Code Quality 2

Explanation:
This comic is the second in the Code Quality series:
It is because it is so clearly a continuation of the first that it is clear that it is Cueball who answers from off-panel.
As in the first we again see Ponytail being introduced to the source code Cueball has written, and where he is warning her that he is self-taught so his code probably won't be written the way she is used to. In the first comic she continues to describe poetically the total mess of a code she encounters, using references to a child building houses, recipes created by corporate lawyers or the transcript of a couple arguing at IKEA, as well as using emojis in the code (title text).
In this comic she continues this trend in four more abusive comments, after starting this sequel with a short remark on how she hates reading Cueball’s code. Cueball is not even shown in this comic, only replying twice off-panel, but as the title makes it clear this is a sequel there can be no doubt that it is Cueball. With the four remarks here as well as a fifth in the title text, she has now managed to make no fewer than nine derogatory remarks on Cueball's programming skills.
In the second panel Ponytail makes a reference to "OCR" ( Optical Character Recognition ), a technique for recognizing text in a picture using software. In this case she is referring to a picture of a Scrabble game, which is a popular word-making game in which players have a pseudo-randomized set of letters and must arrange them on a grid to form interlocking words. OCR software is notoriously imperfect at the time of writing, and the criss-crossing semi-random words on a Scrabble board fed through an OCR program would likely produce dubious results, certainly not fit for current code standards.
Ponytail observes that Cueball’s code includes the JavaScript reserved words more often than a typical Scrabble board would, a concession that the code looks at least vaguely code-like. Reserved words such as ‘function’, ‘if’ and ‘return’ are fundamental building blocks of code, and most code uses them often. (They are called “reserved” because those words are reserved for their actual meanings such as defining a function — programmers may not create variables with those names.) As for why “triple points” translates to a prevalence of those words, Scrabble's point system is based on the value of individual letters, combined with certain modifier squares on the game board which can boost points. "Triple points" is the highest class of modifier available in the game (though it can be for triple points on a specific letter, or the entire word) and is highly-sought-after by players.
The third panel continues Ponytail's rant, this time referencing naval weather forecasts, avian interference and indentation. A weather forecast is a complex, multidimensional array of data used in predicting or assessing the atmospheric conditions of a geographical area over a set time. Naval weather forecasts (archive) use an extremely condensed code to send their information, rendering them unintelligible to an untrained reader. Transcribing it would be further complicated by a woodpecker (a bird noted for its rapid successive pecking motions) "hammering" (pecking) the Shift key on the keyboard, which would result in many letters being randomly capitalized. Indentation is the practice of shifting a section of text further from the starting margin, which in coding is typically used to organize functions and statements, but if done "randomly" would only serve to scramble the code hierarchy.
The fourth panel references famous poet E. E. Cummings and user name suggestions. Edward Estlin Cummings was a poet who used capitalization, punctuation, and line breaks in unconventional ways. Websites that offer membership often also require that users create a pseudonym (known as a "username") for use in tracking/authenticating their actions on the site, as well as identifying them to the site's community. Many of these sites also require usernames be unique. On popular sites, many common words, phrases and names have already been reserved by users, so when signing up for them many people run into situations where the name they want has already been taken. On many sites where this happens, the site may suggest alternate usernames, usually based on the one that was entered to begin with. For example, if the username "Hedgeclipper" is already reserved, the site may recommend "Hedgeclipper1234" or "H3dg3clipp3r" instead, depending on the algorithm behind the suggestions. In other cases, websites requiring users to enter personal information such as their name may suggest a username based on their name with a string of digits after it, such as "Joshua1128". An E. E. Cummings poem written entirely out of these semi-random suggestions would make the resulting poem even more "unusual" than his work is already considered.
The last panel's simile involves Markov chaining , chat-bots (presumably), bus schedules and potential gross vehicular negligence. Applied Markov chaining is a process used in many computer algorithms that try to simulate real-world concepts such as speech simulation and decisions-making. Its inherent randomness also makes it a candidate for unpredictable things such as stock market analysis and speech recognition. Bus schedules are often complicated and full of notation , and are notorious for confusing people who are not used to reading them. Chat-bots using applied Markov chains to recognize and respond to speech/text rely on the input being clear and well-organized in plain language. "Feeding" bus schedules to such a bot would likely result in the returns being complete gibberish and unreadable, especially if the reason that the buses crash constantly is because the bus schedules are too incoherent for the bus drivers to understand. The issue is further complicated when Ponytail suggests that the schedules are from a city where "the buses crash constantly", which would be horrifying if it happened so regularly that the schedules actually took crashes into account. However, the reason for the crashes is not stated, and it is not clear whether the passengers are in any danger. The buses might be safe if the problem is pedestrian suicides. Even more horrifying would be the further unpredictability of the output of the chat-bot from such unpredictable input.
Cueball finally comments that "… it runs fine for now" which indicates he knows the code has problems but is reluctant to fix them because it's more-or-less serving its function. Ponytail quips back that "So does a burning bus", which is technically true, but the "for now" part implies that disaster and injury could result at any moment, as would likely happen on a burning bus.
In the title text, Ponytail makes a final remark. A formal grammar is a way of describing the structure of text such that computers can recognize or generate such text. A raw database dump is an export of the data from a database for the purposes of transferring it to another database or importing it into a program, viewed “raw” without processing to make it easy for humans to read. QuickBooks is an accounting software package. The company collapsing in an accounting scandal implies their accounting database would be a mess even in a human-readable format.
[Zoom in on Ponytