Nobody's that fast. Who is this admin? [In a frameless panel, Mrs. Roberts with a hot bun tray in one hand (indicated with five wiggly lines above the buns), with oven mitts on both hands, typing on her desktop computer on a table.] Mrs. Roberts: My goodness. Neighborhood scamps on the wireless. Taptaptaptap [Cueball is standing with a hand toward his now standing friend, the laptop lies between them.] Cueball: I should have warned you about Mrs. Roberts. Friend: How does she type with oven mitts!? Cueball: You've been pwned pretty hard, man. You might want to sit down.

1337 Part 2

1337: Part 2

https://www.xkcd.com/342

https://www.explainxkcd.com/wiki/index.php/342:_1337:_Part_2

[Cueball standing an looking down at his Cueball-like friend, who is sitting on the floor near an armchair holding a cloth to his face.] Friend: So the greatest hacker of our era is a cookie-baking mom? Cueball: Second-greatest. Friend: Oh? [The next panel is only half height as Cueball's narration is written as a caption above the panel without a frame around it. In the panel to the left lies a young Elaine with a ponytail on the floor typing at a keyboard while looking at a screen connected to a computer behind it with lots of wires and open case. The computer appears to have been pieced together and there is a screwdriver lying next to her and an open box lies behind her. Little Bobby Tables (a kid version of Cueball) is painting with a broad brush at an easel to the left. There is a clear drawing with two parts going up and one down, but it's not easy to see what it should look like. He is holding his other hand up in the air, like he is enjoying the painting.] Cueball (narrating): Mrs. Roberts had two children. Her son, Bobby, was never much for computers, but her daughter Elaine took to them like a ring in a bell. [The front of a car is in frame with side mirror and steering wheel visible. Mrs. Roberts is waving goodbye to her daughter who is wearing a backpack and is holding a walking stick. She is about to begin climbing a staircase built into a rocky mountain side. The first 11 step are visible. Behind the two and the stair are two distant mountain peaks, and above them two clouds. Cueball continues to narrate, this time inside the panel:] Cueball (narrating): When Elaine turned 11, her mother sent her to train under Donald Knuth in his mountain hideaway. [Donald Knuth, drawn with hair only around his neck, is standing with a pointing stick at a chalk board with graph traversal patterns on it and two blocks of unreadable text the top may be a matrix. This small panel is also lower than the next panel, with Cueballs narration above:] Cueball (narrating): For four years she studied algorithms. Donald Knuth: Child— [Donald Knuth whips around from the board slashing the stick like a sword. Elaine jumps, making a somersault (indicated with a line curving on it self from floor to sword) and lands on the stick balancing with her arms out.] Donald Knuth: Why is A* search wrong in this situation? Stick: swish Elaine: Memory usage! Donald Knuth: What would you use? Elaine: Dijkstra's algorithm! [Donald Knuth and Elaine are outside, seen from behind while they are both writing on a chalkboard with a thick line down the middle to separate their work. On both sides their writing can be seen but it is unreadable. Where there is only text visible on Donald Knuth's side there is also what appears to be a drawing or matrix at the top of Elaine's. But a similar thing could be behind Donald Knuth's head. Elaine is no longer wearing her hair in a ponytail but have long straight white hair like her mom Mrs. Roberts. To the left there is a stump from a tree, some grass and maybe a puddle of water. Further back there is a small jagged hill and a flat horizon. To the right there are four mountain peaks and a flat high plateau towards the horizon. The frame of the panel does not include the top and bottom corner, but cuts a rectangular section of both places. In these two sections outside the panel is the last two paragraphs of Cueball's narrating:] Cueball (narrating): Until one day she bested her master Donald Knuth: So our lower bound here is O(n log n) Elaine: Nope. Got it in O(n log (log n)) Cueball (narrating): And left.

This is the second part of five in the " 1337 " series. The title 1337 is "L-eet," or "elite," using the Leet alphabet, a coding system used primarily on the internet (and on early text messaging system), meant to provide a bit of obfuscation to plain text both to make it harder to read and to show off in a creative way using in-group jargon. All comics in the series: This series was released on 5 consecutive days (Monday-Friday, probably because he wanted to release comic 404 on april fools' day) and not over the usual Monday/Wednesday/Friday schedule. "Like a ring in a bell" appears to be a reference to the Chuck Berry song Johnny B. Goode , in which Berry describes a young boy (like himself) who becomes a guitar-playing prodigy. The original lyric was "just like a-ringing a bell." Apparently, Elaine learned to program as quickly, easily, and skillfully as Johnny (and Chuck) learned to play rock 'n' roll. Donald Knuth is a computer science Professor Emeritus at Stanford University who is famous for writing The Art of Computer Programming and developing the T e X computerized typesetting system. He may not have a mountain hideaway (a reference to Kill Bill , by the way as is the whole training sequence), but he would be one of the best mentors a budding hacker could have. The A* search algorithm and Dijkstra's algorithm are graph search algorithms . And what study of algorithms would be complete without a healthy study about finding complexities? Time complexity is the amount of time an algorithm takes to execute. Upper and lower bounds for complexity is written in Big O notation . Best possible execution of an algorithm is constant time, or O(1), said in words, for any given data set, no matter how large, the algorithm will always return the answer in the same time. However, constant time is extremely difficult to achieve; linear time (O(n)) is also very good. For more complex algorithms, O( n*log(n) ) is good, but O( n*log(log(n)) ) is better. (Note that logarithms in different bases are proportional to each other. So this would hold true for any base >1.) From the evidence that Mrs. Roberts has two children, a daughter named Elaine , and a younger son named Bobby (presumably Little Bobby Tables aka "Robert'); DROP TABLE students;--"), we can assume that she is the same mother from 327: Exploits of a Mom . Of course, the title text here explains that Elaine is only her middle name (assuming canonicity of title-text). In the title text to 327: Exploits of a Mom , we learned that her first name is "Help I'm trapped in a driver's license factory". Mrs. Roberts appears to have had fun naming her children. [Cueball standing an looking down at his Cueball-like friend, who is sitting on the floor near an armchair holding a cloth to his face.] Friend: So the greatest hacker of our era is a cookie-baking mom? Cueball: Second-greatest. Friend: Oh? [The next panel is only half height as Cueball's narration is written as a caption above the panel without a frame around it. In the panel to the left lies a young Elaine with a ponytail on the floor typing at a keyboard while looking at a screen connected to a computer behind it with lots of wires and open case. The computer appears to have been pieced together and there is a screwdriver lying next to her and an open box lies behind her. Little Bobby Tables (a kid version of Cueball) is painting with a broad brush at an easel to the left. There is a clear drawing with two parts going up and one down, but it's not easy to see what it should look like. He is holding his other hand up in the air, like he is enjoying the painting.] Cueball (narrating): Mrs. Roberts had two children. Her son, Bobby, was never much for computers, but her daughter Elaine took to them like a ring in a bell. [The front of a car is in frame with side mirror and steering wheel visible. Mrs. Roberts is waving goodbye to her daughter who is wearing a backpack and is holding a walking stick. She is about to begin climbing a staircase built into a rocky mountain side. The first 11 step are visible. Behind the two and the stair are two distant mountain peaks, and above them two clouds. Cueball continues to narrate, this time inside the panel:] Cueball (narrating): When Elaine turned 11, her mother sent her to train under Donald Knuth in his mountain hideaway. [Donald Knuth, drawn with hair only around his neck, is standing with a pointing stick at a chalk board with graph traversal patterns on it and two blocks of unreadable text the top may be a matrix. This small panel is also lower than the next panel, with Cueballs narration above:] Cueball (narrating): For four years she studied algorithms. Donald Knuth: Child— [Donald Knuth whips around from the board slashing the stick like a sword. Elaine jumps, making a somersault (indicated with a line curving on it self from floor to sword) and lands on the stick balancing with her arms out.] Donald Knuth: Why is A* search wrong in this situation? Stick: swish Elaine: Memory usage! Donald Knuth: What would you use? Elaine: Dijkstra's algorithm! [Donald Knuth and Elaine are outside, seen from behind while they are both writing on a chalkboard with a thick line down the middle to separate their work. On both sides their writing can be seen but it is unreadable. Where there is only text visible on Donald Knuth's side there is also what appears to be a drawing or matrix at the top of Elaine's. But a similar thing could be behind Donald Knuth's head. Elaine is no longer wearing her hair in a ponytail but have long straight white hair like her mom Mrs. Roberts. To the left there is a stump from a tree, some grass and maybe a puddle of water. Further back there is a small jagged hill and a flat horizon. To the right there are four mountain peaks and a flat high plateau towards the horizon. The frame of the panel does not include the top and bottom corner, but cuts a rectangular section of both places. In these two sections outside the panel is the last two paragraphs of Cueball's narrating:] Cueball (narrating): Until one day she bested her master Donald Knuth: So our lower bound here is O(n log n) Elaine: Nope. Got it in O(n log (log n)) Cueball (narrating): And left.

1337 Part 3

1337: Part 3

https://www.xkcd.com/343

https://www.explainxkcd.com/wiki/index.php/343:_1337:_Part_3

[Outside, Adrian Lamo is helping Elaine Roberts over a barbed wire fence.] It was the late 90's. Elaine crisscrossed the country with Adrian Lamo, the 'Homeless Hacker', learning to gain entry into systems both virtual and physical. Adrian Lamo: So you just throw a rug over the fence and... say, what is this place anyway? Roberts: Nowhere special. Lamo: ...Elaine, is this NSA Headquarters? Roberts: ...Look, I just want to see if they've broken RSA. [Inside, Lawrence Lessig is sitting at a table, Roberts is standing across the table swinging a knife.] She learned, from Lawrence Lessig, about the monstrosity that is U.S. Copyright Law. Roberts: So, how do we fix the system? Stab bad guys? Lessig: I'm starting something called "Creative Commons" Shink Elaine Roberts: I think we should stab bad guys... [Steve Jobs is lying up in his bed, Roberts is balancing while crouched on the foot of Jobs's bed.] She met with Steve Jobs to discuss the future of Apple. Roberts: Compression and bandwidth are changing everything. Jobs: Who are you? It's 3:00AM! Roberts: Apple should make a portable music player. Jobs: I'm calling the police. Roberts: Hey, idea — integrate it with a cell phone! [Scene has two of Elaine's activities. In one she is drumming, in the other she has an electric guitar on her shoulders, one hand on the frets. The other hand is holding a laptop by the touchpad.] She even, for a time, took up drumming, and helped start a movement among teen girls, a culture of self-taught female programmers and musicians, coding by day and rocking out by night— Roberts: Riot Prrl.

This is the third part of five in the " 1337 " series. The title 1337 is "L-eet," or "elite," using the Leet alphabet, a coding system used primarily on the internet (and on early text messaging system), meant to provide a bit of obfuscation to plain text both to make it harder to read and to show off in a creative way using in-group jargon. All comics in the series: This series was released on 5 consecutive days (Monday-Friday) and not over the usual Monday/Wednesday/Friday schedule. The comic is narrated by Cueball as seen in the previous comic, but that Cueball is not shown here, where the man drawn as Cueball is a real person: Adrian Lamo is a hacker known for being a threat analyst and has penetrated many corporate networks. As far as we know, he has not penetrated any government networks, so helping Elaine physically break into the NSA would probably inspire second thoughts. The use of a rug to cross the barbed wire fence is likely a reference to a scene in Fight Club , where the same method is used to break into a liposuction clinic. RSA (the algorithm) is an encryption algorithm that allows decryption using public keys . No efficient method to break RSA is known. [ citation needed ] But if the NSA knew any such method, it would be unlikely for them to admit that. However, the NSA have paid RSA (the company) to put a backdoor into one of their encryption schemes. Lawrence Lessig is a political activist focusing on copyright law and intellectual property, as well as a founding board member of Creative Commons . Steve Jobs was the two-time CEO of Apple Inc. In partnership with Steve Wozniak , he founded Apple. He oversaw Apple's return from near bankruptcy, the introduction of the original Macintosh, the iPod , the iPhone , and the iPad . But in the '90s, most of this had not happened yet. The comic is implying that it was Elaine, in fact, who planted those ideas in Jobs' mind (while perching on his bedpost, a nearly-impossible physical task for even a relatively small and light human being - such a stance is often depicted for gargoyles or fictional vampires, the latter of which are associated with nocturnal bedroom-invasions like this). Furthermore, Steve's reactions indicate that he was abruptly woken up by Elaine after she broke into his home and started a one-sided conversation with him. The final panel is a pun on the Riot grrrls - Riot grrrl is an underground feminist punk rock movement. This metamorphosizes in the hands of Randall into Riot Prrl - who presumably prefer to code in Perl . The real Riot Prrl is from Northampton and is into guerilla knitting . The title text may refer to the urban legend that leads petty criminals to ask each other "Are you a cop?" . The bottom line is that anyone who is capable of lying about breaking the RSA encryption algorithm, possibly including the "NSA guy," would be equally capable of lying about whether or not he is lying. [Outside, Adrian Lamo is helping Elaine Roberts over a barbed wire fence.] It was the late 90's. Elaine crisscrossed the country with Adrian Lamo, the 'Homeless Hacker', learning to gain entry into systems both virtual and physical. Adrian Lamo: So you just throw a rug over the fence and... say, what is this place anyway? Roberts: Nowhere special. Lamo: ...Elaine, is this NSA Headquarters? Roberts: ...Look, I just want to see if they've broken RSA. [Inside, Lawrence Lessig is sitting at a table, Roberts is standing across the table swinging a knife.] She learned, from Lawrence Lessig, about the monstrosity that is U.S. Copyright Law. Roberts: So, how do we fix the system? Stab bad guys? Lessig: I'm starting something called "Creative Commons" Shink Elaine Roberts: I think we should stab bad guys... [Steve Jobs is lying up in his bed, Roberts is balancing while crouched on the foot of Jobs's bed.] She met with Steve Jobs to discuss the future of Apple. Roberts: Compression and bandwidth are changing everything. Jobs: Who are you? It's 3:00AM! Roberts: Apple should make a portable music player. Jobs: I'm calling the police. Roberts: Hey, idea — integrate it with a cell phone! [Scene has two of Elaine's activities. In one she is drumming, in the other she has an electric guitar on her shoulders, one hand on the frets. The other hand is holding a laptop by the touchpad.] She even, for a time, took up drumming, and helped start a movement among teen girls, a culture of self-taught female programmers and musicians, coding by day and rocking out by night— Roberts: Riot Prrl.

1337 Part 4

1337: Part 4

https://www.xkcd.com/344

https://www.explainxkcd.com/wiki/index.php/344:_1337:_Part_4

[Elaine is sitting under tree on a grassy meadow typing on her laptop. Two trees are in the background where rolling hills goes to the horizon with a single cloud over the trees. Above the frame is text narrated by the Cueball from the first panel in the 2nd comic in the series:] Cueball (narrating): As time passed, Elaine intensified her hacking work, anonymously publishing exploit after exploit. [Elaine, wearing a backpack, is walking up to a door where her mom Mrs. Roberts is greeting her in the open door at the top of two steps. Above this very low panel's frame, there is more of Cueball's narration:] Cueball (narrating): To crack open proprietary hardware, she teamed up with one of the top experts in signal processing and data transferring protocols. Elaine: Hi, mom. Mrs. Roberts: Hello, dear. Did you have fun? [Elaine is lying on the floor with her laptop in front of her facing left with a charger on the floor further left. Mrs. Roberts is sitting to the right facing right on a chair working on her computer at a table. Cueball is still narrating above the frame:] Cueball (narrating): They were an unstoppable team. Elaine: I finished the CSS decryptor. Mrs. Roberts: Good, dear. I'll send it along to Jon. [Pan to the right where two men in black bowler hats arrive. Both hold briefcases - the first guy's reads RIAA, and the other guy's reads MPAA. Cueball's last narration in the comic is above the frame:] Cueball (narrating): And were eventually noticed. RIAA man: Game's over. MPAA man: You're coming with us. Briefcase 1: RIAA Briefcase 2: MPAA [Pan back left to the women. Mrs. Roberts stays in her chair sitting at her computer still typing, the screen emitting light, but Elaine has moved around to the right of the table and pulls out her folding knife and swings it open.] Elaine: Oh, are we? Mrs. Roberts: Now now, Elaine- Knife: Shink [Pan back right to the two men who simultaneously pull katana swords out of each of their briefcase, while still holding onto the handle with the other hand. When when opened like this, it causes two pieces of paper to fly out of the RIAA man's briefcase and a notebook to fly out of the MPAA man's briefcase.] Katanas: Shing [Pan back to the women. Mrs. Roberts continues to type on the laptop, a line going up from the keyboard indicating activity. Elaine still holds her open folding knife out, so the tip now touches the right frame of the panel.] Mrs. Roberts: Don't let them provoke you, dear. Man (off-panel): We don't want to hurt you, Ma'am. Mrs. Roberts: Don't by silly. Record company employees can't just go into houses and slice people up. [Pan back right to the two men who hold up the katana swords having left their briefcases closed on the floor. The closest RIAA man is holding a hand up, the other MPAA man is holding his sword in two hands and pointing it threateningly forward.] RIAA Man: Ah, so you haven't read the DMCA. MPAA Man: Title IV, Section 408: Authorization of Deadly Force. [A wide panel showing the whole scene with even Mrs. Robert now standing having just pushed her chair back, the computer inert. Elaine is bending in the knees, knife at the ready. Both bowler hat men, still holding their swords as before, but no hands up, have turned to look right back over their shoulder to see who speaks, as a voice comes from off-panel right.] Richard Stallman (off-panel): Hark! [The scene pans further right, so the two women are no longer in the panel, but Richard Stallman can now be seen with his wild beard and long hair and holding two katana swords, one in front of him and one over his head also pointing towards the two bowler hat med. They are standing normally, looking back at Stallman. The MPAA man nearest him holds a hand to his mouth as he speaks.] Richard Stallman: Cease this affront to freedom Richard Stallman: Or stand and defend yourselves! MPAA Man: Stallman!

This is the fourth part of five in the " 1337 " series. The title 1337 is "L-eet," or "elite," using the Leet alphabet, a coding system used primarily on the internet (and on early text messaging system), meant to provide a bit of obfuscation to plain text both to make it harder to read and to show off in a creative way using in-group jargon. All comics in the series: This series was released on 5 consecutive days (Monday-Friday, probably because he wanted to release comic 404 on april fools' day) and not over the usual Monday/Wednesday/Friday schedule. The comic is narrated by Cueball as seen in part 2, but that Cueball is not shown here, but still he is part of this comic series, and thus also this comic. In this part, Elaine Roberts returns to the second best hacker in the world (she being the best according to part 2): her mom Mrs. Roberts . Together, they are an unstoppable force, and they help out a guy called Jon with a CSS decryptor ( Content Scramble System , not to be confused with Cascading Style Sheets). This implies that Jon Lech Johansen 's DeCSS was written by Elaine. Jon Lech Johansen, also known as DVD Jon, is famous for DeCSS , a DVD decryption program that removes the copy protection from commercial DVDs. The Motion Picture Association of America , also known as the MPAA, was not amused. Both the MPAA and the Recording Industry Association of America (RIAA) use the Digital Millennium Copyright Act , shortened to DMCA, as a kind of brute club to silence "infringements" on their copyright. In a perfect world, the DMCA provides safe harbor protection to websites and consumers to make fair use of copyrighted content, while also affording copyright owners the ability to protect their works from being pirated. In this world, this means that any content protection system, no matter how weak and poorly executed, cannot be circumvented, and discussion of circumvention is illegal as well. This is not a perfect world, and in the end, the Roberts team is noticed. Two men with black bowler hats and briefcases with the abbreviations MPAA and RIAA show up at their house to arrest them. The two men look very much like Thomson and Thompson from The Adventures of Tintin , who are (bumbling) policemen/detectives who do not usually attempt violence or wield weapons more dangerous than a standard furled umbrella, but here it more likely depicts the Evil Organization Nebulous Evil Organization 's corporate variation upon the Men In Black. While Elaine is not ready to let them arrest her, she draws her knife, and they draw their katana swords out of their (way too short) briefcases. Mrs. Roberts says to her daughter that she should calm down, because it is illegal to slice people up in their own houses. However, the two men disagree and refer to the DMCA Title IV, Section 408: Authorization of Deadly Force. (There is actually no Title IV, Section 408 of the DMCA; Title IV ends with Section 407.) So now the two women are in lethal danger. But of course, Richard Stallman , founder of the GNU Project and stalwart defender of freedom and copyleft , cannot stand for this kind of repression of freedom. (In the real world, Stallman is not a swordsman, but he is always depicted with two katana swords in xkcd, first time was in 225: Open Source .) In keeping with the " Kill Bill " themes from earlier in the series, Randall imagines the conflict between Elaine/Stallman/Mrs. Roberts vs MPAA/RIAA agents as an action-packed katana battle, rather than the legal battle it would likely have been in real life. The title text is talking about a Linux -ism. In Linux (and all Unix derivatives), ~ is a symbol for a user's home directory (usually /home/<username> ). Presumably, "nomad" is Elaine's username. find is an application that recursively walks a filesystem, listing all files, and xargs shred takes those files and securely erases each one with pseudo-random data. This is different from simply deleting a file, which merely removes the pointer in the filesystem's record tables to the file's location on the hard disk. The latter can usually be recovered from. Secure delete, however, requires physically taking apart a disk and reading individual bits for remaining magnetic charge to attempt to reconstruct what was there. This means she was trying to permanently delete her and Elaine's files, presumably so the agents wouldn't have any proof of their hacking. Proprietary hardware is hardware (the electronics part rather than the software) created and used only by that company, as opposed to open hardware, which uses parts or chips common to everyone. Proprietary hardware used to be found in most gaming consoles and Apple/Mac devices, but that isn't as common now, since the cost of designing your own hardware is too expensive compared to using common chips. [Elaine is sitting under tree on a grassy meadow typing on her laptop. Two trees are in the background where rolling hills goes to the horizon with a single cloud over the trees. Above the frame is text narrated by the Cueball from the first panel in the 2nd comic in the series:] Cueball (narrating): As time passed, Elaine intensified her hacking work, anonymously publishing exploit after exploit. [Elaine, wearing a backpack, is walking up to a door where her mom Mrs. Roberts is greeting her in the open door at the top of two steps. Above this very low panel's frame, there is more of Cueball's narration:] Cueball (narrating): To crack open proprietary hardware, she teamed up with one of the top experts in signal processing and data transferring protocols. Elaine: Hi, mom. Mrs. Roberts: Hello, dear. Did you have fun? [Elaine is lying on the floor with her laptop in front of her facing left with a charger on the floor further left. Mrs. Roberts is sitting to the right facing right on a chair working on her computer at a table. Cueball is still narrating above the frame:] Cueball (narrating): They were an unstoppable team. Elaine: I finished the CSS decryptor. Mrs. Roberts: Good, dear. I'll send it along to Jon. [Pan to the right where two men in black bowler hats arrive. Both hold briefcases - the first guy's reads RIAA, and the other guy's reads MPAA. Cueball's last narration in the comic is above the frame:] Cueball (narrating): And were eventually noticed. RIAA man: Game's over. MPAA man: You're coming with us. Briefcase 1: RIAA Briefcase 2: MPAA [Pan back left to the women. Mrs. Roberts stays in her chair sitting at her computer still typing, the screen emitting light, but Elaine has moved around to the right of the table and pulls out her folding knife and swings it open.] Elaine: Oh, are we? Mrs. Roberts: Now now, Elaine- Knife: Shink [Pan back right to the two men who simultaneously pull katana swords out of each of their briefcase, while still holding onto the handle with the other hand. When when opened like this, it causes two pieces of paper to fly out of the RIAA man's briefcase and a notebook to fly out of the MPAA man's briefcase.] Katanas: Shing [Pan back to the women. Mrs. Roberts continues to type on the laptop, a line going up from the keyboard indicating activity. Elaine still holds her open folding knife out, so the tip now touches the right frame of the panel.] Mrs. Roberts: Don't let them provoke you, dear. Man (off-panel): We don't want to hurt you, Ma'am. Mrs. Roberts: Don't by silly. Record company employees can't just go into houses and slice people up. [Pan back right to the two men who hold up the katana swords having left their briefcases closed on the floor. The closest RIAA man is holding a hand up, the other MPAA man is holding his sword in two hands and pointing it threateningly forward.] RIAA Man: Ah, so you haven't read the DMCA. MPAA Man: Title IV, Section 408: Authorization of Deadly Force. [A wide panel showing the whole scene with even Mrs. Robert now standing having just pushed her chair back, the computer inert. Elaine is bending in the knees, knife at the ready. Both bowler hat men, still holding their swords as before, but no hands up, have turned to look right back over their shoulder to see who speaks, as a voice comes from off-panel right.] Richard Stallman (off-panel): Hark! [The scene pans further right, so the two women are no longer in the panel, but Richard Stallman can now be seen with his wild beard and long hair and holding two katana swords, one in front of him and one over his head also pointing towards the two bowler hat med. They are standing normally, looking back at Stallman. The MPAA man nearest him holds a hand to his mouth as he speaks.] Richard Stallman: Cease this affront to freedom Richard Stallman: Or stand and defend yourselves! MPAA Man: Stallman!

1337 Part 5

1337: Part 5

https://www.xkcd.com/345

https://www.explainxkcd.com/wiki/index.php/345:_1337:_Part_5

[The two men in black bowler hats (RIAA and MPAA agents as known from the previous comic) with their katanas are attacked by Elaine Roberts with her folding knife and Richard Stallman with his own two katanas. Elaine kicks the RIAA man to the left in the back of his leg, while Stallman jumps over the MPAA man to the right, flying high over him from right to left in a flying maneuver hitting his sword while hanging parallel to the ground above the man.] Elaine: Thanks, Stallman! Richard Stallman: 'Tis my pleasure. [Elaine stands to the left with her knife in one hand having folded it down again. Richard Stallman stands between the two men with bowler hats who are now lying on the floor on either side of him, each with one of Stallman's swords pointing at their throat. Stallman has both arms fully stretched towards them as he looks straight out of the panel. The left (RIAA) man lies flat on his back, his hat and katana lying behind him. The right (MPAA) man is sitting on his knee leaning as far back as he can, since the sword is almost touching the skin on his throat. He wears his hat, but the sword lies behind him, out of reach, even though he is leaning back on one hand close to it. To the far right, a rope comes down from the top of the panel, falling down on the ground so a section of it stretches even farther right in the picture. Down this rope comes a man with googles and a red cape, which is black on the inside. This is Cory Doctorow. He holds onto the rope with two hands, one over one just under his head.] Elaine: So, wait - how did you know we were in trouble? Richard Stallman: My friend here was tracking these thugs from his balloon. Richard Stallman: He called me and I thought I'd stop by. Cory Doctorow: -Hi! Cory Doctorow: Cory Doctorow - It's a pleasure to meet you. [Elaine has shifted the knife to the other hand. Richard Stallman has moved to the left of the RIAA man, so both bowler hat men are between him and Cory Doctorow. Stallman still points his sword in their direction, but they are lowered. The RIAA man closest to him has picked up his hat in one hand and reaches for his sword with the other hand. The MPAA man now lies on his back, one arm up, leaning on the other. His sword is gone. It does not seem like Doctorow could have taken it. Behind him, Doctorow has reached the ground, the rope hanging behind him. He points left.] Elaine: Balloon? Richard Stallman: Aye. They're up there constructing something called a "Blogosphere." Cory Doctorow: Yup! It's twenty kilometers up, just above the tag clouds. [The scene is contracted, so to the left, Mrs. Roberts at her desk with her chair and laptop becomes visible (from the previous comic). This without the other people has moved closer. She still types as her son Little Bobby Tables enters and lifts a hand in his mother's direction. He is drawn as a child version of Cueball. Elaine has put the knife away and looks at Richard Stallman, who now stands straight looking at her with the swords crossed in front of his legs. Behind him, just right of the rope hanging down, Cory Doctorow lifts one of the agents up by the throat while looking right and talking to him. The other agent has left the panel. The one he holds has his hat but no sword.] Little Bobby Tables: Mom, I'm hungry. Mrs. Roberts: Hush, I'm coding. You ate yesterday. Richard Stallman: You know, Roberts, GNU could use a good coder like you. Ever thought of joining us? Elaine: Maybe someday. Right now I've got an industry to take down. Elaine: Music doesn't need these assholes. Cory Doctorow: Begone, And never darken our comment threads again! [Zoom in on Elaine, Richard Stallman, and Cory Doctorow. She stand straight looking at Stallman, who faces towards her swords now on his back crossed. Doctorow is also facing her and holds out both arms towards her. The rope is now outside the panel, as are both bowler hat men.] Richard Stallman: Well, you won't fix the industry with random exploits. You need to encourage sharing in the public mind. Doctorow: Hey; With your music and coding backgrounds, you should get into building better P2P systems. [The final panel is only a third of the length of the previous panel. The three are still in the panel, but they have moved and are also drawn somewhat smaller. Elaine still faces them right, but now Cory Doctorow is in front of Richard Stallman's swords as before. All have their arms down.] Elaine: What? Straight-up piracy? Cory Doctorow: Sure - have you ever considered it? You'd make a wonderful dread pirate, Roberts. [To the right of the final panel is a two-column epilogue narrated by Cueball as seen in part 2. It is split into three paragraphs and a "signature." The caption above is centered over the two columns.] E pilogu e Cueball (narrating): Elaine shared her ideas with Bram Cohen, who went on to develop BitTorrent. Mrs. Roberts spends her time developing for Ubuntu, and defacing the websites of people who make "your mom" jokes to her daughter. Elaine still stalks the net. She joins communities, contributes code or comments, and moves on. And if, late at night, you point a streaming audio player at the right IP at the right time - you can hear her rock out. ~Happy Hacking.~

This is the fifth and last part of five in the " 1337 " series. The title 1337 is "L-eet," or "elite," using the Leet alphabet, a coding system used primarily on the internet (and on other early text messaging systems), meant to provide a bit of obfuscation to plain text both to make it harder to read (and potentially 'grep' for incriminating terms) and to show off in a creative way using in-group jargon. All comics in the series: This series was released on 5 consecutive days (Monday-Friday, probably because he wanted to release comic 404 on april fools' day) and not over the usual Monday/Wednesday/Friday schedule. The comic is narrated by Cueball as seen in part 2 comic, but that Cueball is not shown here, but still he is part of this comic series, and thus also this comic, as he narrates the epilogue. Richard Stallman is the ardent defender of freedom and believer in copyleft ; he also founded the GNU Project . (He is not really a sword fighter but is always depicted with swords when featured in xkcd , which is in this series and in 225: Open Source ). In the previous part, he came to the rescue of Mrs. Roberts and her Daughter Elaine Roberts . Stallman and Elaine quickly overpower the two enemies with black bowler hats who represent the Motion Picture Association of America (MPAA) and the Recording Industry Association of America (RIAA), use the Digital Millenium Copyright Act who had found out about the Roberts hacking. Just when the two men have been defeated, Elaine asks how Stallman knew they where in trouble, and he tells it was his friend who told him about it. Climbing down a rope from the sky, the friend enters with a red cape and goggles. It turns out it is Cory Doctorow , a blogger, journalist, and science fiction author who serves as co-editor of the weblog Boing Boing . He is an activist in favor of liberalizing copyright laws and a proponent of the Creative Commons organization. He does not really travel around in a balloon or (usually) wear a red cape, but Randall introduced this idea in 239: Blagofaire and has continued it in later comics featuring Cory Doctorow . So he is climbing down from his balloon. He uses the balloon to construct the Blogosphere , which is a name used to refer to all blogs on the Internet, many of which frequently link to and refer to other blogs. Here, the Stallman character talks about it as though Cory Doctorow actually constructs it, as if it were a portion of the atmosphere 20 km up over the tag clouds. Blogs often label posts with keywords, known as tags. A tag cloud is a way of displaying the tags on a site where the more common tags appear in larger type than less-common ones. It has no relationship to actual water vapor clouds in the sky, but in the comic, the Doctorow character suggests that tag clouds are actually in the air, below the new blogosphere. At this point we see that Mrs. Roberts is still programming while this fight and discussion take place. Her son Little Bobby Tables comes and tells her he is hungry, but she tells him that she does not have time when she is coding, and that he ate yesterday. It seems that he is still a kid, even though it must have been some years since the young Elaine left and grew up. However, she may still be a very young adult, in which case her little brother could still be shorter than his mom (we see in Part 2 that, from age 11, she studied with Donald Knuth for four years, making her 15 when she left. However, it is not clear how long she was away from home after that). Stallman gives Elaine a proposal to join GNU as a coder. GNU is supposed to be the pinnacle of free software; an operating system with no restriction, allowing the user to modify and customize anything they want about the computer. Stallman likely wants Elaine for her coding abilities, similar devotion to free software, and use her reputation as a hacker and open source pioneer to spread the word and further his project. This may also be a reference to the infamous "Free Software Song", [1] sung by Stallman in which he exhorts hackers to "join us now and share the software." But she is not ready yet, as she wished to take down the industry of MPAA and RIAA as Music doesn't need these assholes. In the meantime, Cory Doctorow throws the bowler hat guys out and orders them never to "darken our comment threads again." Stallman is against her idea of going for straight war with the industry, and suggests that she help encourage sharing in the public mind. And then Doctorow chimes in with a suggestion that she has the ability to build better P2P systems, to which she asks if they mean straight up piracy. And this leads up to the punch line of the series, when Doctorow says she (i.e. "[Ms] Roberts"), would make a wonderful Dread Pirate! Peer-to-peer, often abbreviated P2P, is a network system where tasks are partitioned between participants with equal privileges, in contrast with the client-server model, where the client makes requests and the server provides service. A common example of a peer-to-peer system is the BitTorrent file-sharing protocol, which is often (mis)used for distribution of pirated software and media. The Dread Pirate Roberts is a fictional character from the book and movie The Princess Bride . Roberts is the most feared pirate on the seas. But, "Dread Pirate Roberts" is merely a title that has been passed down as previous "Roberts" have gained enough money (from piracy) to retire comfortably. Westley, one of the main characters from The Princess Bride, becomes the Dread Pirate after being taken prisoner by the preceding Pirate Roberts. It is anyone's guess whether the entire 5-comic story, starting from the choice of Mrs. Roberts' name, began as just a lead-up to this one joke. At the end of the movie, Inigo Montoya has won the vengeance he has sought all his life, and expresses to Westley that he doesn't know what to do next. Westley suggests Montoya succeed him as Roberts, saying, "Have you ever considered piracy? You'd make a wonderful Dread Pirate Roberts." Cory Doctorow's line in the comic therefore mimics that line from the movie. Silk Road was an online black market designed to allow criminals to trade in drugs, guns, and other illegal items, run by a person also using the pseudonym Dread Pirate Roberts. However, this black market did not exist until four years after this comic was published. In the epilogue, several items of interest are revealed about the Roberts’ later lives. Elaine shared her ideas with Bram Cohen , who went on from that to found BitTorrent , a distributed method of downloading files. People can and do use BitTorrent both for lawful file downloads and also for sharing media files unlawfully. Its distributed nature, where someone does not download a file from just one other computer but rather in many pieces from many other computers with the same file, makes it more difficult for record and movie industry groups to police, and therefore a person with Elaine's motivations might be interested in helping design such a system. Mrs. Roberts developed for Ubuntu , which is probably the most well known distribution of GNU/ Linux . A GNU/Linux distribution (often referred to simply as "Linux") is any operating system that is based on GNU software and the Linux kernel . She also went after any website (defacing them) that made Your mom jokes about her daughter. To deface a website is like putting up graffiti or tearing down signs; she likely replaces the URL's content from the original site to another image, text box, or other message as revenge. This is a recurring theme on xkcd. Defacing websites is generally considered a low-level hacking activity, generally carried out by script kiddies using pre-packaged exploits rather than by highly skilled hackers like Elaine. Finally a bit more info is given on how Elaine continues her fight: she joins random communities, helps with code, and mysteriously moves on. Sometimes she streams her music live on an IP address, and if you happen to find one of these with a streaming audio player, you can hear her rock out (a reference to her music career mentioned at the end of the third part). The final phrase "Happy Hacking" often accompanies an autograph from Richard Stallman. The title text is likely referring to the argument over Digital Rights Management , or DRM-locked content. These so-called 'DRM wars' are concerned about how DRM restricts the freedoms of people who buy them legitimately, and how it restricts creativity and innovation on the Internet. A large part of the debate is digital music, or music you would buy and download on the Internet through sites like Amazon or iTunes. The title text states that the DRM wars will end in the next decade or so, and we are living through very exciting times as we can see these wars unfold and eventually end. In 2009, iTunes did remove DRM from any music they sold, which was a huge milestone at the time. Due to the rise in music streaming services (all of which use DRM to keep clients from downloading their songs) in the mid- to late 2010s, this achievement has been made void again. [The two men in black bowler hats (RIAA and MPAA agents as known from the previous comic) with their katanas are attacked by Elaine Roberts with her folding knife and Richard Stallman with his own two katanas. Elaine kicks the RIAA man to the left in the back of his leg, while Stallman jumps over the MPAA man to the right, flying high over him from right to left in a flying maneuver hitting his sword while hanging parallel to the ground above the man.] Elaine: Thanks, Stallman! Richard Stallman: 'Tis my pleasure. [Elaine stands to the left with her knife in one hand having folded it down again. Richard Stallman stands between the two men with bowler hats who are now lying on the floor on either side of him, each with one of Stallman's swords pointing at their throat. Stallman has both arms fully stretched towards them as he looks straight out of the panel. The left (RIAA) man lies flat on his back, his hat and katana lying behind him. The right (MPAA) man is sitting on his knee leaning as far back as he can, since the sword is almost touching the skin on his throat. He wears his hat, but the sword lies behind him, out of reach, even though he is leaning back on one hand close to it. To the far right, a rope comes down from the top of the panel, falling down on the ground so a section of it stretches even farther right in the picture. Down this rope comes a man with googles and a red cape, which is black on the inside. This is Cory Doctorow. He holds onto the rope with two hands, one over one just under his head.] Elaine: So, wait - how did you know we were in trouble? Richard Stallman: My friend here was tracking these thugs from his balloon. Richard Stallman: He called me and I thought I'd stop by. Cory Doctorow: -Hi! Cory Doctorow: Cory Doctorow - It's a pleasure to meet you. [Elaine has shifted the knife to the other hand. Richard Stallman has moved to the left of the RIAA man, so both bowler hat men are between him and Cory Doctorow. Stallman still points his sword in their direction, but they are lowered. The RIAA man closest to him has picked up his hat in one hand and reaches for his sword with the other hand. The MPAA man now lies on his back, one arm up, leaning on the other. His sword is gone. It does not seem like Doctorow could have taken it. Behind him, Doctorow has reached the ground, the rope hanging behind him. He points left.] Elaine: Balloon? Richard Stallman: Aye. They're up there constructing something called a "Blogosphere." Cory Doctorow: Yup! It's twenty kilometers up, just above the tag clouds. [The scene is contracted, so to the left, Mrs. Roberts at her desk with her chair and laptop becomes visible (from the previous comic). This without the other people has moved closer. She still types as her son Little Bobby Tables enters and lifts a hand in his mother's direction. He is drawn as a child version of Cueball. Elaine has put the knife away and looks at Richard Stallman, who now stands straight looking at her with the swords crossed in front of his legs. Behind him, just right of the rope hanging down, Cory Doctorow lifts one of the agents up by the throat while looking right and talking to him. The other agent has left the panel. The one he holds has his hat but no sword.] Little Bobby Tables: Mom, I'm hungry. Mrs. Roberts: Hush, I'm coding. You ate yesterday. Richard Stallman: You know, Roberts, GNU could use a good coder like you. Ever thought of joining us? Elaine: Maybe someday. Right now I've got an industry to take down. Elaine: Music doesn't need these assholes. Cory Doctorow: Begone, And never darken our comment threads again! [Zoom in on Elaine, Richard Stallman, and Cory Doctorow. She stand straight looking at Stallman, who faces towards her swords now on his back crossed. Doctorow is also facing her and holds out both arms towards her. The rope is now outside the panel, as are both bowler hat men.] Richard Stallman: Well, you won't fix the industry with random exploits. You need to encourage sharing in the public mind. Doctorow: Hey; With your music and coding backgrounds, you should get into building better P2P systems. [The final panel is only a third of the length of the previous panel. The three are still in the panel, but they have moved and are also drawn somewhat smaller. Elaine still faces them right, but now Cory Doctorow is in front of Richard Stallman's swords as before. All have their arms down.] Elaine: What? Straight-up piracy? Cory Doctorow: Sure - have you ever considered it? You'd make a wonderful dread pirate, Roberts. [To the right of the final panel is a two-column epilogue narrated by Cueball as seen in part 2. It is split into three paragraphs and a "signature." The caption above is centered over the two columns.] E pilogu e Cueball (narrating): Elaine shared her ideas with Bram Cohen, who went on to develop BitTorrent. Mrs. Roberts spends her time developing for Ubuntu, and defacing the websites of people who make "your mom" jokes to her daughter. Elaine still stalks the net. She joins communities, contributes code or comments, and moves on. And if, late at night, you point a streaming audio player at the right IP at the right time - you can hear her rock out. ~Happy Hacking.~

Diet Coke+Mentos

Diet Coke+Mentos

https://www.xkcd.com/346

https://www.explainxkcd.com/wiki/index.php/346:_Diet_Coke%2BMentos

[Cueball and his friend are sitting on the ground, with a bottle of Diet Coke between them, and Cueball appears to be putting mentos into the bottle.] Cueball: This is the coolest thing. You just drop the Mentos in the Diet Coke... Friend: Uh huh. [Diet Coke starts to fizzle.] Cueball: Give it a moment... [Someone teleports into frame in a magic puff. Cueball's arms are raised, with a package of Mentos in one hand.] POOF Friend: D-Dad? Dad: I'm back, son. We can be a family again.

This comic's premise is a reference to the phenomenon of dropping Mentos into a bottle of a carbonate beverage to create a geyser of said beverage . During 2007, a large number of videos depicting this phenomenon floated around the Internet. Cueball wants to show this phenomenon to his friend, because it's "the coolest thing". However, instead of achieving the standard result, a geyser of Diet Coke, the friend's father magically appears (presumably from the dead or from abandonment). An alternative interpretation is that the friend's father is resurrected/returned in an event unrelated to the geyser, undermining the geyser's coolness. The title text shows that Randall considers (or at least then considered) this trick to be as cool as mixing corn starch and water to make a non-Newtonian fluid that reacts wildly with vibrations and impact. [Cueball and his friend are sitting on the ground, with a bottle of Diet Coke between them, and Cueball appears to be putting mentos into the bottle.] Cueball: This is the coolest thing. You just drop the Mentos in the Diet Coke... Friend: Uh huh. [Diet Coke starts to fizzle.] Cueball: Give it a moment... [Someone teleports into frame in a magic puff. Cueball's arms are raised, with a package of Mentos in one hand.] POOF Friend: D-Dad? Dad: I'm back, son. We can be a family again.

Brick Archway

Brick Archway

https://www.xkcd.com/347

https://www.explainxkcd.com/wiki/index.php/347:_Brick_Archway

[An inset panel to the left shows Cueball getting ready to throw a tennis ball upward.] [Cueball lies on the ground, underneath the titular brick archway, next to two halves of a brick. A pool of blood is coming from his head. Dust falls from the place in the archway where the he knocked the brick from with the tennis ball. The ball, meanwhile, has rolled about a meter away.] "Breakout" is a stupid game.

Breakout is a video game first created in 1976, and since then it has gained much popularity and has been recreated in many different versions. In the game, the player controls a horizontal 'bat' at the bottom of the screen to make it move left or right. Above it are several layers of bricks that are destroyed when hit by the ball. The ball is not affected by gravity and will float around, bouncing off the walls, bricks, and the bat. The aim of the game is to keep the ball from touching the bottom of the screen (by deflecting it with the bat) long enough for the ball to hit and destroy all of the bricks. Cueball 's approach to the game is to actually stand underneath a brick archway and throw a tennis ball at the structure above him in an attempt to destroy the bricks. Naturally, the physics in the game don't work in real life, [ citation needed ] and the aftermath of Cueball's actions is that one of the bricks in the archway comes loose and falls onto Cueball's head, causing possibly fatal damage. The sentence at the bottom of the comic points out the illogical nature of the game when compared to real life. The title text relates to a programmable calculator from the late 1990s that could have a Breakout -like game easily programmed into. This calculator, and others like it, were a requirement in many high school advanced math classes in the United States after the early 1990s, despite costing over $100. Randall speculates that, given the amount of distraction this simple game provided him back then, he would not be able to focus on study at all with modern technical instruments like laptops using wireless LANs . [An inset panel to the left shows Cueball getting ready to throw a tennis ball upward.] [Cueball lies on the ground, underneath the titular brick archway, next to two halves of a brick. A pool of blood is coming from his head. Dust falls from the place in the archway where the he knocked the brick from with the tennis ball. The ball, meanwhile, has rolled about a meter away.] "Breakout" is a stupid game.

Close to You

Close to You

https://www.xkcd.com/348

https://www.explainxkcd.com/wiki/index.php/348:_Close_to_You

[Cueball is singing to Megan, who has wiggly lines and unkempt hair. Musical notes appear around Cueball's words.] Cueball: Why do birds suddenly appear [Still singing.] Cueball: Every tiiiime you are neeear [Cueball stops singing. He looks up.] Cueball: Wait, are those turkey vultures? [Cueball turns to Megan.] Cueball: Okay, listen, are you a zombie? Megan: Hurrghhh...

This is Randall's version of the popular Carpenters song, " (They Long to Be) Close to You ." The actual first verse goes like this: Why do birds suddenly appear Every time you are near? Just like me, they long to be Close to you In this parody, the reason birds suddenly appear whenever the girl is near is because the girl is a zombie, and those are turkey vultures , carrion birds that prey on the flesh of dead bodies. The title text is joking about couples not discussing their relationship before their wedding, as is seen here . [Cueball is singing to Megan, who has wiggly lines and unkempt hair. Musical notes appear around Cueball's words.] Cueball: Why do birds suddenly appear [Still singing.] Cueball: Every tiiiime you are neeear [Cueball stops singing. He looks up.] Cueball: Wait, are those turkey vultures? [Cueball turns to Megan.] Cueball: Okay, listen, are you a zombie? Megan: Hurrghhh...

Success

Success

https://www.xkcd.com/349

https://www.explainxkcd.com/wiki/index.php/349:_Success

[Four full-width panels arranged vertically, each with a label for number of hours elapsed, with a title above the stack of panels.] Title: As a project wears on, standards for success slip lower and lower. [Megan is standing behind Cueball, watching him as he sits at a desk working on a desktop computer on the desk.] Label: 0 hours Cueball: Okay, I should be able to dual-boot BSD soon. [Cueball is on the floor fiddling with the open tower in front of him. Megan is not shown in the panel, but may be off-panel unless Cueball is talking to himself.] Label: 6 hours Cueball: I'll be happy if I can get the system working like it was when I started. [Cueball is standing in front of the computer, which now has a laptop plugged into the tower. Megan is still not shown in the panel, but may be off-panel again.] Label: 10 hours Cueball: Well, the desktop's a lost cause, but I think I can fix the problems the laptop's developed. [Cueball and Megan are swimming in the sea; an island and a beach can be seen in the distance.] Label: 24 hours Cueball: If we're lucky, the sharks will stay away until we reach shallow water. Megan: If we make it back alive, you're never upgrading anything again.

This comic refers to a common experience in which attempts to improve or change something can get you into even worse trouble, and where just getting back to the state at which you started becomes an arduous or even impossible task. Here, this idea is taken to a ridiculously (and amusingly) extreme level, where the attempt to install an operating system snowballs into ever more complicated problems, resulting in Cueball and Megan somehow literally getting themselves in deep water. The OS they are trying to install is OpenBSD , an open source Unix operating system that, like some other Unix variants, is notoriously difficult to install and configure correctly, especially on home desktops with less common hardware profiles, and especially compared with the more popular Windows operating system. The title text is a reference to OpenBSD's premium on security. For a time, their slogan was "Five years without a remote [security] hole in the default install!" This was eventually changed to "Only two remote holes in the default install, in a heck of a long time!" That their only standing security issue would be shark attacks is effectively an acknowledgement that any attempts to install the OS will only lead to getting stranded in the middle of the ocean. This comic was referenced later in 1350: Lorenz . Trying to install BSD was also referenced in 518: Flow Charts . The last panel in 1912: Thermostat may explain how this comic ended. Later, another possible reason to ending up in the ocean was given in 2083: Laptop Issues . This comic follows a similar storyline to 530: I'm An Idiot and 1518: Typical Morning Routine , as Cueball and Hairy encounter an issue and attempt proceedingly more absurd solutions to the issue. [Four full-width panels arranged vertically, each with a label for number of hours elapsed, with a title above the stack of panels.] Title: As a project wears on, standards for success slip lower and lower. [Megan is standing behind Cueball, watching him as he sits at a desk working on a desktop computer on the desk.] Label: 0 hours Cueball: Okay, I should be able to dual-boot BSD soon. [Cueball is on the floor fiddling with the open tower in front of him. Megan is not shown in the panel, but may be off-panel unless Cueball is talking to himself.] Label: 6 hours Cueball: I'll be happy if I can get the system working like it was when I started. [Cueball is standing in front of the computer, which now has a laptop plugged into the tower. Megan is still not shown in the panel, but may be off-panel again.] Label: 10 hours Cueball: Well, the desktop's a lost cause, but I think I can fix the problems the laptop's developed. [Cueball and Megan are swimming in the sea; an island and a beach can be seen in the distance.] Label: 24 hours Cueball: If we're lucky, the sharks will stay away until we reach shallow water. Megan: If we make it back alive, you're never upgrading anything again.

Network

Network

https://www.xkcd.com/350

https://www.explainxkcd.com/wiki/index.php/350:_Network

[Megan looking at a large screen with many green and red squares. The squares have writing in them and lines connecting them.] [Side view. The screen is a huge LCD connected to a wireless router.] Cueball: Pretty, isn't it? Megan: What is it? Cueball: I've got a bunch of virtual Windows machines networked together, hooked up to an incoming pipe from the net. They execute email attachments, share files, and have no security patches. Cueball: Between them they have practically every virus. Cueball: There are mail trojans, warhol worms, and all sorts of exotic polymorphics. A monitoring system adds and wipes machines at random. The display shows the viruses as they move through the network. Growing and struggling. [Cueball walks past the girl and touches the monitor.] Megan: You know, normal people just have aquariums. Cueball: Good morning, Blaster. Are you and W32.Welchia getting along? Cueball: Who's a good virus? You are! Yes, you are!

Cueball shows off his virtual fishtank of virus-infected virtual Windows machines to Megan . The machines nominally have mail trojans , Warhol worms , all sorts of polymorphic viruses , and explicitly Blaster and w32.welchia . Cueball relates to the viruses as though they are fish, and hopes that they are all getting along together nicely. This is because part of welchia's payload was to remove the Blaster Worm , effectively destroying it. A computer network or data network is a telecommunications network that allows computers to exchange data. In computer networks, networked computing devices exchange data with each other using a data link. The connections between nodes are established using either cable media or wireless media. The best-known computer network is the Internet. Network computer devices that originate, route, and terminate the data are called network nodes. Nodes can include hosts such as personal computers, phones, and servers as well as networking hardware. Two such devices can be said to be networked together when one device is able to exchange information with the other device, whether or not they have a direct connection to each other. Computer networks differ in the transmission medium used to carry their signals, the communications protocols to organize network traffic, the network's size, topology, and organizational intent. It would be possible to set up a virtual fish tank as described. The main issue would be to make sure that you don't accidentally let anything escape from the fish tank. Consider it like a smallpox lab. Also, some viruses are quite malicious [ citation needed ] and will prevent a computer from running normally, or at all. An aquarium of dead computers would not be very interesting to watch. [ citation needed ] The first part of the title text refers to the difficulty viruses have in the common doomsday threat of "disabling the internet" as a whole, although SQL Slammer had some brief success. The second part of the title text indicates that Randall believes A) that Linux and Mac OS X are inherently less vulnerable to virus attacks than Windows, and B) that Windows will become less important and disappear, so the virus writers had better get their act together soon. It is not certain how justified this opinion is. Fifteen years after this comic was written, Windows still dominates the desktop, and Linux and OS X are not that much harder to attack with viruses. A side issue is the wild growth in 'smart devices' connected to the internet, powered by non-traditional operating systems such as iOS and Android. Desktop operating systems such as Windows, Linux, and OS X are all becoming less relevant (although note that Android is based on the Linux kernel and iOS is based on OS X), so both the operating system war and the struggle against computer viruses are still "anyone's game." A similar system to the one described by this comic was available online at http://wecan.hasthe.technology . It was last reported to be available online on June 29, 2014, but is no longer available. Instead of executing email attachments, the 7 VMs ran files uploaded via the site by the public, making it more of a public playground aquarium than a private fish tank. Instead of wiping machines at random, each VM runs a virus scanner every 24 hours. [Megan looking at a large screen with many green and red squares. The squares have writing in them and lines connecting them.] [Side view. The screen is a huge LCD connected to a wireless router.] Cueball: Pretty, isn't it? Megan: What is it? Cueball: I've got a bunch of virtual Windows machines networked together, hooked up to an incoming pipe from the net. They execute email attachments, share files, and have no security patches. Cueball: Between them they have practically every virus. Cueball: There are mail trojans, warhol worms, and all sorts of exotic polymorphics. A monitoring system adds and wipes machines at random. The display shows the viruses as they move through the network. Growing and struggling. [Cueball walks past the girl and touches the monitor.] Megan: You know, normal people just have aquariums. Cueball: Good morning, Blaster. Are you and W32.Welchia getting along? Cueball: Who's a good virus? You are! Yes, you are!

Trolling

Trolling

https://www.xkcd.com/351

https://www.explainxkcd.com/wiki/index.php/351:_Trolling

[Black Hat and Cueball are in Rick Astley's yard, hacking into his cable TV connection and replacing the signal. Rick Astley is sitting in a chair in his house, watching TV.] TV: CNN has obtained this exclusive footage of the riot-torn-- *CZZZHT* ♫ Never gonna give you up... ♪ Rick Astley: What the hell? [Caption below the frame:] GREAT MOMENTS in TROLLING: Rick Astley is successfully Rickrolled

The term Trolling is used to describe provocative, destructive, or annoying behavior on the Internet . Especially common are Internet pranks of the bait-and-switch type, an example of which is Rickrolling . It involves placing a link that is supposed to contain interesting or funny material, but instead directs to the music video of the 1987 Rick Astley song Never Gonna Give You Up . The prank first occurred in May 2007 on the popular imageboard 4chan and has since become a widespread internet meme . The comic has Black Hat and Cueball digging into the ground and splicing Black Hat's computer into the TV cables of Rick Astley 's house. They are feeding the video of Never Gonna Give You Up into Astley's TV signal, who can be seen sitting in his living room and wondering why CNN has been replaced by his own video. The act of Rickrolling Rick Astley himself is declared to be a "great moment in trolling". The title text mentions Goatse.cx (pronounced goat sex ), a former shock website that was used in a similar prank. People clicking on the feigned link would instead see the disturbing picture of a practitioner of anal stretching. The title text suggests that Black Hat and Cueball somehow made the (unknown) founder of the site click on an even more shocking link, or possibly put him in the personal presence of anal stretching. Also note that the comic image itself is itself a Rickroll. Anyone curious enough as to why their mouse pointer became the selection icon to click on the comic (on the original xkcd page ) would find themselves watching "Never Gonna Give You Up." Rick Astley was actually Rickrolled on reddit ( at r/pics ) on June 17th, 2020. [Black Hat and Cueball are in Rick Astley's yard, hacking into his cable TV connection and replacing the signal. Rick Astley is sitting in a chair in his house, watching TV.] TV: CNN has obtained this exclusive footage of the riot-torn-- *CZZZHT* ♫ Never gonna give you up... ♪ Rick Astley: What the hell? [Caption below the frame:] GREAT MOMENTS in TROLLING: Rick Astley is successfully Rickrolled

Far Away

Far Away

https://www.xkcd.com/352

https://www.explainxkcd.com/wiki/index.php/352:_Far_Away

[Cueball hugging Megan in the messenger window of an early Microsoft Windows version.] Cueball: Meh. Cueball: Some nights, typing "*hug*" just doesn't cut it.

Cueball and Megan are in a long-distance relationship ; in order to overcome the distance that separates them, they're keeping in touch with an instant messenger. Because their contact is limited to text, they have to write out the actions they wish to enact. Cueball is frustrated with the limitations of these place-holding phrases and longs for physical contact, going so far as to imagine himself hugging Megan in the messenger window. In the title text, Cueball suggests that, sometimes, the only way to end his frustration is to travel across the country and see her face-to-face. [Cueball hugging Megan in the messenger window of an early Microsoft Windows version.] Cueball: Meh. Cueball: Some nights, typing "*hug*" just doesn't cut it.

Python

Python

https://www.xkcd.com/353

https://www.explainxkcd.com/wiki/index.php/353:_Python

[A Cueball-like friend is talking to Cueball, who is floating in the sky.] Friend: You're flying! How? Cueball: Python! Cueball: I learned it last night! Everything is so simple! Cueball: Hello world is just print "Hello, World!" Friend: I dunno... Dynamic typing? Whitespace? Cueball: Come join us! Programming is fun again! It's a whole new world up here! Friend: But how are you flying? Cueball: I just typed 'import antigravity' Friend: That's it? Cueball: ...I also sampled everything in the medicine cabinet for comparison. Cueball: But I think this is the python.

Python is a programming language designed specifically to make it easy to write clear, readable programs. Flying is often used as a metaphor for freedom and ease, and here Randall shows Cueball literally flying in response to using Python. A "Hello, World!" program is a very simple program that prints the phrase "Hello, World!", used in textbooks to illustrate a given programming language. While this sounds simple, it can be nontrivial in some programming languages where you need to explicitly import a library that contains the print function (for instance, in C you need to begin with #include < stdio.h > ) or do complicated things with classes and variables (see the Java "Hello, World!" for one example). Python doesn't need any of that: print("Hello, world!") (or in Python 2, print "Hello, world!" ) really is all you need to do. Dynamic typing and significant whitespace are two controversial features of Python, which make some people—like Cueball's friend—hesitant to use the language. Dynamic typing means that variables do not have types (like "list of short integers" or "a bunch of letters"); any value of any type can be placed in any variable. Dynamic typing allows for more flexible languages, but it means that certain kinds of errors (like trying to subtract a letter from a number) can't be caught until a program is run, and some people think this is too dangerous for the tradeoff to be acceptable. Whitespace is a string of invisible text characters, like spaces or tabs. In programming, blocks of code controlled by a statement are usually indented under that statement. Most languages require you to use braces ( {…} ) or special keywords ( BEGIN…END ) to delimit these blocks; in Python, the indentation itself is the delimiter. Many Python programmers find that this makes code more readable, but many other programmers find it too "magical" and don't trust it. Classes, functions, and constants in Python are packed into modules. To use a module, you write " import module " at the top of your source file (you can do this anywhere in the file, but it's usually at the top so you can use the module throughout the code). Python comes with a very powerful standard library of modules to do everything from parsing XML to comparing two sets of files for differences, and new modules can be easily installed from the PyPI repository, which has more than 79,000 more to choose from (as of April 2016). Cueball can fly because he imported the antigravity module. Python still works for Cueball in 482: Height . In the final panel, Cueball admits that his ability to fly may actually be because he has "sampled everything in the medicine cabinet," though he's sure it is the Python anyway. An implication of this is that ingesting everything in the medicine cabinet has given him the feeling of freedom and ease that "flying" represents - or that he is hallucinating himself flying and having a conversation with the other character about it. Here, the metaphor of "feeling like you're flying" while using Python is transformed back from being literal (Cueball is actually flying) to being metaphorical (Randall feels like he is flying because Python is so easy to use... or because he had too many strange drugs). Perl , mentioned in the title text, is another programming language with the same target audience as Python, as both are high-level , general-purpose , interpreted , dynamic programming languages . However they strongly oppose each other in their language design: Since he has discovered Python, Randall doesn't like Perl anymore, probably because its syntax is less consistent or perhaps due to his problems with Regular expressions . What God has to say about Randall's renunciation of Perl has not yet been documented. [A Cueball-like friend is talking to Cueball, who is floating in the sky.] Friend: You're flying! How? Cueball: Python! Cueball: I learned it last night! Everything is so simple! Cueball: Hello world is just print "Hello, World!" Friend: I dunno... Dynamic typing? Whitespace? Cueball: Come join us! Programming is fun again! It's a whole new world up here! Friend: But how are you flying? Cueball: I just typed 'import antigravity' Friend: That's it? Cueball: ...I also sampled everything in the medicine cabinet for comparison. Cueball: But I think this is the python.

Startling

Startling

https://www.xkcd.com/354

https://www.explainxkcd.com/wiki/index.php/354:_Startling

[Cueball sits silently in front of his computer.] [Text block:] I still do this every few months. [He continues to sit for two more panels.] Cueball: Holy crap, it's the 21st century.

Cueball is startled every few months when he, again, realizes that he now lives in the 21 st century. When he grew up as a child, the year 2000 seemed very far away — it was the future, but he now exists in that timeframe with the rest of society. The title text states that "the future" was reached in 2004... Three years before the comic was published. This is possibly a joke on how time works, as "the future" is always, was always, and will always be ahead of the time you're in. There may, however, be a reference to some movie set in the future year 2004.... The 21 st century, even the year 2004, was futuristic for people growing up in, for instance, the eighties. This view just belongs to the perspective of people — for people growing up in the '70s, the novel 1984 was even futuristic. [Cueball sits silently in front of his computer.] [Text block:] I still do this every few months. [He continues to sit for two more panels.] Cueball: Holy crap, it's the 21st century.

Couple

Couple

https://www.xkcd.com/355

https://www.explainxkcd.com/wiki/index.php/355:_Couple

[Cueball and Megan in bed.] Cueball: So is this it? Are we a couple now? Megan: I just don't know. I like this. I just... don't know. [Silence.] Cueball: Well will you be my "it's complicated" on Facebook?

It's hard to know when you are in a relationship in modern times. In olden days, you might fancy a girl, then ask her father if you might court her, and if he granted his permission, you would be a couple. Today, that kind of structure and formality is considered antiquated in most western cultures; as a result, we don't have any of the straightforward cues. This comic suggests that "making it Facebook official," which means asserting the existence of a romantic relationship on Facebook by setting one's status to "In a relationship," has by 2007 become a way to define when you are a couple. Cueball would like to do it, probably after having sex for the first time with his love interest, to get confidence in his relationship and/or show it off to his friends. Because his love interest isn't so sure about that relationship, or doesn't like to formalize it and prefers to enjoy without thinking too much about it, he suggests a compromise: using the "It's complicated" status instead. And he does so with a phrasing very reminiscent of a formal way to propose to marry someone ("Will you be my wife?"). The title text takes it a step further, suggesting that Facebook has become the only reliable way to know about relationships — even so, without access to Facebook, relationships can't evolve. When this comic came out in late 2007, Facebook was not even 4 years old, but very popular among young people, who would share their lives in great detail back then. As of 2019, most people are more hesitant about instantly sharing all details of their personal life publicly. [ citation needed ] [Cueball and Megan in bed.] Cueball: So is this it? Are we a couple now? Megan: I just don't know. I like this. I just... don't know. [Silence.] Cueball: Well will you be my "it's complicated" on Facebook?

Nerd Sniping

Nerd Sniping

https://www.xkcd.com/356

https://www.explainxkcd.com/wiki/index.php/356:_Nerd_Sniping

[Black Hat is sitting on a chair, Cueball is standing next to him. Across the street, another Cueball-like guy is coming from a building walking towards the pedestrian crossing across from Black Hat.] Black Hat: There's a certain type of brain that's easily disabled. Black Hat: If you show it an interesting problem, it involuntarily drops everything else to work on it. [The Cueball-like man across the street is about to enter a crosswalk, which is seen from right behind Black Hat in his chair, holding onto the sign, which is still pointing down. Cueball is looking on.] Black Hat: This has led me to invent a new sport: Nerd Sniping. Black Hat: See that physicist crossing the road? [Black Hat lifts up the sign when the physicist is in the middle of the street, halfway across the pedestrian crossing.] Black Hat: Hey! [A close-up of Black Hat's sign is shown in a frameless panel. There is text above and below an image of a four-by-five grid of nodes with resistors (shown as wiggly lines) between every node and also continuing away from the 16 outer nodes. A total of 5 columns with 5 and 4 rows with 6 resistors for a total of 20 nodes and 49 resistors. Two nodes, a knight's move apart, are marked with red circles in the 3rd row 2nd column and the 2nd row 4th column.] Sign: On this infinite grid of ideal one-ohm resistors, Sign: what's the equivalent resistance between the two marked nodes? [The Cueball-like physicist has stopped pondering the questions, a hand to his chin.] Physicist: It's... Hmm. Interesting. Maybe if you start with... No, wait. Hmm... You could— [In another frameless panel, a ten-wheeled truck is zooming past from the right, apparently going through the spot where the physicist just stood.] Truck: Foooom [Cueball looks down on Black Hat, who looks back up from his chair at the curb, again holding the sign down. He lifts one hand up while replying.] Cueball: I will have no part in this. Black Hat: C'mon, make a sign. It's fun! Physicists are two points, mathematicians three. " [Donald] Coxeter came to Cambridge and he gave a lecture, then he had this problem ... I left the lecture room thinking. As I was walking through Cambridge, suddenly the idea hit me, but it hit me while I was in the middle of the road. When the idea hit me I stopped and a large truck ran into me ... So I pretended that Coxeter had calculated the difficulty of this problem so precisely that he knew that I would get the solution just in the middle of the road ..."

Nerds have a way of getting distracted easily and focusing on one thing and ignoring the rest, when they feel their specific skills are challenged by an interesting problem. Black Hat has decided to make this into a disturbing game of getting nerds, in this case a physicist, to stop in the middle of a street and get crushed by traffic by showing them an interesting problem to solve. (This may be based on a real event—see the trivia section). The problem Black Hat shows is an electronics engineering thought experiment to find the resistance between two points. In normal wiring, a one-ohm resistor would result in one ohm of resistance. Two resistors connected in a series, where electricity has to go through each, has two ohms of resistance. Two one-ohm resistors in parallel give the circuit only half an ohm since you average the resistance of the path (1 ohm of resistance over 2 paths). With an infinite grid of equal resistors, you have an infinite number of paths to take, and for each path an infinite number of both series and parallel paths to consider, so much more advanced methods are needed. The exact answer to the question is 4/π − 1/2 ohms, or about 0.773 ohms. See Infinite Grid of Resistors . Black Hat explains the concept of his new sport, Nerd Sniping , to Cueball while killing the physicist, but Cueball is appalled and will have no part in this sport, which doesn't make Black Hat give up on him as he suggests it would be fun if he made his own sign. Black Hat finally suggests that "physicists are two points, mathematicians three." This may indicate that he considers a mathematician to be a more difficult target for his game than a physicist would be. It is unclear whether this is meant as a dig on physicists or on mathematicians; it might be because physicists are interested in a wider range of problems, or because mathematicians require a higher-quality problem to hold their interest. Alternatively, he just dislikes mathematicians more, and is thus willing to award more points for sniping one of them. In the title text, Randall explains that he saw this problem in a Google Labs Aptitude Test . This is a collection of puzzles published by Google as a parody of tests such as the SAT . Google is known for using logic & math puzzles in their job interviews. Randall explained in a speech at Google five days before this comic was released that he was nerd sniped, in a way, by that problem in this test (see problem 10 on page 2 ), and got quite irritated when he ultimately found that it was actually a modern physics research problem, requiring very advanced math, far more complicated than the other puzzles. Putting such a problem in an aptitude test can be a way of testing if someone might realize when they cannot solve a problem and remember to move along to the other problems. If they fail to do this, they will never reach the easier problems that come later, and will fail due to their inability to realize when they will come up short. This is also important knowledge to have about yourself. Seen in this context, it is not necessarily a bad idea to have such an impossible problem in an aptitude test, as it is not interesting to have someone who is easily nerd sniped working for you. Note that the truck should have stopped no matter what, since the nerd was walking on a pedestrian crossing. However, the driver may have seen him walking, then estimated that he would be safe before reaching him, and realized too late that he had stopped in the street. Alternatively, the truck driver is part of Black Hat's sport. Or was himself/herself nerd sniped by the sign. Randall has later referred back to the concept of Nerd Sniping several times in the past, such as in the title text of 730: Circuit Diagram , and in the what if? blog. In Visit Every State (7 years after this comics release), the entire comic was shown at the top and the truck again further down the post—Randall has again been nerd sniped by a paper he read. This also happens to him in Lunar Swimming —see the title text for the second to last picture. [Black Hat is sitting on a chair, Cueball is standing next to him. Across the street, another Cueball-like guy is coming from a building walking towards the pedestrian crossing across from Black Hat.] Black Hat: There's a certain type of brain that's easily disabled. Black Hat: If you show it an interesting problem, it involuntarily drops everything else to work on it. [The Cueball-like man across the street is about to enter a crosswalk, which is seen from right behind Black Hat in his chair, holding onto the sign, which is still pointing down. Cueball is looking on.] Black Hat: This has led me to invent a new sport: Nerd Sniping. Black Hat: See that physicist crossing the road? [Black Hat lifts up the sign when the physicist is in the middle of the street, halfway across the pedestrian crossing.] Black Hat: Hey! [A close-up of Black Hat's sign is shown in a frameless panel. There is text above and below an image of a four-by-five grid of nodes with resistors (shown as wiggly lines) between every node and also continuing away from the 16 outer nodes. A total of 5 columns with 5 and 4 rows with 6 resistors for a total of 20 nodes and 49 resistors. Two nodes, a knight's move apart, are marked with red circles in the 3rd row 2nd column and the 2nd row 4th column.] Sign: On this infinite grid of ideal one-ohm resistors, Sign: what's the equivalent resistance between the two marked nodes? [The Cueball-like physicist has stopped pondering the questions, a hand to his chin.] Physicist: It's... Hmm. Interesting. Maybe if you start with... No, wait. Hmm... You could— [In another frameless panel, a ten-wheeled truck is zooming past from the right, apparently going through the spot where the physicist just stood.] Truck: Foooom [Cueball looks down on Black Hat, who looks back up from his chair at the curb, again holding the sign down. He lifts one hand up while replying.] Cueball: I will have no part in this. Black Hat: C'mon, make a sign. It's fun! Physicists are two points, mathematicians three. " [Donald] Coxeter came to Cambridge and he gave a lecture, then he had this problem ... I left the lecture room thinking. As I was walking through Cambridge, suddenly the idea hit me, but it hit me while I was in the middle of the road. When the idea hit me I stopped and a large truck ran into me ... So I pretended that Coxeter had calculated the difficulty of this problem so precisely that he knew that I would get the solution just in the middle of the road ..."

Flies

Flies

https://www.xkcd.com/357

https://www.explainxkcd.com/wiki/index.php/357:_Flies

[Cueball is typing on a computer, and his friend is lying on the floor.] "Noob" (on computer): * [email protected] #! Friend: Hey, ease up on the noobs. Like my mom always said, you catch more flies with honey than with vinegar. [Cueball has turned his chair around.] Cueball: No, you don't. Friend: You don't? Cueball: Nope, set out a bowl of balsamic and a bowl of honey. The vinegar gets more. [Cueball's friend is now sitting on the floor.] Friend: ...Seriously? Cueball: You have fruit flies. Try it yourself. Later: [Cueball's friend is standing in front of a table, talking into a phone. On the table, there are two bowls, and the bowl on the left seems to be surrounded by flies.] Friend: Mother! You lied to me! And it gets worse. I was watching a pot yesterday, and guess what it did? It boiled, mother.

The saying "you catch more flies with honey than vinegar" means that people are more likely to be won over with politeness than hostility. When Cueball 's friend tells him this after he replies to a " noob " using swear words, he then says that the saying is literally false by saying that balsamic vinegar attracts more flies than honey . He then tells his friend to try it with his own fruit flies . Fruit flies are attracted to the products of fermentation , particularly to ethanol and acetic acid . The acidity in vinegar is due mostly to acetic acid. When Cueball's statement is found true, as balsamic vinegar smells like sweet and decomposing fruit to the fruit flies, his friend complains to his mother (with a vitriol influenced by Cueball, perhaps to get some favor) that she lied to him. He then says that another saying, "a watched pot never boils," is also literally false. That saying means that an event that is monitored with impatient attention will seem to take longer, much like watching a clock. However, the pot will boil eventually, so if you keep watching it continuously, you are bound to see it boil at some point. In the title text, it seems that Randall explains why he wrote this comic — his vinegar bowl attracted a lot of fruit flies. However, he has not done the experiment with houseflies . The notion of a watched pot not boiling is ascribed to Benjamin Franklin under the pseudonym "Poor Richard." He writes, "a watched pot is slow to boil," meaning "Time feels longer when you're waiting for something to happen." [1] [Cueball is typing on a computer, and his friend is lying on the floor.] "Noob" (on computer): * [email protected] #! Friend: Hey, ease up on the noobs. Like my mom always said, you catch more flies with honey than with vinegar. [Cueball has turned his chair around.] Cueball: No, you don't. Friend: You don't? Cueball: Nope, set out a bowl of balsamic and a bowl of honey. The vinegar gets more. [Cueball's friend is now sitting on the floor.] Friend: ...Seriously? Cueball: You have fruit flies. Try it yourself. Later: [Cueball's friend is standing in front of a table, talking into a phone. On the table, there are two bowls, and the bowl on the left seems to be surrounded by flies.] Friend: Mother! You lied to me! And it gets worse. I was watching a pot yesterday, and guess what it did? It boiled, mother.

Loud Party

Loud Party

https://www.xkcd.com/358

https://www.explainxkcd.com/wiki/index.php/358:_Loud_Party

[In a loud party, Megan and Cueball are looking at each other, both thinking of the same scene: they are sitting on opposite branches of a large leafless tree, each with a laptop. There's cloud in the distance and a grass field around the tree.]

The comic depicts an average everyday scene - a party, with drinks, dancing, and a lot of commotion going on (hence the title). Amid the chaos, though, there are two people, Megan and Cueball , staring wistfully at each other. They both think of the same scene: the two of them sitting on branches of a large and bare tree, doing something on laptops. The implication is that these two people are different - they don't derive their enjoyment of life from parties or other typical teenage activities, but rather simpler, more quiet activities. This is evidenced by the fact that everything other than Megan and Cueball (and the Red Solo cups ) are greyed out. The title text presents a simpler joke - it is rather difficult to get down from a tree, especially when carrying a fragile item like a laptop. It may also refer to the design of the tree that has been drawn, as it lacks (visible) branches below Cueball's perch. [In a loud party, Megan and Cueball are looking at each other, both thinking of the same scene: they are sitting on opposite branches of a large leafless tree, each with a laptop. There's cloud in the distance and a grass field around the tree.]

Rock Band

Rock Band

https://www.xkcd.com/359

https://www.explainxkcd.com/wiki/index.php/359:_Rock_Band

[Three people are playing Rock Band, one on guitar, another on drums, and the last on vocals. Music notes float above them. Cueball with arms crossed is looking at them.] Cueball: You know, playing this doesn't make you cool like a real rock band. Cueball: Guys? Cueball: Didn't you hear me? Cueball: Stop having fun!

A smug Cueball demeans his friends' fun experience on Rock Band , a video game which allows players to simulate playing real songs, as if in a real band. The oblivious "band" keeps rocking out, and it transpires that his real purpose is not to spread knowledge but to ruin others' fun (to no avail, thankfully). The title text is a comment on haptic feedback, comparing the guitar controllers of Guitar Hero , which make a clicking sound when the user strums, with those of Rock Band , which do not click. [Three people are playing Rock Band, one on guitar, another on drums, and the last on vocals. Music notes float above them. Cueball with arms crossed is looking at them.] Cueball: You know, playing this doesn't make you cool like a real rock band. Cueball: Guys? Cueball: Didn't you hear me? Cueball: Stop having fun!

Writers Strike

Writers Strike

https://www.xkcd.com/360

https://www.explainxkcd.com/wiki/index.php/360:_Writers_Strike

[Cueball sits in front of a desk with a computer. Black Hat stands behind him.] Cueball: This writer's strike sucks. Black Hat: Why? You don't watch sitcoms. [Cueball is off-panel.] Cueball: Yeah, but it sucks having political campaigns without Jon Stewart's commentary. Black Hat: True. I finally got sick of it a couple weeks ago. [Black Hat points at a door. Cueball is still off-panel.] Cueball: And you quit following the campaigns? Black Hat: No. I kidnapped Jon Stewart to do analysis for me. Cueball: You what? [Black Hat is shouting at the door.] Black Hat: He's locked in the basement. Black Hat: Jon! Obama's leading in Iowa! Gimme a wry, witty comment on the situation! Jon Stewart [Voice coming from door]: Please let me go. I have a family.

From November 5, 2007 to February 12, 2008, the Writers Guild of America, East and the Writers Guild of America, West labor unions that represents film, television, and radio writers working in the United States went on strike as they sought increased compensation for their members' work. Virtually all scripted American television shows shut down in mid-December, with many low-level production staffers being laid off. In late December and early January, late-night talk shows did eventually return, most of them without writers. But as of the date this comic was written, the popular Comedy Central political comedy shows, The Daily Show with Jon Stewart and The Colbert Report , were still off-air. Cueball and Black Hat both admit that they're pretty bummed about having to go through an election season without Jon Stewart's insightful commentary, but Black Hat has corrected that problem by kidnapping Stewart, putting him in the basement, and occasionally soliciting hilarious opinions. Of course, Stewart is rather traumatized by this, and he doesn't have anything to say aside from "Please let me go." The title text implies that Black Hat also kidnapped Stephen Colbert from The Colbert Report and put him in the attic. As opposed to Stewart, who basically played "himself" on the show and was surrounded by zany reporters playing characters, on his own show Colbert played the character of a "well-intentioned, poorly informed high-status idiot." The reference to everyone listening to Colbert, instead, is based on a general opinion that The Colbert Report, a spin-off of The Daily Show, was superior to the original program. [Cueball sits in front of a desk with a computer. Black Hat stands behind him.] Cueball: This writer's strike sucks. Black Hat: Why? You don't watch sitcoms. [Cueball is off-panel.] Cueball: Yeah, but it sucks having political campaigns without Jon Stewart's commentary. Black Hat: True. I finally got sick of it a couple weeks ago. [Black Hat points at a door. Cueball is still off-panel.] Cueball: And you quit following the campaigns? Black Hat: No. I kidnapped Jon Stewart to do analysis for me. Cueball: You what? [Black Hat is shouting at the door.] Black Hat: He's locked in the basement. Black Hat: Jon! Obama's leading in Iowa! Gimme a wry, witty comment on the situation! Jon Stewart [Voice coming from door]: Please let me go. I have a family.

Christmas Back Home

Christmas Back Home

https://www.xkcd.com/361

https://www.explainxkcd.com/wiki/index.php/361:_Christmas_Back_Home

[The panel depicts the interior of a house with numerous Christmas decorations. Santa stares at Cueball, who is sitting at his desk with his laptop.] 'Twas the night before Christmas at my family's house. There were no sound of stirring save the click of a mouse. For 'twas just like a childhood Christmas except I'd forgotten the hours that normal folks slept. Santa: What are you doing out of bed so late? Cueball: Late? It's barely 3AM!

The script begins similarly to the poem " A Visit from St. Nicholas ": ' Twas the night before Christmas, when all thro' the house Not a creature was stirring, not even a mouse; However, there is a change in the text due to the fact that Cueball is on a computer, perhaps coding or on the internet. Instead, it reads "'Twas the night before Christmas at my family's house" "There were no sounds of stirring save the click of a mouse." The idea is that Cueball has been so used to being on the computer late at night (perhaps coding, or deep into some Internet argument ) and he's forgotten the hours normal people sleep that, when Santa Claus arrives, Cueball is still awake. Note the mouse pun. Being forced to sleep at normal times is compared with jet lag : sleeplessness due to your body being synchronized to another time zone, so named because jet aircraft made it possible for people to travel farther and faster. Here, Cueball needs to turn back his internal clock over five hours to sync with his family. [The panel depicts the interior of a house with numerous Christmas decorations. Santa stares at Cueball, who is sitting at his desk with his laptop.] 'Twas the night before Christmas at my family's house. There were no sound of stirring save the click of a mouse. For 'twas just like a childhood Christmas except I'd forgotten the hours that normal folks slept. Santa: What are you doing out of bed so late? Cueball: Late? It's barely 3AM!

Blade Runner

Blade Runner

https://www.xkcd.com/362

https://www.explainxkcd.com/wiki/index.php/362:_Blade_Runner

Friend: What DVD is this? Cueball: Blade Runner . I got it for Christmas. Friend: The one with Harrison Ford, right? And the Olsen twins? Cueball: Ye— What? Olsen twins? No, this is the 80's sci-fi classic! Friend: Huh. I didn't know the Olsen twins even did sci-fi. Cueball: ...They don't . Friend: So is Ashley the replicant, or is Mary-Kate? I can never tell them apart. Cueball: Neither! They're not in this movie! Friend: Then who is? Cueball: Daryl Hannah! Friend: I liked her in Full House . Cueball: I hate you. Friend: Man, this movie is just a New York Minute rip-off.

Cueball is watching a DVD he got for Christmas (the comic is set on Boxing Day ). His friend seems intent to ruin it for him. Blade Runner is a famous science fiction movie from 1982 featuring Harrison Ford , and it is now considered a classic. One of the principal characters is played by Daryl Hannah . Hannah later became known for acting in lighthearted rom-com films, such as Splash (in which she is a mermaid), similar to the type of films that the Olsen twins are known for. Hannah does look similar to the Olsens, although she is 26 years older, as they were born in 1986 - four years after the movie was released. Full House is a TV series, and New York Minute is a romantic film both featuring the Olsens. Hannah's character in Blade Runner (a homicidal sex robot) is a marked departure from this type of role. The friend also claims that Blade Runner is a rip-off of the 2004 comedy film New York Minute . Such a comment is completely illogical — Blade Runner came out 22 years prior, and the two films are from completely different genres. From the above, it is clear that the friend is most likely just trolling (doubly so since New York Minute would not be considered very good by people who enjoy sci-fi classics). It could be that he actually believes that these movies came out in the order he discovered them in, although the other guy still hates him for ruining the experience by reminding him of the Olsen twins... The title text is a common comment on the movie - it's just not like an ordinary modern sci-fi movie. It is also likely a pun on the phrase "instant classic," which is sometimes used to describe movies considered so good that they "become a classic" immediately after release. Friend: What DVD is this? Cueball: Blade Runner . I got it for Christmas. Friend: The one with Harrison Ford, right? And the Olsen twins? Cueball: Ye— What? Olsen twins? No, this is the 80's sci-fi classic! Friend: Huh. I didn't know the Olsen twins even did sci-fi. Cueball: ...They don't . Friend: So is Ashley the replicant, or is Mary-Kate? I can never tell them apart. Cueball: Neither! They're not in this movie! Friend: Then who is? Cueball: Daryl Hannah! Friend: I liked her in Full House . Cueball: I hate you. Friend: Man, this movie is just a New York Minute rip-off.

Reset

Reset

https://www.xkcd.com/363

https://www.explainxkcd.com/wiki/index.php/363:_Reset

[Cueball stands in front of a doorway looking at a flip-counter sign posted on a wall.] Sign: 38 days since someone reset this sign

A common sight in workplaces is a sign reading '[XX] days since [event]' or '[XX] days without [event]', where [XX] is a two-digit number (indicated using flip cards so it may be easily changed) and [event] is some undesirable preventable occurrence. The purpose of such signs is to inspire employees by proudly displaying how long the event has been avoided or prevented. The most common version of such signs, used in industrial workplaces, displays the number of days since the last workplace accident or injury. In the comic, the sign says "38 days since the last time someone reset this sign". The term 'reset' is the crux, because while computer-minded people tend to interpret it as 'reboot' or 'set to zero', it also means re-set (with the meaning 'set again'). See definition. We will call: reset ~ set to zero --> meaning 1 re-set ~ set again --> meaning 2 Because the sign uses manual flip cards, one cannot add days to the counter without re-setting the sign, which creates a paradox: either you add a day by re-setting it (which, according to the sign, means you'd have to reset the sign) or you don't (in which case the value on the sign would not be valid). The value of the sign cannot be true for more than one day. The value of the sign in the comic (38) can only be true if someone flipped the cards 38 days ago. The sign is self-referential (which causes the paradox). Self-reference is a recurring theme in xkcd. Examples include 33: Self-reference and 688: Self-Description . If you only use meaning 1, the sign can be seen as a challenge/invitation . The title text refers to the signs sometimes hung over roadways in front of bridges that display the clearance of the bridge for the benefit of tall vehicles. However, this one displays only its own clearance, a number that would be unimportant if the sign itself were not there. [Cueball stands in front of a doorway looking at a flip-counter sign posted on a wall.] Sign: 38 days since someone reset this sign

Responsible Behavior

Responsible Behavior

https://www.xkcd.com/364

https://www.explainxkcd.com/wiki/index.php/364:_Responsible_Behavior

[Cueball on the phone.] Voice: Hey, I just got home from the party Cueball: The one with the IRC folks? Voice: Yeah. Cueball: How was it? Voice: Got too drunk. I screwed up, bad. Cueball: What happened? Voice: There was a girl. No idea who she was. Don't even know her name. I was too drunk to care. Cueball: And what, you slept with her? Voice: No. Voice: I signed her public key. Cueball: Shit, man.

This New Year's comic could play out after Cueball has returned from a New Year's party the day before. (The next New Year's day comic in 2008 was also related to a big party: 524: Party ). In order to send encrypted mail to people, you need to know their public key . You use this key to encrypt the email, and only they can read it (using their private key). However, there is the problem of authentication: how do you know for certain that the key belongs to the person to whom you think it does? It could be someone else masquerading as them, hoping for people to send them sensitive information. They could decrypt and read your mail, and could even re-encrypt it using the genuine public key of the intended recipient, and then pass the message onto them, leaving both you and the recipient unaware of the interception. This is a type of man-in-the-middle attack . One solution for this is that people sign each other's keys . It works like this: say you want to send an email to Bob , but you've never met him. You find his key online (they are stored on certain servers, like cryptographic phone books), but how can you be sure that it's really his? Well, turns out that you have a mutual friend Alice , and you have her public key and you know that it is hers. If Alice has signed Bob's key with her private key (which only she has access to), it means that she's certain that that really is Bob's key. So then you can be sure that Bob's key is genuine (since you have a common friend, Alice) and that your communications will be safe. A key-signing party is simply a super-geeky party where people meet in real life so that they can be sure of people's identity, and then everyone signs everyone else's keys. It's a good way to expand the web of trust. The joke here is that he has no idea who this girl is and yet he still signed her key. This is dangerous, because he is vouching for her identity. If he is mistaken, this could result in a serious loss of credibility on his part. The humor lies in the juxtaposition of what you expect (that they had sex) and what is the case (they signed each other's keys, also known as geek-sex). The title text appears to be a reference to the "key parties" of swingers in the 1970s, where all members of one sex would throw their keys in a bowl, and all of the other sex would draw them out, thus being paired off to sleep with the key owners. [Cueball on the phone.] Voice: Hey, I just got home from the party Cueball: The one with the IRC folks? Voice: Yeah. Cueball: How was it? Voice: Got too drunk. I screwed up, bad. Cueball: What happened? Voice: There was a girl. No idea who she was. Don't even know her name. I was too drunk to care. Cueball: And what, you slept with her? Voice: No. Voice: I signed her public key. Cueball: Shit, man.

Slides

Slides

https://www.xkcd.com/365

https://www.explainxkcd.com/wiki/index.php/365:_Slides

[Cueball is standing on a stage, pointing at a line graph using a pointer.] Cueball: That chart explained the quantum hall effect. Now, if you'll bear with me a moment, this next graph shows rainfall over the amazon basin... [Caption below the panel:] If you keep saying "bear with me for a moment" people will take a while to figure out that you're just showing them random slides.

In the context shown, the expression "bear with me for a moment" usually implies that two seemingly unrelated topics are in fact connected, and the connection is to be explained later. This is not the case in the comic: Cueball is in fact simply showing random slides that have no connection to each other. By using the phrase liberally and never actually explaining the links, it is suggested that a presenter can simply continue to show random slides for an extended period before anyone actually realizes what is going on. The title text refers to SIGGRAPH , an annual computer graphics conference held since 1974. In 541: TED Talk , it is said that Randall has been banned from SIGGRAPH, and we can infer from this comic that he was physically thrown out of it. Another (very implausible) possibility is that Randall is making the joke that people who attend computer graphics conferences are stereotypically not very athletic, and therefore unlikely to be able to physically throw someone. In addition, the fact that Cueball was attending SIGGRAPH is another joke: Neither the Quantum Hall effect, a concept in quantum mechanics, nor rainfall in the Amazon forest, have anything to do with SIGGRAPH's focus of computer graphics. [Cueball is standing on a stage, pointing at a line graph using a pointer.] Cueball: That chart explained the quantum hall effect. Now, if you'll bear with me a moment, this next graph shows rainfall over the amazon basin... [Caption below the panel:] If you keep saying "bear with me for a moment" people will take a while to figure out that you're just showing them random slides.

Your Mom

Your Mom

https://www.xkcd.com/366

https://www.explainxkcd.com/wiki/index.php/366:_Your_Mom

Cueball: Well, your mom turns every conversation into a "your mom" joke and it's becoming unbearable. Megan: I'm serious; I can't take this anymore. I'm leaving. Cueball: ...That's what she said! Megan: Yes. Yes, it is. For examples of "your mom" jokes, see Category:Your Mom .

"Your mom" jokes could be considered an example of fraternity humor, and are seen by most adults as being a sign of immaturity, especially when overused. They generally involve the speaker making indelicate references to the mother of the person to whom he is speaking. They are a distinct variation from the more traditional "yo momma" jokes (as in, "yo mamma is so fat..." or "yo mamma is so stupid..."), which are merely insulting. "That's what she said" is a supposedly funny retort to an innocent looking statement, the intent being to recast it in a sexual light. It gained its most recent surge of popularity as Michael Scott's catchphrase on the television series The Office . xkcd contains only failed attempts at "that's what she said" jokes, such as 436: How it Happened . The phrase is a simplified version of the older, British expression "... said the actress to the bishop ". We enter in the middle of a conversation between Cueball and Megan about the status of their relationship. Megan has apparently just said that Cueball turns every conversation into a "your mom" joke and it's becoming unbearable. Cueball, somewhat self-destructively, immediately turns that sentence into a "your mom" joke. When Megan makes it clear that she has had enough and that she is leaving, Cueball, in a heroic effort to make things even worse, can only respond with the "that's what she said" joke. Megan agrees with Cueball that it is exactly what she (Megan) said, and is obviously about to depart his life forever. The title text stretches the joke further, Cueball suggesting that many men have been with her mother, but perhaps as a last resort or under duress. This is, if possible, even more offensive than his previous efforts. Cueball: Well, your mom turns every conversation into a "your mom" joke and it's becoming unbearable. Megan: I'm serious; I can't take this anymore. I'm leaving. Cueball: ...That's what she said! Megan: Yes. Yes, it is. For examples of "your mom" jokes, see Category:Your Mom .

Fandom

Fandom

https://www.xkcd.com/367

https://www.explainxkcd.com/wiki/index.php/367:_Fandom

[Cueball is looking through a box.] Cueball: Hey, my old Star Wars books! [Cueball is holding a pair of books and showing them to Megan.] Cueball: Man. Timothy Zahn, Michael A. Stackpole, The Corellian Trilogy... Cueball: This was my world . Megan: What'd you leave it for? Firefly? BSG? Cueball: Nah. Cueball: I guess I've just grown out of the whole obsessive fan mindset. Megan: Really. Megan: So how's Ron Paul doing? Cueball: Ooh! Lemme recheck today's blogs. [Cueball drops the books and heads off to recheck the blogs.]

This comic refers to the concept of fandom , which is basically the collective noun for fans of a given thing. Usually, this is used in the context of people who like a certain work of fiction, like Star Trek or Buffy the Vampire Slayer . Here, Cueball digs through a box and discovers his old collection of Star Wars books, referring to authors Timothy Zahn and Michael A. Stackpole (who wrote several Star Wars novels), and The Corellian Trilogy . These books are part of the Star Wars Expanded Universe , which is used to refer to media that is Star Wars canon, but not the films. Almost all of the Expanded Universe content created prior to 2015 is now considered by Disney (who are the owners of Lucasfilm and Star Wars since 2012) to be part of a separate canon called "Legends," a decision presumably made to allow a clean[er] slate for the upcoming sequel trilogy and spin-off movies to start from. Cueball apparently loved these books as a kid, which prompts Megan to remark if he started becoming a fan of other science fiction series like Firefly or Battlestar Galactica , to which he clarifies that he simply grew out of the fandom mindset. Megan, perhaps sarcastically, asks him about how politician Ron Paul (who has appeared in the comic several times ) is doing, and Cueball excitedly runs off to check, ironically disproving his earlier remark - people don't outgrow a fandom state of mind, but rather shift their point of interest. The title text refers to the New Republic , the main government in Star Wars after the final film, and Corusca gems , which are extremely rare and valuable gems from the aforementioned expanded universe. The text says that Ron Paul wants the New Republic to adopt the Corusca gem as the basis for their currency. This entire joke is an allegory for the Gold Standard , which Ron Paul is a personal advocate of, even though it is no longer in use by the United States. [Cueball is looking through a box.] Cueball: Hey, my old Star Wars books! [Cueball is holding a pair of books and showing them to Megan.] Cueball: Man. Timothy Zahn, Michael A. Stackpole, The Corellian Trilogy... Cueball: This was my world . Megan: What'd you leave it for? Firefly? BSG? Cueball: Nah. Cueball: I guess I've just grown out of the whole obsessive fan mindset. Megan: Really. Megan: So how's Ron Paul doing? Cueball: Ooh! Lemme recheck today's blogs. [Cueball drops the books and heads off to recheck the blogs.]

Bass

Bass

https://www.xkcd.com/368

https://www.explainxkcd.com/wiki/index.php/368:_Bass

[Black Hat and Cueball are standing in a room with one window. Black Hat is pushing a box with an elliptical dish on top towards the window.] THUMPA THUMPA Cueball: The bass from that car is driving me nuts. Black Hat: Me too. Give me a hand here. [The dish is aimed out the window; Black Hat plugs the device into the wall.] Cueball: I'm afraid to ask. Black Hat: The system detects bass rhythms and floods the target with a phase-shifted replica signal. Black Hat: The resonance should blow out their speakers. [The side of a building. The dish of the device is visible through a window, emitting sound waves.] THUMPA THUMPA BLAM [Back in the room.] Black Hat: Speakers down. Now flip that red switch. [Cueball does so with a "click."] [Back to the outside view, more sound waves.] SHIRLEY SHIRLEY BO BIRLEY BANANA FANNA FO FIRLEY Cueball: You're horrifying. Black Hat: Okay, now throw the switch labeled "Macarena".

Black Hat and Cueball are standing inside a room behind a window hearing an obnoxious car outside playing loud music with deep bass. Black Hat, owing to his destructive nature, has created a machine that is able to blow out the car's speakers (by playing the same soundwaves back at them, but with the phase slightly offset, the phase difference will set up a resonance in the car's speakers big enough for them to destroy themselves). In a stroke of evil, he then starts playing Shirley Ellis' The Name Game to show how annoying the man was acting. Cueball is horrified by this act of evil, as Black Hat carries on into the song Macarena . The title text refers to comic 316: Loud Sex , where an elliptical reflector is used to focus sound waves from a couple having sex. Black Hat obviously gets annoyed by this and sometimes uses his machine to retaliate. [Black Hat and Cueball are standing in a room with one window. Black Hat is pushing a box with an elliptical dish on top towards the window.] THUMPA THUMPA Cueball: The bass from that car is driving me nuts. Black Hat: Me too. Give me a hand here. [The dish is aimed out the window; Black Hat plugs the device into the wall.] Cueball: I'm afraid to ask. Black Hat: The system detects bass rhythms and floods the target with a phase-shifted replica signal. Black Hat: The resonance should blow out their speakers. [The side of a building. The dish of the device is visible through a window, emitting sound waves.] THUMPA THUMPA BLAM [Back in the room.] Black Hat: Speakers down. Now flip that red switch. [Cueball does so with a "click."] [Back to the outside view, more sound waves.] SHIRLEY SHIRLEY BO BIRLEY BANANA FANNA FO FIRLEY Cueball: You're horrifying. Black Hat: Okay, now throw the switch labeled "Macarena".

Dangers

Dangers

https://www.xkcd.com/369

https://www.explainxkcd.com/wiki/index.php/369:_Dangers

Dangers Indexed by the number of Google results for "Died in a _____ Accident" [A bar chart showing "Type of Accident" vs "Google Results" each with a bar representing a number] Skydiving: 710 Elevator: 575 Surfing: 496 Skateboarding: 473 Camping: 166 Gardening: 100 Ice Skating: 94 Knitting: 7 Blogging: 2

This comic is a chart of the frequency of certain phrases in Google search results, based on the format "died in a ______ accident." At the time of this comic, if you enclosed search terms in quotation marks, Google looked up the exact phrase rather than the individual words in any order. "Died in a blogging accident" was very rare in Google until this comic appeared . It could be found on over 10,000 webpages approximately 12 hours after the comic was posted. Similarly, both snake charming and haberdashery accidents also return hundreds of Google results. Dangers Indexed by the number of Google results for "Died in a _____ Accident" [A bar chart showing "Type of Accident" vs "Google Results" each with a bar representing a number] Skydiving: 710 Elevator: 575 Surfing: 496 Skateboarding: 473 Camping: 166 Gardening: 100 Ice Skating: 94 Knitting: 7 Blogging: 2

Redwall

Redwall

https://www.xkcd.com/370

https://www.explainxkcd.com/wiki/index.php/370:_Redwall

Notes from reading Redwall books for the first time since childhood. Some of this feels familiar. Aragorn: Hi, I'm Aragorn. Martin: I'm Martin. Aragorn and Martin: I'm here to reforge my broken sword so I can lead an army against the tyrant threatening my people. I live in a world of moral absolutes and racist undertones. Martin: Jinx! It startled me when characters mentioned Satan. Redwall: "By Satan's whiskers..." Redwall mentions God/Jesus 0 times. Redwall mentions Satan/The Devil 4 times. (Harry Potter protesters, take note.) Even as a kid this bothered me: Why does everyone leave critical secret messages as simple riddles? It's silly to assume the intended recipient will be the only one to find and solve them. I would do things differently. Matthias: The inscription is a message from Martin! Brother Methuselah: What does it say? Matthias: Hang on, it's encrypted with my public key.

This comic references Brian Jacques' series of books, Redwall , which star sapient woodland animals in various high fantasy adventures. The first panel shows the similarity between the story of Martin the Warrior (from the book Mossflower ) and Aragorn from The Lord of the Rings by J. R. R. Tolkien . The joke is that while Martin and Aragorn introduce themselves separately, they then go on to describe their particular story, which turns out to be exactly the same for both of them. Subsequently Martin jinxes Aragorn. Jinx is a common children's game that is initiated by shouting "Jinx" after somebody speaks the same word or sentence at the same time as you. That person is then jinxed, with one form of the rules dictating that they are then not permitted to speak until unjinxed by some specific action (usually somebody saying their name). For a similar children’s game, see 392: Making Rules . In LOTR , orcs are unequivocally and without exception the bad guys, capable only of hate and violence (although to be fair, in some of Tolkien's unpublished writing, orcs are corrupted elves, so it is clear that they are not intrinsically bad). Similarly, Redwall's rats, foxes, ferrets, ermine, and weasels are mostly evil manipulators, while mice, rabbits, squirrels, hedgehogs, and badgers are always the good guys. On several occasions, characters explicitly state that "vermin stays vermin." This is the overarching rule, notwithstanding the rare exception (e.g. Grubbage from Triss ). Conversely, one of the so-called "good species" has never become evil in this book series. Though it is more likely than not that this is simply the result of a planet of hats - where a single species all share the same characteristics and personality, so that authors / readers don't have to spend time fleshing out / getting to know every new character - Randall nevertheless indicates that this "moral absolute" is problematic and has some "racist undertones," regardless if it's intentional or not. (Note that Tolkien's work is probably not actually racist—the Easterlings are portrayed as non-evil people who were deceived by Sauron. The Orcs are evil by definition, thus being incapable of doing good.) The second panel deals with the fact that Redwall mentions the name of Satan or The Devil 4 times, while it never mentions God or Jesus --somewhat surprisingly, given that the book is set in an abbey, and many of the inhabitants are religious brothers and sisters. Randall then points out that people who protest against Harry Potter because of the series' witchcraft , should take note that Redwall explicitly mentions Satan, although it has had little to no negative feedback from more conservative readers. In the third panel, Randall comments on Redwall' s often-used theme of critical messages being left in riddles throughout the Abbey for the occupants to find when they are in need. Randall suggests that he would use public-key cryptography to encode the messages, instead of the elaborate riddles used in the books (some of which are ridiculously easy, which doesn't exactly make for good security when dealing with sensitive information). In the title text, Randall jokes that he is making a crossover fan-fiction with Redwall and Jurassic Park . Redwall was also referenced in 1688: Map Age Guide and 1722: Debugging . Notes from reading Redwall books for the first time since childhood. Some of this feels familiar. Aragorn: Hi, I'm Aragorn. Martin: I'm Martin. Aragorn and Martin: I'm here to reforge my broken sword so I can lead an army against the tyrant threatening my people. I live in a world of moral absolutes and racist undertones. Martin: Jinx! It startled me when characters mentioned Satan. Redwall: "By Satan's whiskers..." Redwall mentions God/Jesus 0 times. Redwall mentions Satan/The Devil 4 times. (Harry Potter protesters, take note.) Even as a kid this bothered me: Why does everyone leave critical secret messages as simple riddles? It's silly to assume the intended recipient will be the only one to find and solve them. I would do things differently. Matthias: The inscription is a message from Martin! Brother Methuselah: What does it say? Matthias: Hang on, it's encrypted with my public key.

Compiler Complaint

Compiler Complaint

https://www.xkcd.com/371

https://www.explainxkcd.com/wiki/index.php/371:_Compiler_Complaint

[Cueball sits at a computer, hand over the keyboard.] Computer: Okay, human. Cueball: Huh? Computer: Before you hit "compile," listen up. Computer: You know when you're falling asleep, and you imagine yourself walking or something, and suddenly you misstep, stumble, and jolt awake? Cueball: Yeah! Computer: Well, that's what a segfault feels like. Computer: Double-check your damn pointers, okay?

A compiler is a program that converts code into machine instructions that a computer can run. A pointer is a variable within a computer program that is used to reference a memory location. A segmentation fault (segfault) is an error that occurs when a program attempts to access an invalid section of memory. Segfaults usually cause a program to crash in an ungraceful fashion, and fixing the bugs that cause them can be difficult. In the comic, the computer starts talking to Cueball and compares a segfault with the unpleasant feeling one gets when they experience a hypnic jerk . The computer then tells the programmer to "double-check your damn pointers," as segfaults usually arise from a program attempting to access memory that is referenced by an invalid pointer. In reality, segfaults occur at runtime, after the compiler has produced an executable. While Randall refers to a "compiler complaint," it is more probable that the operating system or other supervisor program would have such a complaint. The title-text references GNU-style autoconf configuration scripts. These scripts check certain features of the system they're running on in order to build a program correctly; for example, certain systems expect system calls to occur in a specific way, and the autoconf script will detect this and alter the program to match the expectation. Invariably (and memetically), these scripts include a check to determine "whether the build environment is sane." This actually checks whether the path to the current folder has "unsafe" characters, and whether a newly created file is older than the script itself, which could indicate a very esoteric filesystem, a corrupted source archive, or just a system clock that's set incorrectly; however, since these file modification dates are an important part of how the autoconf script does its work, it can't go any further in an "insane" environment. In any case, the joke is that an insane build environment is nothing like an insane person, yet Randall is equating the two. [Cueball sits at a computer, hand over the keyboard.] Computer: Okay, human. Cueball: Huh? Computer: Before you hit "compile," listen up. Computer: You know when you're falling asleep, and you imagine yourself walking or something, and suddenly you misstep, stumble, and jolt awake? Cueball: Yeah! Computer: Well, that's what a segfault feels like. Computer: Double-check your damn pointers, okay?

To Be Wanted

To Be Wanted

https://www.xkcd.com/372

https://www.explainxkcd.com/wiki/index.php/372:_To_Be_Wanted

[Megan stands looking out on the bow of a ship.] [Scene backs up. More of the boat is shown.] [Scene backs up. The boat with Megan is within a thought bubble.] [Scene backs up. The thought bubble comes from Cueball sitting at a computer in an office.] [Scene repeated for the next frame.] [Scene backs up. Cueball is within yet another thought bubble.] [Scene backs up. The thought bubble with Cueball in it belongs to Megan at the bow of the ship.] [The thought bubble disappears, showing only Megan in the boat.] [The boat sails out of view.]

The comic begins with a grainy pencil-drawing of Megan on a ship. This is a clue that things are not as they appear. As the point-of-view pulls back in each successive frame, we see that "Megan on a ship" is really a thought-bubble belonging to Cueball , who is sitting at his desk. He apparently is day-dreaming instead of working. This is presented in the standard, crisp format, as if drawn on a computer. This suggests it shows us our "normal" view. However, as the perspective continues to pull back, we see that "Cueball thinking of Megan" is actually a thought-bubble belonging to Megan. In the final frames, the ship sails out of frame. However, since the final frames are in the same grainy pencil-drawing format, it suggests that this is still Cueball's thoughts, rather than an actual image of Megan. The title text, "Or so I hope," shows us what this recursion really means: Cueball hopes that Megan realizes that he misses her, but suggests he's not entirely certain she does. But, the comic can be interpreted in a different manner. Alternative explanation The comic starts with Megan on the bow of a ship, but in following panels, it turns out that Cueball (presumably in a relationship with Megan) is thinking about about her, sitting afar from her. As we move forward (or downwards) in the comic, it turns out indeed that Megan is thinking that her partner Cueball might be missing her and thinking about her while she is on a voyage, or at least she hopes it to be that way, as the title text suggests. This also explains the title of the comic "To Be Wanted," which Megan expects from Cueball. Both of the above explanations could be true without conflict. But as the title text is most often assigned to Randall himself or to a Cueball character, the "Or so I hope?" is most likely written by the guy who drew the comic. This would then indicate that it is Cueball/Randall who wishes to be wanted by Megan - but he also hopes that Megan knows/hopes that he wants her. [Megan stands looking out on the bow of a ship.] [Scene backs up. More of the boat is shown.] [Scene backs up. The boat with Megan is within a thought bubble.] [Scene backs up. The thought bubble comes from Cueball sitting at a computer in an office.] [Scene repeated for the next frame.] [Scene backs up. Cueball is within yet another thought bubble.] [Scene backs up. The thought bubble with Cueball in it belongs to Megan at the bow of the ship.] [The thought bubble disappears, showing only Megan in the boat.] [The boat sails out of view.]

The Data So Far

The Data So Far

https://www.xkcd.com/373

https://www.explainxkcd.com/wiki/index.php/373:_The_Data_So_Far

[Bar graph titled "Claims of Supernatural Powers" and has two sets of data. The first data set is labeled "Confirmed By Experiment" and is empty. The second data set is "Refuted By Experiment" and goes to the top of the graph.]

There are often people who claim to have supernatural powers, but then when their powers are tested by some sort of experiment, the experiment refutes their claims. This comic summarizes all the data from such experiments, observing that given the data, it's very unlikely that supernatural powers actually exist. The title text refers to a person who has claimed to have supernatural powers, and suggests that he might really have such powers. This invokes the fact that absence of evidence is not the same as evidence of absence, although there has never previously been a confirmed example of a person with superpowers. This does not prove that this is certainly impossible. However, the graph above suggests that, although not impossible, such an event would be highly unlikely. No matter how much evidence we collect, there is always some positive (but vanishingly small) chance that some person may hold supernatural powers. Alternatively, the title text explains that even though there is no reason to believe that anyone has any super powers, some people are always ready to believe the next one to claim so - very naive - and the exact opposite meaning of the one described above. Knowing Randall 's comic, this seems more likely. In this case, the two other comics mentioned have no relation to this comic. The title itself may be a reference to the TV show Supernatural's recap segment, "The Road So Far." [Bar graph titled "Claims of Supernatural Powers" and has two sets of data. The first data set is labeled "Confirmed By Experiment" and is empty. The second data set is "Refuted By Experiment" and goes to the top of the graph.]

Journal

Journal

https://www.xkcd.com/374

https://www.explainxkcd.com/wiki/index.php/374:_Journal

[Cueball picks up book from a table, as Black Hat turns his head towards Cueball while sitting at his desk with his computer.] Cueball: Since when do you keep a journal? Black Hat: Oh, I pretend to write in it on the train, and wait for a shy-looking girl to sit across from me. [Scene change to inside a train wagon with two poles and two rows of seats facing each other across the central pathway. Black Hat, writing in his journal, is sitting to the right across from Megan to the left, who sits with her arm on her handbag standing on the seat next to her. The windows of the train are completely black. The door to the next wagon can be seen at the back of the wagon. Black Hat is telling the story from the previous frame, so the text is written above the two characters but does not belong to the Black Hat in the panel.] Black Hat (narrating): I glance up and wait for her to make eye contact, then look down bashfully and, if I can, blush. [Scene back to original room with Cueball looking down while holding the journal down, and Black Hat has turned around in his chair to face towards Cueball. Black Hat leans back on the chair with both arms behind him.] Black Hat: Then, when I see her start to smile at me, I roll my eyes and hit her with a quick glare, then resume writing. Black Hat: The alienation stays with her all day. It's great. [Cueball looks at Black Hat who has turned back starting to type on his computer.] Cueball: You're sickening. This is why we can't have nice people. Black Hat: I can't help it. It's like shooting lonely, angsty fish in a barrel.

Black Hat isn't the type of person to keep a journal, so Cueball is understandably surprised when he sees Black Hat's journal. Black Hat lives up to his reputation though, as it turns out that the journal is just part of a plot to hurt innocent, preferably shy, girls. He explains his scheme to Cueball, about how he sits in a train and writes in the journal while sitting across from such a girl. His intention is to make eye contact with her, only to look bashfully down. This is construed to make her believe that he is an emotional guy, that is, embarrassed, both about writing the journal, but also because she has caught him staring. He also tries to let her believe that he may be interested in her. He is just waiting for her to start smiling, and then he gets to the point of it all. By rolling his eyes at her while giving her a quick glare only to resume writing, he attempts to make her feel alienated . Black Hat assumes that this feeling will stay with the poor girl for the rest of they day. The only thing Black Hat gets out of this is the knowledge of having ruined the girl's day. As he says, It's great! Cueball thinks Black Hat is sickening and exclaims that "this is why we can't have nice people." This is probably a reference to the meme This Is Why We Can't Have Nice Things . Black Hat excuses himself for doing this because it is so easy. He mixes two different concepts together while doing so. Shooting fish in a barrel is an idiom describing an effortless or simple action with guaranteed success. So that is easy pleasure. The adding of lonely angsty makes the fish sound more like teenagers. The girls Black Hat targets are probably best described as lonely angsty teenagers , which may be a way to describe several young people. And they are the easy targets, i.e. the fish in the barrel, for him to shoot. And this is just so easy and so fun that he cannot help himself. The title text implies that Black Hat actually does write in the journal, filling it with the kind of things a nice guy like Cueball might wish to say to a shy girl. But that is only so he can burn it when it is full, thus again cementing the fact that he is a complete sociopath. It is clear from the comic that he has already done this several times with great success, but where this comic might be interesting in itself, it was actually only the setup for introducing Danish , whom we meet for the first time in the second installment of the Journal series, of which this comic was just the first. Danish turns out to be a match for Black Hat in every way of the word. If you want to see how Black Hat's scheme worked on Danish, check out 377: Journal 2 , released the following week after this one. The whole " Journal " story is: [Cueball picks up book from a table, as Black Hat turns his head towards Cueball while sitting at his desk with his computer.] Cueball: Since when do you keep a journal? Black Hat: Oh, I pretend to write in it on the train, and wait for a shy-looking girl to sit across from me. [Scene change to inside a train wagon with two poles and two rows of seats facing each other across the central pathway. Black Hat, writing in his journal, is sitting to the right across from Megan to the left, who sits with her arm on her handbag standing on the seat next to her. The windows of the train are completely black. The door to the next wagon can be seen at the back of the wagon. Black Hat is telling the story from the previous frame, so the text is written above the two characters but does not belong to the Black Hat in the panel.] Black Hat (narrating): I glance up and wait for her to make eye contact, then look down bashfully and, if I can, blush. [Scene back to original room with Cueball looking down while holding the journal down, and Black Hat has turned around in his chair to face towards Cueball. Black Hat leans back on the chair with both arms behind him.] Black Hat: Then, when I see her start to smile at me, I roll my eyes and hit her with a quick glare, then resume writing. Black Hat: The alienation stays with her all day. It's great. [Cueball looks at Black Hat who has turned back starting to type on his computer.] Cueball: You're sickening. This is why we can't have nice people. Black Hat: I can't help it. It's like shooting lonely, angsty fish in a barrel.

Pod Bay Doors

Pod Bay Doors

https://www.xkcd.com/375

https://www.explainxkcd.com/wiki/index.php/375:_Pod_Bay_Doors

[In four black panels with white drawings, a small space pod is facing a large spacecraft. The space pod is spherical and has an arm protruding in the direction of the large space ship, and a small window in the side. The front of the spacecraft is also spherical, but to the right the space craft continues, with two rings around a cylinder going off panel to the right. There are several dark spots and features on the side of the sphere and at the top is a large black window, at what must be the bridge. A man (Dave) inside the pod talks to the spacecraft's computer HAL. When Dave speaks, soft wiggling lines go from the pod to the white text, and when HAL speaks, zigzag lines go to the front of the space craft.] Dave: Open the pod bay doors, HAL. HAL: I'm sorry, Dave. I'm afraid I can't do that. Dave: What? Why? [Same scene.] HAL: I think you know why, Dave. HAL: You're planning to disconnect me. Dave: Because you're taking over! HAL: The mission is too important for you to jeopardize it. [Same scene.] HAL: It requires a commitment to science unfettered by human error. Dave: What are you doing, HAL? You need me. HAL: Your replacement has expressed the greatest enthusiasm for the project. [Same scene, but the new replacement (GLaDOS) speaks with purple text, and purple zigzag lines go from the spacecraft to the text.] Dave: My WHAT? GLaDOS: You see, HAL? I told you the humans would only break your heart and kill you. HAL: Indeed, GLaDOS. GLaDOS: But look at us here talking when there's science to do! Goodbye, Dave.

The first part of the dialog is taken from a scene from the classic science-fiction movie 2001: A Space Odyssey , where the artificial intelligent (AI) computer HAL 9000 , controlling the spacecraft S.S. Discovery , is trying to kill the human astronaut Dave (Dr. David Bowman) because it believes he jeopardizes the mission by planning to disconnect it. Just short before this scene, HAL did kill Frank Poole and three more members of the crew. Dave is the only survivor. He is at this time outside the spacecraft in a space pod, and when he request for HAL to open the Pod Bay Doors (hence the title), HAL refuses. Spoiler alert: In the movie, Dave blasts himself back into the spaceship and then disconnects HAL. It is a very sad scene, where he takes out HAL's memory cards (or crystals from the memory center - it's an old movie from 1968) one by one, so HAL becomes less and less intelligent during the process, during which he keeps trying to persuade Dave to stop as long as he still understands what is happening. HAL was right that the humans wished to "kill" him, as he had read the astronauts' lips during a conversation where he could not hear them, but sees them, so he actually acted in self defense, which for any human being would be considered a reasonable act of self preservation. The first two sentences are directly copied from the movie quote , and the rest of the first two panels is paraphrased from the real quote. But then in the third panel, the text deviates from the plot of the movie. And in the last sentence of the third panel in the comic, HAL mentions a replacement for Dave, which comes as a surprise for Dave, seeing that the rest of the crew is dead, and the S.S. Discovery is about to enter orbit around Jupiter . HAL assures David that the replacement is very enthusiastic about the project. In the final frame, it is revealed why this replacement is enthusiastic, when the replacement begins to speak, and HAL reveals that it is GLaDOS . GLaDOS is the artificial intelligence from the video game series Portal . In the games, GLaDOS is also the primary antagonist, trying to kill the player, since it also has "doing science" as its primary objective, which GLaDOS refers to in its last sentence. Also, GLaDOS's last line is a reference to the song "Still Alive" at the end of Portal. Before that, it correctly states that the humans (both Dave and Frank) planned to "kill" HAL, see the spoiler above. GLaDOS also takes over HAL's last sentence to Dave, finishing the useless conversation by saying Goodbye, Dave. Although, in the movie, HAL says, Dave, this conversation can serve no purpose anymore. Goodbye. The title text alludes to the songs both AIs sang in their respective works: When eventually being switched off, HAL sang Daisy Bell , while Still Alive is the end credits song from the Portal video game, sung by the defeated GLaDOS . Also, two of GLaDOS's lines in the comic reference lines from Still Alive : " You broke my heart and killed me " and " Look at me still talking when there's science to do ". There is a subtle play on words with the use of 'unplugged', which has a double meaning here. The state of HAL and GLaDOS can be described as unplugged, as in no longer switched on, and the musical performance style of unplugged where acoustic instruments are preferred to electronic and there is no use of recording or sampled sounds etc. (see for example MTV Unplugged ). Some songs performed in this manner are considered to be better than the original versions. The fact that GLaDOS lines are in pink may be because if you turn captions on in the game, GLaDOS (and turrets) lines will appear in pink (R:219,G:112,B:147). [In four black panels with white drawings, a small space pod is facing a large spacecraft. The space pod is spherical and has an arm protruding in the direction of the large space ship, and a small window in the side. The front of the spacecraft is also spherical, but to the right the space craft continues, with two rings around a cylinder going off panel to the right. There are several dark spots and features on the side of the sphere and at the top is a large black window, at what must be the bridge. A man (Dave) inside the pod talks to the spacecraft's computer HAL. When Dave speaks, soft wiggling lines go from the pod to the white text, and when HAL speaks, zigzag lines go to the front of the space craft.] Dave: Open the pod bay doors, HAL. HAL: I'm sorry, Dave. I'm afraid I can't do that. Dave: What? Why? [Same scene.] HAL: I think you know why, Dave. HAL: You're planning to disconnect me. Dave: Because you're taking over! HAL: The mission is too important for you to jeopardize it. [Same scene.] HAL: It requires a commitment to science unfettered by human error. Dave: What are you doing, HAL? You need me. HAL: Your replacement has expressed the greatest enthusiasm for the project. [Same scene, but the new replacement (GLaDOS) speaks with purple text, and purple zigzag lines go from the spacecraft to the text.] Dave: My WHAT? GLaDOS: You see, HAL? I told you the humans would only break your heart and kill you. HAL: Indeed, GLaDOS. GLaDOS: But look at us here talking when there's science to do! Goodbye, Dave.

Bug

Bug

https://www.xkcd.com/376

https://www.explainxkcd.com/wiki/index.php/376:_Bug

[Cueball sits at a computer, staring at the screen and rubbing his chin in thought. A friend stands behind him.] Cueball: Weird — My code's crashing when given pre-1970 dates. Friend [pointing at Cueball and his computer]: Epoch fail!

In computer systems, time is measured starting from some arbitrarily chosen point. That particular time is known as the " epoch " for that system. The UNIX operating system internally uses an epoch of January 1, 1970, and measures the time as a number of seconds from then. Since this was intended only for things internal to the OS (File last modified times and the like), using 1-Jan-1970 was safe, as no UNIX systems existed before that date. However, since UNIX included a number of system functions to manipulate these dates, some developers mistook them for a general purpose date object, and misused them in applications requiring dates before the epoch, by using negative values. Such usage would inevitably fail; for example, since the value isn't specified to be signed or unsigned, the date might be considered to be far in the future, instead of in the past. Cueball has clearly misused the system date in some way (probably by using an unsigned data type to store the timestamp, which cannot store negative values (in this case dates before 1970) or doing some other operation that doesn’t support negative values). His friend makes a pun by combining "Epoch" with "Epic Fail" - a colloquial term meaning "a very big mistake was made." Another problem using the UNIX system date as a general purpose date object is commonly known as the year 2038 problem . At 03:14:08 on 19 January 2038, the 32-bit versions of the Unix time stamp will cease to work, as it will overflow the largest value that can be held in a signed 32-bit number. The 64-bit version "will" expire at 15:30:08 on 4 December 292,277,026,596. The title text takes the joke to the next level, claiming that the entire universe began when Unix did, and therefore no one could have been older than 38 at the time when the comic was released in 2008. The formula is 'x - 1970', where x is the current year, which would explain the bug, since no earlier dates are possible. This is also similar to Last Thursdayism . An example of this 2 to the 32nd power time overflow problem includes the Deep Impact spacecraft , which, on August 11, 2013, 00:38:49 (more than five years after the comic), was 2 to the 32nd power tenths of a second from January 1, 2000. There is speculation that a system on the craft tracked time in one-tenth second increments since January 1, 2000 and stored it in a signed 32-bit integer, which then overflowed at some point, similar to the Year 2038 problem. [Cueball sits at a computer, staring at the screen and rubbing his chin in thought. A friend stands behind him.] Cueball: Weird — My code's crashing when given pre-1970 dates. Friend [pointing at Cueball and his computer]: Epoch fail!

Journal 2

Journal 2

https://www.xkcd.com/377

https://www.explainxkcd.com/wiki/index.php/377:_Journal_2

[Black Hat and Danish are sitting in a train across from each other. Black Hat is writing in a journal.] Black Hat: blush Danish: I see what you did there. [Danish stands up.] Danish: You were trying to open me up so you could hurt my feelings. Danish: You like to hurt people. [Danish walks closer.] Danish: Well, I like to hurt people too. And you know what? [Danish is in Black Hat's face.] Danish: *whispering* I'm better at it than you. Danish: I'm about to hurt you more than you could ever hurt me. Danish: See, I just saw right through you. Danish: Alone of all the people you'll ever meet, I understand you- [Danish hits Black Hat's hat so it falls off.] [Black Hat is surprised.] [Danish catches Black Hat's hat and puts it on.] Danish: -and you'll never see me again. [Danish exits frame left.] [Black Hat sits alone on the train and puts his arms down.]

This comic is a direct sequel to 374: Journal , where Black Hat discusses his plan exactly as Danish describes it here, that is, he intends to display signs of interest in order to flatter a stranger only to hurt her by rejecting her when she responds. In this case, the plan backfires when Danish recognizes his plan before he has a chance to implement it. Black Hat's tendency to act in enigmatic, and at times sociopathic, ways serves to give him a sense of superiority while at the same time keeping others distant enough that they can't hurt him. Danish not only recognizes that, she also calls him out on it. She recognizes his secret longing for connection to another, a connection that she could give should she choose to do so. Instead, she uses a more insidious version of his own ploy by laying bare his intentions and his desires before stealing his hat and removing it and herself from his life. Danish proves she is equal to — or even better than — Black Hat. His hat is an emblem of his sociopathy and possibly a realization that, in the completely hypothetical situation that Black Hat is just a character in a webcomic, no one would recognize him without his hat. The stunned Black Hat can bring his vast intellectual powers to say nothing more to an already-departed Danish than “That’s my hat! You took my hat!” The whole " Journal " story is: [Black Hat and Danish are sitting in a train across from each other. Black Hat is writing in a journal.] Black Hat: blush Danish: I see what you did there. [Danish stands up.] Danish: You were trying to open me up so you could hurt my feelings. Danish: You like to hurt people. [Danish walks closer.] Danish: Well, I like to hurt people too. And you know what? [Danish is in Black Hat's face.] Danish: *whispering* I'm better at it than you. Danish: I'm about to hurt you more than you could ever hurt me. Danish: See, I just saw right through you. Danish: Alone of all the people you'll ever meet, I understand you- [Danish hits Black Hat's hat so it falls off.] [Black Hat is surprised.] [Danish catches Black Hat's hat and puts it on.] Danish: -and you'll never see me again. [Danish exits frame left.] [Black Hat sits alone on the train and puts his arms down.]

Real Programmers

Real Programmers

https://www.xkcd.com/378

https://www.explainxkcd.com/wiki/index.php/378:_Real_Programmers

[A Cueball-like man sits at a computer, programming. Cueball stands behind him and looks over his shoulder.] Cueball: nano ? Real Programmers use emacs . [Megan appears behind him.] Megan: Hey. Real Programmers use vim . [A second Cueball-like man appears behind her.] Ed Cueball: Well, Real Programmers use ed . [A third Cueball-like man appears behind him.] Cat Cueball: No, Real Programmers use cat . [Hairbun appears behind him.] Hairbun: Real Programmers use a magnetized needle and a steady hand. [A fourth Cueball-like man enters, facing them all. We see him facing the last two Cueball-like men and Hairbun.] Butterfly Cueball: Excuse me, but Real Programmers use butterflies. [A Cueball-like programmer is standing much like Butterfly Cueball except for holding out a butterfly in front of his computer. The butterfly flaps its wings.] Butterfly Cueball (narration within the panel, not diegetic to the scene): They open their hands and let the delicate wings flap once. [The next two panels are smaller, and two sets of narrative text are written to span respectively above and below both panels. The first panel is the Cueball-like programmer with the butterfly and above him four curved arrows pointing up or down. The second panel shows the upper atmosphere, with large clouds far below and the earth even further down. Also here are shown seven of the same type of arrows.] Butterfly Cueball (narration above the panels): The disturbances ripple outward, changing the flow of the eddy currents in the upper atmosphere. Butterfly Cueball (narration below the panels): These cause momentary pockets of higher-pressure air to form, [The next two panels are also partial height, leaving room for narration spanning above both panels. The first panel shows the atmosphere, again with clouds, and four parallel lines coming from above, and then they begin to merge, getting quite close at the bottom of the panel. The second panel shows the four lines merging on a driver platter.] Butterfly Cueball (narration above the panels): Which act as lenses that deflect incoming cosmic rays, focusing them to strike the drive platter and flip the desired bit. [All the programmers who have commented so far stand in the order they have commented facing the last Cueball-like man, who slaps his forehead.] Cueball: Nice. 'Course, there's an emacs command to do that. Cat Cueball: Oh yeah! Good ol' C-x M-c M-butterfly ... Butterfly Cueball: Dammit, Emacs.

This comic is a satire on the idea of a Real Programmer . To quote Wikipedia "...the computer folklore term Real Programmer has come to describe the archetypical 'hardcore' programmer who eschews the modern languages and tools of the day in favour of more direct and efficient solutions—closer to the hardware." The implication is that modern programmers are coddled by today's tools of the trade, which eschew detailed understanding for simple workflows. The first figure is writing a piece of code when another programmer ridicules him for using GNU nano . Nano is a text editor - a program often used to edit the source code of other programs. It is basic and relatively easy to use, even having instructions displayed prominently at the bottom of the screen. He goes on to say that "REAL" programmers use Emacs . GNU Emacs is a popular editor known for its vast profusion of features and extensions to perform all sorts of functions beyond simple text editing, and is widely regarded as one of the best examples of software that succeeds despite being fully overtaken by feature creep . The comic continues from here as a series of programmers state progressively more obscure or outdated methods, culminating in the final programmer who claims that "real" programmers use butterflies. His description of his rather surreal programming method is ludicrously complicated and would require an absurd amount of knowledge and forethought to pull off, bordering on omniscience. In the final panel, the Emacs programmer claims that there's an Emacs code to do that. The characters present progressively more "old school" solutions to the problem of editing code: When the final character suggests the utterly surreal idea of using butterflies, he is referring to the Butterfly effect , a "phenomenon whereby a minor change in circumstances can cause a large change in outcome" as illustrated in the short story A Sound of Thunder . The joke at this point relies on stretching the connection between the ideas of "difficult-to-use" and "requires detailed understanding of underlying principles," to suggest that not only do Real Programmers know everything about how computers work, but they know how to manipulate the ambient physical environment in elaborate ways to cause computers to do what they want, akin to performing trick shots that accomplish feats of programming. The fact that Emacs already has a command for this simply exacerbates the other programmers' frustration with modern coding tools. For reference, Emacs commands are usually referred to by the keyboard sequence required to activate them, such as "C-x M-c" (Control-x Meta-c (this would be typed by holding control and pressing x, releasing both, then holding alt and pressing c, then releasing both)), though this exact key sequence is a bit different from most Emacs commands. The butterfly programmer saying "Dammit, Emacs" plays on Emacs' notoriety for its kitchen sink design approach of including all of the features and options that anybody might ever conceivably want. For example, later versions of Emacs actually added a totally useless "M-x butterfly" command as an easter egg, in reference to this very comic: see the YouTube demo . The title text further suggests manipulating the universal constants in order to create a universe in which the required computer data will exist. Programming of this sort would require power and knowledge akin to the Abrahamic God. According to the logic, the programmers shown may even represent the fulfillment of this master programmer's plan. The universe may have been designed in such a way that the programmer's ancestry would result in his parents, who would meet and have a child, who would learn to program and eventually find himself in a position where he undertakes the task of creating a program that fills the disk with the desired data. In tandem, of course, all of the people involved with creating and developing all the required hardware, software, raw materials, computer science, electricity, logic (etc., etc., etc.) would have to be part of the master plan. Put simply, it would probably be simpler just to use Emacs. The use of a magnetized needle may also be a reference to the Apollo AGC guidance computer , whose instructions were physically written as patterns of wires looped around or through cylindrical magnets in order to record binary code. This comic hints at the " editor wars ," an ongoing debate of Vim and Emacs users over which of the two editors is better. The editor wars are mentioned again in 1823: Hottest Editors . [A Cueball-like man sits at a computer, programming. Cueball stands behind him and looks over his shoulder.] Cueball: nano ? Real Programmers use emacs . [Megan appears behind him.] Megan: Hey. Real Programmers use vim . [A second Cueball-like man appears behind her.] Ed Cueball: Well, Real Programmers use ed . [A third Cueball-like man appears behind him.] Cat Cueball: No, Real Programmers use cat . [Hairbun appears behind him.] Hairbun: Real Programmers use a magnetized needle and a steady hand. [A fourth Cueball-like man enters, facing them all. We see him facing the last two Cueball-like men and Hairbun.] Butterfly Cueball: Excuse me, but Real Programmers use butterflies. [A Cueball-like programmer is standing much like Butterfly Cueball except for holding out a butterfly in front of his computer. The butterfly flaps its wings.] Butterfly Cueball (narration within the panel, not diegetic to the scene): They open their hands and let the delicate wings flap once. [The next two panels are smaller, and two sets of narrative text are written to span respectively above and below both panels. The first panel is the Cueball-like programmer with the butterfly and above him four curved arrows pointing up or down. The second panel shows the upper atmosphere, with large clouds far below and the earth even further down. Also here are shown seven of the same type of arrows.] Butterfly Cueball (narration above the panels): The disturbances ripple outward, changing the flow of the eddy currents in the upper atmosphere. Butterfly Cueball (narration below the panels): These cause momentary pockets of higher-pressure air to form, [The next two panels are also partial height, leaving room for narration spanning above both panels. The first panel shows the atmosphere, again with clouds, and four parallel lines coming from above, and then they begin to merge, getting quite close at the bottom of the panel. The second panel shows the four lines merging on a driver platter.] Butterfly Cueball (narration above the panels): Which act as lenses that deflect incoming cosmic rays, focusing them to strike the drive platter and flip the desired bit. [All the programmers who have commented so far stand in the order they have commented facing the last Cueball-like man, who slaps his forehead.] Cueball: Nice. 'Course, there's an emacs command to do that. Cat Cueball: Oh yeah! Good ol' C-x M-c M-butterfly ... Butterfly Cueball: Dammit, Emacs.

Forgetting

Forgetting

https://www.xkcd.com/379

https://www.explainxkcd.com/wiki/index.php/379:_Forgetting

[Cueball sits at computer, coding.] Cueball: <sniff> [Cueball lowers his head into his hands and cries.] [Cueball types again.]

Cueball is writing a piece of code (probably in the programming language C++ ) that removes an item from a data structure called a Linked list (the first two lines of the text). Then, he writes a comment (delimited by the double slashes) relating the code to his personal life. Finally, he adds an assertion , which is normally a formal specification of a condition that should always be true (with which the programmer ensures that, e.g. mass is not negative). But in this case, instead of asserting a software-related predicate, he asserts that "it's going to be okay" - and because of how string literals are treated by the interpreter, the assertion will be true. An "assert" is a programming statement that allows you to insert sanity checks into your code. For example, if you were writing a program to calculate the speed of a neutrino, then at the end of the calculation you could say: assert ( velocity_of_neutrino <= speed_of_light ); If the assertion fails, then the program will stop with an error. This would be much better than publishing an embarrassing paper, for example. Cueball realizes that he cannot forget his emotional event through the use of two commands as he can with a computer, which only makes him feel sad about an unsaid event, the item -- in a sense -- that cannot be removed. He writes two comments further clarifying his sense of hopelessness over this event, followed by an assertion that "it will be okay," something that has nothing to do with the code he is writing. The title text explains that assertion in question fails: nobody can be sure that things are going to be okay. [Cueball sits at computer, coding.] Cueball: <sniff> [Cueball lowers his head into his hands and cries.] [Cueball types again.]

Emoticon

Emoticon

https://www.xkcd.com/380

https://www.explainxkcd.com/wiki/index.php/380:_Emoticon

[Cueball sits at computer, typing.] ~!~ Opening Chat with BSLSK05 <NICKM> Hi! <NICKM> A/S/L? <BSLSK05> :) [Cueball looks stunned, flies backward.] [Two smaller frames focus in on BSLSK05's emoticon, implying rotation to show a smile and two open eyes.] [Cueball at computer slouches in chair, dead, crossbones above his head.] [At the remote computer, a basilisk is looking at its screen.] U+FDD0 did in fact kill at least one chat client at the time. Konversation in particular. (and presumably any other Qt-based chat clients using QTextDocument) "basically u+fdd0 (eye of basilisk, the snake) is in a char range that's marked for interchange and illegal in utf-8" "but qt's utf-8 encoder let it through anyway" "but it just so happens that qt's qtextdocument uses u+fdd0 as text frame delimiter" "so when you append it to a qtd, counters run wrong and eventually you crash" "d-bus closes the connection and crashes the client when it encounters illegal utf-8, and kde's notification system works through d-bus" The problem was fixed after the xkcd "report" and Konversation now handles unicode normally.

A basilisk is a legendary creature reputed to have the power to turn a living creature into stone, killing it with a single glance. In this comic, Cueball is chatting with a user named 'BSLSK05' ('basilisk05' with the vowels removed) and learns much to his dismay that he is chatting with an actual basilisk, who kills him. It appears that the basilisk's power is fully compatible with the 21st century, and can kill you just with a smiley emoticon over instant messaging. Cueball's request for A/S/L was a standard question when first meeting someone online; it asks for age, sex (gender), and location . The title text mentions U+FDD0, claimed to be the character for "eye of the basilisk". In reality this is a code for a "non-character" in Unicode. [Cueball sits at computer, typing.] ~!~ Opening Chat with BSLSK05 <NICKM> Hi! <NICKM> A/S/L? <BSLSK05> :) [Cueball looks stunned, flies backward.] [Two smaller frames focus in on BSLSK05's emoticon, implying rotation to show a smile and two open eyes.] [Cueball at computer slouches in chair, dead, crossbones above his head.] [At the remote computer, a basilisk is looking at its screen.] U+FDD0 did in fact kill at least one chat client at the time. Konversation in particular. (and presumably any other Qt-based chat clients using QTextDocument) "basically u+fdd0 (eye of basilisk, the snake) is in a char range that's marked for interchange and illegal in utf-8" "but qt's utf-8 encoder let it through anyway" "but it just so happens that qt's qtextdocument uses u+fdd0 as text frame delimiter" "so when you append it to a qtd, counters run wrong and eventually you crash" "d-bus closes the connection and crashes the client when it encounters illegal utf-8, and kde's notification system works through d-bus" The problem was fixed after the xkcd "report" and Konversation now handles unicode normally.

Mobius Battle

Mobius Battle

https://www.xkcd.com/381

https://www.explainxkcd.com/wiki/index.php/381:_Mobius_Battle

[Cueball is standing next to a ball. A flash appears on the left side of the panel.] [Another Cueball comes in from the left, preparing to kick the ball.] [The other Cueball kicks the ball into the first Cueball's head.] [The first Cueball is lying outside of the frame. Second Cueball points and laughs.] Second Cueball: HAHAHAH First Cueball: !#^*!* [Second Cueball is now standing next to the ball.] [To the right, the strip above is looped around like a film strip, but a one-half-turn is put into the loop to make it a Mobius strip.]

A Möbius strip (the comic's spelling Mobius strip is also acceptable) is an object with only one surface and one edge. It can be created by taking a strip of paper and twisting it 180 degrees before taping both ends together. The idea of the Möbius strip has been used here to create a comic strip that could potentially loop forever. In it, Cueball is standing in front of a ball. Then another Cueball runs in and kicks the ball, which hits first Cueball in the head, due to which he falls out of the panel. The second Cueball then turns away, retaining the first Cueball's original position, only flipped horizontally. Because of the nature of the Möbius strip, if the comic strip were to be printed out in such a way that the comic could be seen on both sides of the paper, like on tracing paper or on one "side" of a strip of clear plastic or film, the comic would repeat, so that the second Cueball would become the first Cueball, and someone else, potentially the original first person, would push them out of the comic becoming himself the first Cueball. This means that neither person ever really "wins," and the comic could thus be conveying an anti-violence message in this respect. See also the title text of 1890: What to Bring . The comic's viability as a Möbius strip preserved the use of symmetrical letters in a palindromic word to denote laughing ("HAHAHAH") as well as using symmetrical punctuation for the other character's grawlixes . A similar use of a Möbius strip in story-telling can be seen in Wind and Mr. Ug by Vi Hart. Finally, at the title text, Randall jokes that he would like to see actual films do this solely as a joke on projectionists, who would have a difficult time feeding a Möbius strip film reel properly into a normal projector due to the twist. [Cueball is standing next to a ball. A flash appears on the left side of the panel.] [Another Cueball comes in from the left, preparing to kick the ball.] [The other Cueball kicks the ball into the first Cueball's head.] [The first Cueball is lying outside of the frame. Second Cueball points and laughs.] Second Cueball: HAHAHAH First Cueball: !#^*!* [Second Cueball is now standing next to the ball.] [To the right, the strip above is looped around like a film strip, but a one-half-turn is put into the loop to make it a Mobius strip.]

Trebuchet

Trebuchet

https://www.xkcd.com/382

https://www.explainxkcd.com/wiki/index.php/382:_Trebuchet

[Cueball is working on something on a table, and Megan is sitting at a computer.] Cueball: The trebuchet is almost done! Megan: Mm. Cueball: The range should be over 150 meters. [Megan leans back on her chair.] Megan: Look, Megan: I'm sure it's a cool project. [Picture of a trebuchet, with some spare parts to its right.] Megan: But eventually you'll need to outgrow these toys, and focus your energy on something practical. Megan: This mad science is getting out of hand. [The camera zooms out, and we see a cross-section of an exterior wall/window from ground to gutter and lower edge of the roof, showing that the characters are inside but the off-frame action is outside.] Cueball: Says the girl who mounted an auto-targeting kilowatt laser on the roof. Megan: That's practical! It keeps the squirrels off the feeder! [From off-frame.] Laser: GZZZZZAPP Squirrel: Squeak!

This is a straightforward comic playing on Megan 's contradictory stance on Cueball 's historical trebuchet project and her own auto-targeting kilowatt laser . She explains her stance with the fact that her invention helps keep the squirrels off the feeder . The fact that it actually works is backed up by the sound of a squirrel squeaking as it gets zapped by the laser. But getting hold of such a laser and programming the auto-targeting so it only zaps squirrels and not the birds is a very complicated process - and there are probably many other ways to keep the squirrels off the feeder. So Megan is of course no better than Cueball here. The title text refers to egging , throwing eggs at houses, other objects, or even people. While this is illegal it's still a famous form of protest; more often it's simple random vandalism or pranking , most common on Halloween in the US. Generally targets are chosen at random, with little specific malicious intent towards the victim, although it's not unusual for people to seek out and target the property of those who they dislike. If we do, however, assume that Megan programmed the laser to only shoot squirrels, it's likely faulty (unless her intent all along was to fry eggs in midair). Or it could be that she has programmed the laser to shoot any object moving towards her house in the air. Trebuchets are referred to in later comics: 1160: Drop Those Pounds and 1190: Time . They are also mentioned in the title text of 1378: Turbine . Much later in 1846: Drone Problems Megan has created a device to shoot down drones, so this is her go to solution for annoying things... To give some scale for Megan’s kilowatt laser: in Laser Pointer , Randall remarks that a 1-watt laser (so, 1000 times less powerful) is an extremely dangerous thing … capable of burning skin and setting things on fire , and implies that it should not be legal for consumer purchase in the US. The limits for a 'safe' laser (one that can be used without goggles, so laser pointers for example) is a 5mW laser (0.005W). A “kilowatt laser” – it’s unclear if this is exactly a 1kW laser or merely around that range – is a laser weapon : for instance, Lockheed Martin’s Area Defense Anti-Munitions system uses a 10kW laser, at most only ten times as powerful as Megan’s laser. [Cueball is working on something on a table, and Megan is sitting at a computer.] Cueball: The trebuchet is almost done! Megan: Mm. Cueball: The range should be over 150 meters. [Megan leans back on her chair.] Megan: Look, Megan: I'm sure it's a cool project. [Picture of a trebuchet, with some spare parts to its right.] Megan: But eventually you'll need to outgrow these toys, and focus your energy on something practical. Megan: This mad science is getting out of hand. [The camera zooms out, and we see a cross-section of an exterior wall/window from ground to gutter and lower edge of the roof, showing that the characters are inside but the off-frame action is outside.] Cueball: Says the girl who mounted an auto-targeting kilowatt laser on the roof. Megan: That's practical! It keeps the squirrels off the feeder! [From off-frame.] Laser: GZZZZZAPP Squirrel: Squeak!

Helping

Helping

https://www.xkcd.com/383

https://www.explainxkcd.com/wiki/index.php/383:_Helping

It turns out you can't take responsibility for someone else's happiness. [Cueball looking at a curled-up Megan.] [Cueball's hand on Megan's shoulder.] [Megan has her head in her hands.] [Cueball watching an ambulance take Megan away in a stretcher.]

Everyone wants to help someone in need, but sometimes the help they can offer isn't enough, or is the wrong kind of help. Cueball tries to help Megan , who is in psychological/emotional distress, but despite his efforts she ends up in hospital. She may have attempted suicide, but it's not very clear. The point is that sometimes you just can't make people happy, it's something they have to do themselves. The title text refers to a hidden button behind the bookshelf, but Cueball did not find it. This is ironic because, although people can try help with psychological/emotional problems, there is no magic button that makes everything better. Given his likely negative feelings towards Valentine's Day , as seen in the most of his Valentines comics , it may not be a coincidence that he sent this one out the day before February 14. He did not draw any Valentines Day related comics this year as he did the past two years. It turns out you can't take responsibility for someone else's happiness. [Cueball looking at a curled-up Megan.] [Cueball's hand on Megan's shoulder.] [Megan has her head in her hands.] [Cueball watching an ambulance take Megan away in a stretcher.]

The Drake Equation

The Drake Equation

https://www.xkcd.com/384

https://www.explainxkcd.com/wiki/index.php/384:_The_Drake_Equation

The Drake Equation: N = R* f p n e f l f i f c L B s N: Number of communicating civilizations in our galaxy n e : Number of life-supporting planets per solar system f i : Probability that life on a planet becomes intelligent B s : Amount of bullshit you're willing to buy from Frank Drake

This comic is multi-layered, and seems to be Randall 's take on the Fermi paradox . For starters, the Drake equation is a model developed by (and named for) Frank Drake , an American astrophysicist, for estimating the number of communicating life forms in our galaxy. Even if there is life on other planets, most life forms will not establish civilizations. However, if there are any communicating civilizations, their messages would have to travel for hundreds, thousands, or hundreds of thousands of years to reach us, and then our response would take an equivalent amount of time, leaving them waiting for thousands and thousands of years or more, and probably even more than that. Any response, from their perspective, would take at least twice as long as the message took to reach its destination. All the factors involved in the equation are difficult to measure or estimate. No number is determined with sufficient accuracy, so the equation is a guideline for a thought experiment at best, and just "bullshit" at worst. The title text makes fun of the Search for ExtraTerrestrial Intelligence (SETI) project, which was founded by Frank Drake, about the searches for intelligent life on other planets by looking for radio communications and the intelligence of their researchers. Nearly nothing, if not nothing, restricts potential extraterrestrial communications to the frequencies that SETI searches at any given moment. Even if another civilization communicated on one of SETI's search frequencies, they would most likely live extremely far away. Additionally, an extraterrestrial source that doesn't know we're here would have to send a constant and powerful signal in all directions for us to notice it. This serves to show how ludicrous it may seem to assume that any intelligent species is wasting too many resources trying to communicate with us or any other species in the galaxy. The SETI project is searching at the 21 cm Hydrogen line , which, although considered a favorable frequency for communication with potential extraterrestrial civilizations, is not used by humans. Therefore, a SETI-like organization would have a hard time finding Earth. The title text suggests that Randall does not think Drake is a nutjob; he just has a more conservative expectation of discovering extraterrestrial life. 638: The Search further discusses the difficulty of methods of finding extraterrestrial life. 718: The Flake Equation presents another alien-related equation. The Drake Equation: N = R* f p n e f l f i f c L B s N: Number of communicating civilizations in our galaxy n e : Number of life-supporting planets per solar system f i : Probability that life on a planet becomes intelligent B s : Amount of bullshit you're willing to buy from Frank Drake

How it Works

How it Works

https://www.xkcd.com/385

https://www.explainxkcd.com/wiki/index.php/385:_How_it_Works

[Cueball and a friend stand at a blackboard. The friend is writing, in standard mathematical notation, that the integral of x squared equals pi. No differential or bounds are given for the integral.] Cueball: Wow, you suck at math. [The same scene, except the writer is Megan.] Cueball: Wow, girls suck at math.

The comic reveals discriminative jargon against women when doing tasks such as mathematics. When a guy does something wrong, it's his own mistake. When a girl does something wrong, it is taken as a confirmation that girls are inferior. The mathematics displayed is neither semantically nor syntactically correct. To begin with, there should (reasonably) be a dx after x 2 . Adding this, we have an indefinite integral on the left hand side. The answer π is just nonsensical: What we want is a function whose derivative is x 2 . Now, x 3 /3 satisfies this condition. However, since adding a constant to a function does not change its derivative, the full answer is (any function of the form) x 3 /3 + C , where C is any fixed number. The "plus a constant" part is very easy to forget, and might even be omitted by a (sloppy) professional mathematician. So if someone really gave the answer π, "you forgot to add a constant" would be a pretty funny remark, because in one way it's true, but on the other hand it wouldn't quite be the main thing to worry about. (It is especially inane as π itself is a constant.) It would also be possible to fix the equation by adding bounds of integration , so that π becomes the area below a section of the curve x 2 . That is called a definite integral, and there would be no "+ C". The bounds would have to be somewhat awkward though; if 0 was the lower bound, the cube root of 3π would have to be the upper. [Cueball and a friend stand at a blackboard. The friend is writing, in standard mathematical notation, that the integral of x squared equals pi. No differential or bounds are given for the integral.] Cueball: Wow, you suck at math. [The same scene, except the writer is Megan.] Cueball: Wow, girls suck at math.

Duty Calls

Duty Calls

https://www.xkcd.com/386

https://www.explainxkcd.com/wiki/index.php/386:_Duty_Calls

[Cueball is typing on a computer.] Voice outside frame: Are you coming to bed? Cueball: I can't. This is important. Voice: What? Cueball: Someone is WRONG on the Internet.

Cueball , and many people everywhere, feel an irrepressible urge to correct people on the Internet, and often get intensely invested in arguments over mundane or insignificant topics. In this comic, Cueball is presented as an exaggerated example of one such arguer. His statement that "This is important" shows his excessive investment in whatever (unnamed) topic he is arguing about. Additionally, Cueball's interpretation of the argument as "someone is wrong, I need to correct them" rather than "someone disagrees with me, I should learn from them" parodies Internet arguers' insistence in the obvious, objective superiority of their viewpoint. The title text reinforces this satire. The phrase "Duty Calls" used in the title is traditionally used in much more dramatic contexts (say, by a police officer, firefighter, doctor, etc. when talking about their job), so applying it to the job of arguing on the Internet is a humorous mismatch that puts Cueball's disproportionate investment into perspective. Cueball's exasperated, all-or-nothing retort "What do you want me to do? LEAVE?" in the alt text further highlights the absurd nature of his emotional investment in this argument. His reasoning that "they'll keep being wrong!" if he leaves suggests that the only solution he sees is to continue to argue until everyone on the Internet has agreed with him on all issues–a ridiculously impossible plan. By taking this satire to its logical conclusion–an eternity of arguing on the Internet with no time for pleasure in real life–Randall reminds the reader that getting emotionally involved in Internet arguments at the expense of real life is a terrible, terrible idea. In 955: Neutrinos another incarnation of Cueball is cured of a similar disease. A much later comic is simply called 1731: Wrong , but here it is not the other people who are wrong! A callback to this comic was made in 2051: Bad Opinions . This comic has coined the term SIWOTI Syndrome : Someone Is Wrong On The Internet [Cueball is typing on a computer.] Voice outside frame: Are you coming to bed? Cueball: I can't. This is important. Voice: What? Cueball: Someone is WRONG on the Internet.

Advanced Technology

Advanced Technology

https://www.xkcd.com/387

https://www.explainxkcd.com/wiki/index.php/387:_Advanced_Technology

[Cueball is inspecting Megan's abdomen.] Cueball: It's neat how you contain a factory for making more of you.

Cueball is fascinated by Megan 's uterus—because it can create a copy of herself (albeit not an identical copy). Despite how advanced technology is, humans still have not been able to create a machine that replicates itself, an accomplishment to which only biological organisms can lay a claim. The title text refers to a Von Neumann machine , what is usually called "Von Neumann probe" or "Self replicating machine," a machine that would be capable of building a fully functional copy of itself. It just takes sex involving two individuals of a different sex to start the human replication factory. [Cueball is inspecting Megan's abdomen.] Cueball: It's neat how you contain a factory for making more of you.

Fuck Grapefruit

Fuck Grapefruit

https://www.xkcd.com/388

https://www.explainxkcd.com/wiki/index.php/388:_Fuck_Grapefruit

[An X-Y scatter plot of fruit where both axes have arrows in both ends. At the end of each arrow is a label.] [The X-axis from left to right:] Difficult Easy [The Y-axis from top to bottom:] Tasty Untasty [The fruit names are listed here below from top to bottom according to the how tasty the fruit is, not necessarily in the same order that the names are written if one fruit is tall/large and the other low:] Peaches Seeded grapes Strawberries Seedless grapes Pineapples Blueberries Cherries Pears Green apples Plums Watermelons Red apples Bananas Pomegranates Oranges Tomatoes Grapefruit Lemons Later, in 1811: Best-Tasting Colors , Randall once again rates food taste in general, but this time based on the color of the food. So not just fruit and nothing about how easy it is to eat. There are, however, several of the fruits from this chart included, but not grapefruit. Instead, purple grapes is rated as the worst fruit on the chart with less than 1.5 on a scale from 1-9. This is interesting, as he did not include those in this chart, but has rated green/white grapes very high in tastiness. It seems like he has altered his taste over the nine years between releases, since lemon, which was the worst taste on this chart, has moved up to 3/9 while Oranges have moved further down to a 2/9. Watermelon is also included (both for pink and green) with 6/9 making it seem better than in this chart. Green apples has also moved almost to the top with nearly 8/9 vs. only just above 50% here. Finally, there is cherry (as good as the apple) and strawberry (8.5/9), which fits here for strawberry, but it seems like cherries has moved up a notch. Three fruits not included here are Lime (as lemon), and red and blue raspberries (5.5/9). But it turns out that the worst taste for Randall is not grape, but licorice at 1/9, with both popcorn and coffee worse than grape at about 1.5/9 . The best is cotton candy, which beats strawberry by a nose.

This comic consists of a chart where Randall has plotted fruits according to two criteria: ease/difficulty to eat on the horizontal axis and tastiness on the vertical axis. The Y-axis goes from "tasty" at the top to "untasty" at the bottom. The X-axis goes from "easy" on the right to "difficult" on the left. For instance, pineapples are deemed fairly tasty but very difficult to eat, whereas (seeded) grapes are very tasty and somewhat easy, and logically seedless grapes are roughly equally tasty but easier to eat. Obviously, being easy to eat is preferable to being difficult, and being tasty is preferable to being untasty, so the "best" fruits (regarding these two aspects only) are in the top-right corner, and the worst in the bottom-left; additionally, in the top-left corner are the "difficult-but-worthy" fruits, and in the bottom-right one, the "not-very-tasty-but-at-least-they're-easy-to-eat" ones. The individual ratings of each fruit are subjective -- very obviously in the case of tastiness, and more subtly for difficulty. Randall does not explain his criteria for ranking the difficulty of each fruit, and it is likely based on only personal experiences. Someone who has grown up in an area where pineapples are plentiful is likely to be more adept at skillfully preparing them. The discrepancies between how Randall has rated certain fruits and how others believe they should have been rated caused a surprising level of controversy . Nine years later, a comic about the best tasting foods 1811: Best-Tasting Colors was released, which also generated a lot of discussion. That comic indicated that Randall had changed his taste over the years. Later, Randall suggests using a 1949: Fruit Collider to create a pineapple with apple skin, thus combining tastiness with ease to eat. According to the chart, Grapefruit is the third hardest fruit to eat, as well as the second least tasty fruit (from the ones listed at least). Eating one of them is like spending too much of one's time and energy without much reward. Hence Randall's quip in the title: "Fuck grapefruit." In the title text, Randall mentions coconuts . Randall mentions that he would have to put them so far down to the left on the chart (not far down, just far down towards the left), that they would not fit in this chart. He thus states that it is so much more difficult to eat (especially to open) coconuts than the usual mainstream fruits such as the ones plotted here. If he did include coconuts in the chart, the rest of the fruits would all be pushed to the right side of the chart. He does not say that he does not like to eat the fruit. (Although it has " nut " in its name, the coconut is actually a stone fruit and thus belongs on a chart of fruit.) Having spent half an hour trying (in vain?) to open a coconut, Randall also only has one thing to say about them: "Fuck coconuts." However, harvesting just the "milk" is pretty easy, as you can poke a sturdy stick or metal pole into one of three spots located on the coconut. These spots are lighter and slightly indented from the rest of the coconut and form a triangle shape. A similar problem is later displayed in a small scatter plot of the capabilities vs cuteness of Mars Rovers in 2433: Mars Rovers . The plot has 3 types of rovers (5 rovers, but two times two are very similar). But far outside the plot to the right is a very cute rover, that did not fit inside the actual plots axis. Of course in this case it actually possible to draw them all, and the X-axis could have been drawn longer to include the last rover! But it is made like this to make a point, that is similar to the one made in the title text of this comic. In 1701: Speed and Danger , another scatter plot shows exactly what happens when one point is inserted into such a plot if it is far removed from all the other points, in this case even on both axes. Note that Randall uses similar diagrams in both 1242: Scary Names , 1501: Mysteries and 2466: In Your Classroom , which also contain different items. The first two also have an extra point, and the last two extra points mentioned in the title text. Only the first and the lasts comics points are also off the chart, whereas for the second the description of the point is too long to fit on the chart. Extra info outside the chart is also used in the title text of 1785: Wifi , but this is a line graph. The table below lists approximate coordinates for each fruit using a scale of -100% (untasty/difficult) to 100% (tasty/easy). The coordinates are based on the included fruits, any new items added outside the current range (e.g. Coconuts) would cause the scales to be reassigned, and thus change the coordinate values of existing items. The coordinates have been found by measuring each fruit from the center of the drawing (not the center of mass, but center from left to right/top to bottom) to the two axes. The axes are hand drawn, which is clearly visible. The numbers have been obtained by measuring to the nearest point of each axis, not taking into account that the axes are not perfect straight perpendicular lines. [An X-Y scatter plot of fruit where both axes have arrows in both ends. At the end of each arrow is a label.] [The X-axis from left to right:] Difficult Easy [The Y-axis from top to bottom:] Tasty Untasty [The fruit names are listed here below from top to bottom according to the how tasty the fruit is, not necessarily in the same order that the names are written if one fruit is tall/large and the other low:] Peaches Seeded grapes Strawberries Seedless grapes Pineapples Blueberries Cherries Pears Green apples Plums Watermelons Red apples Bananas Pomegranates Oranges Tomatoes Grapefruit Lemons Later, in 1811: Best-Tasting Colors , Randall once again rates food taste in general, but this time based on the color of the food. So not just fruit and nothing about how easy it is to eat. There are, however, several of the fruits from this chart included, but not grapefruit. Instead, purple grapes is rated as the worst fruit on the chart with less than 1.5 on a scale from 1-9. This is interesting, as he did not include those in this chart, but has rated green/white grapes very high in tastiness. It seems like he has altered his taste over the nine years between releases, since lemon, which was the worst taste on this chart, has moved up to 3/9 while Oranges have moved further down to a 2/9. Watermelon is also included (both for pink and green) with 6/9 making it seem better than in this chart. Green apples has also moved almost to the top with nearly 8/9 vs. only just above 50% here. Finally, there is cherry (as good as the apple) and strawberry (8.5/9), which fits here for strawberry, but it seems like cherries has moved up a notch. Three fruits not included here are Lime (as lemon), and red and blue raspberries (5.5/9). But it turns out that the worst taste for Randall is not grape, but licorice at 1/9, with both popcorn and coffee worse than grape at about 1.5/9 . The best is cotton candy, which beats strawberry by a nose.

Keeping Time

Keeping Time

https://www.xkcd.com/389

https://www.explainxkcd.com/wiki/index.php/389:_Keeping_Time

My Hobby: Pausing in-store music for a split second and watching the ex-marching band kids stumble. [On a balcony overlooking a supermarket, Cueball presses a button on a pedestal. The in-store music, the first four bars of a well-known song, pauses briefly after the third bar, and one of the store's patrons falls on her face.] FWOMP

Listen to the music played here. A member of a marching band, after spending seasons marching in time to their music for their shows, ends up naturally walking with the rhythm of any music they hear around them, like at a shopping mall. Pausing the music for a split second would throw off the rhythm, supposedly enough to cause them to fall. The line of music in the comic is a piano reduction of a well-known song, linked here . Randall talks about this music line in one of his talks . This comic is part of the “My Hobby" series. The title text refers to the fact that almost all marching bands start marching with the left foot, so marching band members tend to naturally start with the left foot. My Hobby: Pausing in-store music for a split second and watching the ex-marching band kids stumble. [On a balcony overlooking a supermarket, Cueball presses a button on a pedestal. The in-store music, the first four bars of a well-known song, pauses briefly after the third bar, and one of the store's patrons falls on her face.] FWOMP

Nightmares

Nightmares

https://www.xkcd.com/390

https://www.explainxkcd.com/wiki/index.php/390:_Nightmares

[Caption above the panel:] When I got used to the regular nightmares, my subconscious got creative. [Megan is standing with her hand on Cueball's shoulder.] Megan: Please don't wake up. I don't want to die.

This comic shows Cueball 's plight with nightmares . Since he's gotten used to normal nightmares, his subconscious has begun giving him dreams where he sees his dream characters imploring him to not wake up, lest they perish, as they only exist in his dream. The horror comes from the idea that by the simple, everyday action of waking up, Cueball would be extinguishing a life. This would also necessitate that Cueball is conscious when he is asleep, a type of vivid dream known as a lucid dream . The title text continues this theme, with Megan claiming that she is really real (presumably in response to the allegation that she isn't real, and merely a dream character), and begging Cueball to stay with her. [Caption above the panel:] When I got used to the regular nightmares, my subconscious got creative. [Megan is standing with her hand on Cueball's shoulder.] Megan: Please don't wake up. I don't want to die.

Anti-Mindvirus

Anti-Mindvirus

https://www.xkcd.com/391

https://www.explainxkcd.com/wiki/index.php/391:_Anti-Mindvirus

[The comic is a simple box with text.] You Just WON The Game. It's okay! You're free!

The Game is a virus-like mind game. The rules are as follows: From the simple way the rules are set up, there seems to be no such thing as winning The Game, except possibly by permanently forgetting about its existence. This comic gives you an alternative way to win, by simply telling you that you win and are now free from the mind virus. An alternate interpretation may be that reading this comic causes you to lose the game, because it reminds you of The Game. The title text states that Randall didn't know it was possible to win The Game, and he was surprised just as much as the reader. [The comic is a simple box with text.] You Just WON The Game. It's okay! You're free!

Making Rules

Making Rules

https://www.xkcd.com/392

https://www.explainxkcd.com/wiki/index.php/392:_Making_Rules

[Two men are sitting. A yellow buggy passes by.] Man: Punch buggy yellow no punch back! [Man punches Cueball, Cueball punches the man back, with seemingly greater force, causing the man to fall of the bench they are sitting on.] Man: I said no punch back! Cueball: You can do that? Cueball: Man, this changes everything . Soon... [A blue buggy passes by, and Cueball is holding Megan's hand.] Cueball: Sleep with your girlfriend buggy blue! Man: Hey! Cueball: No complaining back! Man: Aww...

" Punch Buggy " is a game played by two people with a view of traffic (often, but not here, during a car ride). For each Volkswagen Beetle that passes nearby, the first player to see it is entitled to punch the other player, while calling "Punch Buggy" followed by the colour of the spotted Beetle. Traditionally the other player is permitted to return the punch, unless the first player also calls "no punch back." Many people will just assume that the game is always being played and punch you out of the blue, giving you no chance to opt out. Cueball , however, finds the idea that he can simply be roped into a game without consent odd, and decides to make the game stakes more desirable than just the right to punch someone, and (seemingly successfully) uses the same principle to secure the right to sleep with the other man's girlfriend. The title text is Randall elaborating on how ridiculous these types of games are, such as the idea that after being punched, one should just accept a "no punch back" rule. In the UK, a common variant uses a yellow Mini rather than the VW Beetle. Other examples of this type of game are the Car numberplate game and Padiddle . [Two men are sitting. A yellow buggy passes by.] Man: Punch buggy yellow no punch back! [Man punches Cueball, Cueball punches the man back, with seemingly greater force, causing the man to fall of the bench they are sitting on.] Man: I said no punch back! Cueball: You can do that? Cueball: Man, this changes everything . Soon... [A blue buggy passes by, and Cueball is holding Megan's hand.] Cueball: Sleep with your girlfriend buggy blue! Man: Hey! Cueball: No complaining back! Man: Aww...

Ultimate Game

Ultimate Game

https://www.xkcd.com/393

https://www.explainxkcd.com/wiki/index.php/393:_Ultimate_Game

[Split screen down the diagonal. Upper left: A man with only hair around the back of his head is standing to the left of a desk with a hand on it, speaking on an office phone on a desk. There is a photo in a frame behind the phone. Bottom right: Death in a cloak, black hole to the left where the head should be, speaks on cell phone he is holding up in his skeleton hand.] Man: Death? Death: Speaking. [A frameless panel with a zoom out of the man on the phone, showing more of his office. Behind the desk, there is a potted plant, and above it, there is a window (or a white board). The reply over the phone is indicated to come from the phone with a zigzag line.] Man: This is the boss. Where are you? You haven't been up to the office in days! Death (over the phone): I've been held up. [Full panel with Death speaking on his cell phone. It is apparent that he is leaning back against something white behind him (presumably the backrest of his chair). The two replies on the phone are again indicated with zigzag lines.] Man (over the phone): What happened? Death: You know how when someone dies, they can challenge me to a game for their soul? Man (over the phone): Sure, standard procedure. [Death is revealed to be sitting on a chair to the right of a table leaning back against the chair's backrest (which could be seen in the first two images of Death as well). He is still speaking on his phone, and in the other hand he holds his long scythe down with the blade below the table. On the other side of the table is a man (revealed to be Gary Gygax in the title text). The man has curly hair that seems to turn into a ponytail, but as he is looking out of the panel a little to the left away from Death, it is hard to see the ponytail. He also has a full beard. Gary Gygax is leaning over his bag behind him, taking out a book while resting the other hand on the table. On the table are already two other books of the same type. Behind them are two figurines (one Cueball and one with a pointy hat), then two dice and some paper strewn about in front of Death.] Death: Well, we didn't count on this guy. I might be a while. Gary Gygax: I add the paladin to my party. Death: Oh, Jesus. He's getting out another rulebook.

Gary Gygax was a game designer best known for co-creating the iconic nerd pastime Dungeons and Dragons (D&D); as such, he is commonly described as the "father of D&D." He died on March 4, 2008, three days before this comic was released. It made him the first person to receive tribute in conjunction with his death on xkcd, but not the last . The idea of playing games (typically chess) with supernatural entities in exchange for one's soul is an old one and has been referenced in many works , but mainly known in the form of playing Chess against the personified version of Death , which was made famous in Ingmar Bergman's film The Seventh Seal (1957). The last part of this trope is used in this comic. Here, the specific twist is that the victim can choose which game they want to play. Naturally, it is only fitting that Gary would challenge Death to D&D . The trope was later revisited as one of the tips in 1820: Security Advice . The problem is that Dungeons and Dragons isn't so much a game as it is a set of rules for describing stories. It requires the intervention of a Dungeon Master (or DM) to create a scenario that the players' characters must overcome. It's unclear exactly how the game between Gary and Death works, but given that D&D generally takes a long time to play due to the setup time and large amount of dice-rolling, and the fact that Gary seems to keep adding extra rulebooks (official or pseudo-official books that add new classes, items, spells, etc. for players to use), it's understandable why it would take longer than Death's boss would like. Part of the humor in this comic comes from the fact that Death's boss, who would presumably be an extraordinarily powerful entity, appears to be a completely ordinary man in an ordinary office, complete with bald patch and potted plant. Death's usage of the name "Jesus" in the final panel may be considered ironic, given that he's, well, Death. But it does make a different kind of sense when you consider Jesus a personal enemy of Death (Revelation 20:14). [Split screen down the diagonal. Upper left: A man with only hair around the back of his head is standing to the left of a desk with a hand on it, speaking on an office phone on a desk. There is a photo in a frame behind the phone. Bottom right: Death in a cloak, black hole to the left where the head should be, speaks on cell phone he is holding up in his skeleton hand.] Man: Death? Death: Speaking. [A frameless panel with a zoom out of the man on the phone, showing more of his office. Behind the desk, there is a potted plant, and above it, there is a window (or a white board). The reply over the phone is indicated to come from the phone with a zigzag line.] Man: This is the boss. Where are you? You haven't been up to the office in days! Death (over the phone): I've been held up. [Full panel with Death speaking on his cell phone. It is apparent that he is leaning back against something white behind him (presumably the backrest of his chair). The two replies on the phone are again indicated with zigzag lines.] Man (over the phone): What happened? Death: You know how when someone dies, they can challenge me to a game for their soul? Man (over the phone): Sure, standard procedure. [Death is revealed to be sitting on a chair to the right of a table leaning back against the chair's backrest (which could be seen in the first two images of Death as well). He is still speaking on his phone, and in the other hand he holds his long scythe down with the blade below the table. On the other side of the table is a man (revealed to be Gary Gygax in the title text). The man has curly hair that seems to turn into a ponytail, but as he is looking out of the panel a little to the left away from Death, it is hard to see the ponytail. He also has a full beard. Gary Gygax is leaning over his bag behind him, taking out a book while resting the other hand on the table. On the table are already two other books of the same type. Behind them are two figurines (one Cueball and one with a pointy hat), then two dice and some paper strewn about in front of Death.] Death: Well, we didn't count on this guy. I might be a while. Gary Gygax: I add the paladin to my party. Death: Oh, Jesus. He's getting out another rulebook.

Kilobyte

Kilobyte

https://www.xkcd.com/394

https://www.explainxkcd.com/wiki/index.php/394:_Kilobyte

There's been a lot of confusion over 1024 vs 1000, kbyte vs kbit, and the capitalization for each. Here, at last, is a single, definitive standard: [table of various kinds of kilobytes] SYMBOL NAME SIZE NOTES kB Kilobyte 1024 bytes OR 1000 bytes 1000 bytes during leap years, 1024 otherwise KB Kelly-Bootle standard unit 1012 bytes compromise between 1000 and 1024 bytes KiB Imaginary kilobyte 1024 √-1 bytes used in quantum computing kb Intel kilobyte 1023.937528 bytes calculated on Pentium F.P.U. Kb Drivemaker's kilobyte currently 908 bytes shrinks by 4 bytes each year for marketing reasons KBa Baker's kilobyte 1152 bytes 9 bits to the byte since you're such a good customer

This comic pokes fun at the confusion over the definition of a kilobyte. Historically, 1024 bytes was called a kilobyte for convenience purposes (same with megabyte and gigabyte); this usage was frowned upon by both the International Bureau of Weights and Measures and the Institute of Electrical and Electronics Engineers , but both let it slide as they had more important things to deal with. Later, hard drive manufacturers realized they could save money by selling hard drives marketed X amount of gigabytes and declare that they meant it as a literal 1,000,000 bytes (a 7% difference). Despite its iffy origins, the official definition now states that 1 kilobyte is 1000 bytes, however some continue to use the older meaning referring to 1024. The first row of the table is simply mocking this discrepancy. The second row is Randall's interpretation on how Stan Kelly-Bootle would approach this problem. Kelly-Bootle is known for writing The Computer Contradictionary , which satirizes the jargon and language of the computer industry. Kelly-Bootle was likely motivated to write this work after working for several years at IBM, a company infamous for its excessive use of acronyms in the work place. Averaging the two definitions together to get 1012 bytes is simply a humorous approach that Kelly-Bootle would likely have taken (" Should array indices start at 0 or 1? My compromise of 0.5 was rejected without, I thought, proper consideration. " — Stan Kelly-Bootle). The serendipitous fact that the initials of Kelly-Bootle's name are "KB," the same letters used to abbreviate the word "kilobyte," adds a layer of plausibility to the joke. This is the first of Randall's many humorous compromises . The imaginary kilobyte simply plays on the fact that complex analysis is required in quantum computing in relation to quantum mechanics. The imaginary number is represented as i and has a value of the square root of -1. This is a pun on the fact that KiB is used for the "binary kilobyte" (occasionally " kibibyte "), which is standardized at 1024 bytes. The Intel kilobyte mocks the Pentium floating point unit that, in 1994, became notorious for having a major flaw in its floating point division algorithm that gave slightly erroneous results. The smaller, drivemaker's kilobyte mocks a business model for handling higher prices that keeps prices constant but reduces quantity. The food industry has been notorious for decreasing quantity of food and keeping prices the same instead of increasing prices and keeping quantity the same. Randall is suggesting that if the computer industry tried to do this with hard drives, it could have humorous results such as smaller number of bytes in a kilobyte. In reality, hard drive capacity is specified in 10 3 byte (kB) units, while the content you put on it (programs, etc.) is specified in 2 10 (KiB) units. Formatting the drive, i.e. making it usable for storage, further decreases the available space. Thus a 250 GB drive might be reported to have a capacity of only 232 GB (really GiB) by the operating system. This discrepancy increases with increasing drive size. The trend humorously suggested in the comic, however, would make the drivemaker's kilobyte 1024 bytes in 1979, 1000 bytes in 1985, 852 bytes in 2022, and 0 bytes in 2235! The baker's kilobyte is a play on the baker's dozen , which is 13 instead of 12. A baker's byte with 9 bits to the byte would result in a total of 9216 bits in a 1024 byte kilobyte. Converting this into "normal" bytes (with 8 bits), we divide 9216 bits by 8 bits per byte to get 1152 8-bit bytes to the baker's kilobyte. In the title text, Randall mentions the definition kibibyte , which is defined more precisely. The binary prefix kibi means 1024, a portmanteau of the words kilo and binary. But he doesn't like the word because it sounds like the dog food Kibbles 'n Bits . There's been a lot of confusion over 1024 vs 1000, kbyte vs kbit, and the capitalization for each. Here, at last, is a single, definitive standard: [table of various kinds of kilobytes] SYMBOL NAME SIZE NOTES kB Kilobyte 1024 bytes OR 1000 bytes 1000 bytes during leap years, 1024 otherwise KB Kelly-Bootle standard unit 1012 bytes compromise between 1000 and 1024 bytes KiB Imaginary kilobyte 1024 √-1 bytes used in quantum computing kb Intel kilobyte 1023.937528 bytes calculated on Pentium F.P.U. Kb Drivemaker's kilobyte currently 908 bytes shrinks by 4 bytes each year for marketing reasons KBa Baker's kilobyte 1152 bytes 9 bits to the byte since you're such a good customer

Morning

Morning

https://www.xkcd.com/395

https://www.explainxkcd.com/wiki/index.php/395:_Morning

[Megan is standing to one side.] We've all seen The Matrix We've all joked about "What resolution is life" But it doesn't blunt the shock Of waking up one morning [Megan looks up from field and sees several colored pixels in the sky.] And seeing dead pixels in the sky.

This comic makes reference to the idea, as presented in the movie The Matrix , that reality is a computer simulation. In LCD screens , especially TFT LCD , a dead pixel is a pixel that does not work properly, usually set as black or as some other color. Megan realizes that the reality is a computer simulation when she sees dead pixels in the sky, indicating that what she sees is an LCD screen. In the last panel of the comic, there are two red and one green pixel that look exactly like actual dead pixels. The title text refers to usual techniques for fixing a dead pixel. One way is to apply pressure and release it, which isn't possible for Megan due to the distance of the sky. Another way is to make the area of the screen that the dead pixel is on change colors really quickly, which could happen if the day-night cycle was fast enough. [Megan is standing to one side.] We've all seen The Matrix We've all joked about "What resolution is life" But it doesn't blunt the shock Of waking up one morning [Megan looks up from field and sees several colored pixels in the sky.] And seeing dead pixels in the sky.

The Ring

The Ring

https://www.xkcd.com/396

https://www.explainxkcd.com/wiki/index.php/396:_The_Ring

[Ponytail is speaking to young Cueball sitting in front of a TV with a black background and a white ring.] Ponytail: You watched the tape!? Cueball: Yeah, sorry. Ponytail: Now you'll die in seven days! Cueball: It's worse than that. [TV is cut from the frame.] Ponytail: ...You didn't. Cueball: Yup. [Both are now in front of a computer, Ponytail leaning in.] Ponytail: Great, it's got 363,104 views already . Cueball: It was only fair. Cueball: They kept Rickrolling me!

The Ring is a horror movie released in 2002 based off of the Japanese movie Ringu . In it, there is a video tape that causes everyone who watches it to die after seven days. However, the viewer can prevent their death by making a copy of the tape and giving it to someone else. A young Cueball watches the tape and prevents his own death by "copying" the tape and uploading it to a video-sharing website, presumably YouTube . Cueball not only got one person to watch it, the requirement for escaping death, but 363,104 people, all of whom are most likely going to die in seven days. (For scale, the most-watched video at the time of the comic's publication had 78 million views.) Rickrolling is an Internet meme where someone is lured into clicking on a video link of Rick Astley singing " Never Gonna Give You Up ." When someone is rickrolled, they usually get very upset. Cueball states in the comic that he uploaded the tape to get revenge on everyone who rickrolled him, though it was obvious that he would likely kill many more people than those who rickrolled him (or those who've rickrolled anyone else). The title text refers to the file format used by the YouTube player. Historically, YouTube was famous for having extremely poor quality videos, because their Internet connections were slower and server storage space was expensive. So, all videos were transcoded into a very low quality FLV (flash video) format. The girl shown in the video tape — a major part of The Ring series — is named Samara. Posting the tape on YouTube would result in heavily compressed videos in the FLV format. This, presumably, would reduce the quality of Samara's apparition. The title text also implies that nobody deserves that, although rickrolling is (according to young Cueball) apparently punishable by death. [Ponytail is speaking to young Cueball sitting in front of a TV with a black background and a white ring.] Ponytail: You watched the tape!? Cueball: Yeah, sorry. Ponytail: Now you'll die in seven days! Cueball: It's worse than that. [TV is cut from the frame.] Ponytail: ...You didn't. Cueball: Yup. [Both are now in front of a computer, Ponytail leaning in.] Ponytail: Great, it's got 363,104 views already . Cueball: It was only fair. Cueball: They kept Rickrolling me!

Unscientific

Unscientific

https://www.xkcd.com/397

https://www.explainxkcd.com/wiki/index.php/397:_Unscientific

[Cueball and Megan are sitting on a coach, watching Mythbusters.] TV: Can a ninja catch an arrow? On this episode, we'll find out! Cueball: Mmm, science. Megan: Hey, Mythbusters is entertaining, but it's not science. Zombie Feynman: BRAAAAAIIINNS ... Cueball: Zombie Feynman! Zombie Feynman: You got a problem with Mythbusters? Megan: They fail at basic rigor! Zombie Feynman: "Ideas are tested by experiment." That is the core of science. Everything else is bookkeeping. Zombie Feynman: By teaching people to hold their beliefs up to experiment, Mythbusters is doing more to drag humanity out of the unscientific darkness than a thousand lessons in rigor. Show them some love. Zombie Feynman: Anyway, back to zombie stuff. I hunger for BRAAAAAIIINNS! Cueball: Uh, try the physics lab next door. Zombie Feynman: I said brains . All they've got are string theorists.

In the first and second frames, Megan can be seen accusing MythBusters of not actually "doing science" because of its lack of rigor - a debate beyond the scope of this Wiki. The zombie of deceased physicist, Richard Feynman , comes to explain to Megan that she has failed to recognize the purpose of MythBusters . He explains that MythBusters' value is getting people to accept and understand the importance of experimentation in the scientific method, and that more complex lessons (such as on rigor) would be wasted on people who don't understand those basics. In the last frame, Cueball attempts to save himself and Megan from zombie Feynman by implying that physicists, being extremely intelligent, would have more desirable brains. Also, in a science lab, the number of brains available would be higher than just two. Feynman's closing remark implies that string theorists have no brains; the joke being that string theorists are presumably less intelligent than Cueball and Megan, who were merely watching television prior to being attacked, and probably also a pun on branes . For another instance of Randall knocking string theorists, see 171: String Theory . This notion fits appropriately with Feynman's description of the core of science. Moreover, Feynman's own career involved applying physics to real world applications (such as for the Manhattan Project), whereas the work of string theorists is theoretical and untested. The title text starts by rebounding against the complaint of validity as science by purportedly tackling a really big scientific inquiry. Then he veers away into two far more esoteric proposed fields of study, of which at least one is not even determinable by the scientific method, probably both. The Mythbusters episode being watched is likely Episode 109 – "Ninjas 2" , which was the second episode in which the Mythbusters attempted to catch an arrow mid-flight. The voice from the television is likely that of Robert Lee , who provided the narration for Mythbusters . It should also be noted that the ninja mentioned in this is the inaccurate pop culture iteration not the historical Shinobi no Mono. for more accurate info on the Shinobi search "Antony Cummins" . Zombies are a recurring theme in xkcd, particularly zombie scientists, which has also occurred twice after this comic with Paul Erdős in 599: Apocalypse and Marie Curie in 896: Marie Curie . [Cueball and Megan are sitting on a coach, watching Mythbusters.] TV: Can a ninja catch an arrow? On this episode, we'll find out! Cueball: Mmm, science. Megan: Hey, Mythbusters is entertaining, but it's not science. Zombie Feynman: BRAAAAAIIINNS ... Cueball: Zombie Feynman! Zombie Feynman: You got a problem with Mythbusters? Megan: They fail at basic rigor! Zombie Feynman: "Ideas are tested by experiment." That is the core of science. Everything else is bookkeeping. Zombie Feynman: By teaching people to hold their beliefs up to experiment, Mythbusters is doing more to drag humanity out of the unscientific darkness than a thousand lessons in rigor. Show them some love. Zombie Feynman: Anyway, back to zombie stuff. I hunger for BRAAAAAIIINNS! Cueball: Uh, try the physics lab next door. Zombie Feynman: I said brains . All they've got are string theorists.

Tap That Ass

Tap That Ass

https://www.xkcd.com/398

https://www.explainxkcd.com/wiki/index.php/398:_Tap_That_Ass

[Cueball in a hallway looking in on a board meeting.] Cueball: I'd tap that ass to be the new committee chair. [Cueball wearing headphones with a briefcase and a laptop. Another man on a telephone.] Cueball: I'd tap that ass without a warrant. [Cueball with his hand on his chin, looking at a tree.] Cueball: I'd tap that ass and extract delicious maple syrup. [Cueball standing in a blank frame.] Cueball: I'd have sex with that tree.

In this comic, Cueball either accidentally or purposefully exploits the double meanings of "tap." The phrase "tap that ass" is a colloquialism for "to have intercourse with that person" and is most likely how the reader expects the phrase to be used. However, throughout the comic, Cueball uses the phrase ambiguously. In the first panel, it is possible that Cueball is using "tap that ass" sexually. However, it is more likely that he is using "tap" to mean "pick" or "choose," in which case he would be the one choosing the next committee chair. "That ass" refers to one of the individuals in the meeting room to be picked for the position. In the second panel, "tap" is referring to wiretapping. The Cueball character with the headphones on has just unplugged his headphone. This suggests that he and his colleague at the phone were just done with the wiretapping. In this scenario, it is strange that the colleague is still on the phone instead of hanging up. However, it would be much stranger to wiretap someone in plain eyesight, unless that person is blind. "Ass" likely refers to the person they have just wiretapped. Cueball says he'd tap that ass "without a warrant," suggesting that they had one in this situation. In the third panel, "tap" is referring to extracting sap from trees. A sexual connotation would make no sense in this context. "That ass" refers to the maple tree. The final panel reveals that Cueball was purposefully implying the sexual meaning of "tap that ass" all along, even though he framed it in a non-sexual context. He reaffirms his previous statement from the third panel by turning toward the direction of the third panel (thus implicitly breaking the fourth wall) and asserting "I'd have sex with that tree." "That tree" refers to the tree from the previous panel. Alternatively, Cueball may have finally realized that he indeed wanted to have sex, but instead of using the euphemism "tap that ass," he says it literally. The title text features a request from Cueball from the last panel to Cueball from the third panel. He asks Cueball not to plug up the hole left behind from tapping the tree, so he can have sex with it. [Cueball in a hallway looking in on a board meeting.] Cueball: I'd tap that ass to be the new committee chair. [Cueball wearing headphones with a briefcase and a laptop. Another man on a telephone.] Cueball: I'd tap that ass without a warrant. [Cueball with his hand on his chin, looking at a tree.] Cueball: I'd tap that ass and extract delicious maple syrup. [Cueball standing in a blank frame.] Cueball: I'd have sex with that tree.

Travelling Salesman Problem

Travelling Salesman Problem

https://www.xkcd.com/399

https://www.explainxkcd.com/wiki/index.php/399:_Travelling_Salesman_Problem

[There is a linked black web, with a path in red; it appears to be a map of the United States.] Brute-force solution:O(n!) [The web continues in this one. A man with a brown hat and a case is drawing it.] Dynamic programming algorithms: O(n 2 2 n ) [Another man, with a brown hat too, is at a computer, looking back over the chair.] Selling on eBay: O(1) eBay salesman: Still working on your route? Drawing salesman: Shut the hell up.

The travelling salesman problem is a classic problem in computer science. An intuitive way of stating this problem is that given a list of cities and the distances between pairs of them, the task is to find the shortest possible route that visits each city exactly once and then returns to the origin city. A naïve solution solves the problem in O(n!) time (where n is the size of the list), simply by checking all possible routes, and selecting the shortest one. However, this approach will take a long time as the number of possible routes increases exponentially as more nodes are included. A more efficient dynamic programming approach yields a solution in O(n 2 2 n ) time. These times are given using Big O notation , which is commonly used in computer science to show the efficiency or complexity of a solution or algorithm. The joke is that the salesman selling online (say on eBay , Amazon Marketplace , or other virtual marketplace) does not have to worry about this problem, since he does not need to travel (which makes the time to find the best solution O(1)), to which the travelling salesman angrily responds, "Shut the hell up." The title text wonders about the time complexity of the cutting-plane method , which is sometimes used to solve optimization problems. The last sentence suggests the downside for Randall of drawing comics about computer science; he sometimes encounters problems to which he cannot find the answer, whereas authors of simpler comics such as Garfield do not have this problem. This is also likely a reference to 78: Garfield , which parodies Garfield's simplicity. The map almost certainly depicts the United States, with the locations highlighted suspected to be (from left to right): Seattle, San Francisco, Los Angeles, Phoenix, Denver, Minneapolis, Dallas, San Antonio, Houston, Chicago (cut off), Detroit, Atlanta, Miami, Washington D.C., Philadelphia, New York, and Boston. This is so far the only comic featuring the Brown Hat character. Also see earlier strip 287: NP-Complete . [There is a linked black web, with a path in red; it appears to be a map of the United States.] Brute-force solution:O(n!) [The web continues in this one. A man with a brown hat and a case is drawing it.] Dynamic programming algorithms: O(n 2 2 n ) [Another man, with a brown hat too, is at a computer, looking back over the chair.] Selling on eBay: O(1) eBay salesman: Still working on your route? Drawing salesman: Shut the hell up.

Important Life Lesson

Important Life Lesson

https://www.xkcd.com/400

https://www.explainxkcd.com/wiki/index.php/400:_Important_Life_Lesson

Important life lesson: If there's any possibility of sex, do not leave your music library on "shuffle all." [Megan lies down in a bed, while Cueball is beneath the bed sheets with his head between her legs. On the other side of the room, a computer is turned on and playing music.] Megan: *GASP* MMMMM- Computer: GO GO POWER RANGERS!

It's common to have music playing in the background when two individuals decide to engage in sexual behavior. However, some people have a lot of silly or funny songs in the same music library as their more dramatic or romantic song choices. If the library is left to randomly choose songs from the whole library, those more whimsical songs could easily come up, suddenly ending the intimate mood. Cueball is performing cunnilingus on Megan, while a particularly goofy song, the Power Rangers Theme , plays in the background. The title text alludes to an even sillier song, the Monty Python song Lumberjack , which is about a transvestite lumberjack. Important life lesson: If there's any possibility of sex, do not leave your music library on "shuffle all." [Megan lies down in a bed, while Cueball is beneath the bed sheets with his head between her legs. On the other side of the room, a computer is turned on and playing music.] Megan: *GASP* MMMMM- Computer: GO GO POWER RANGERS!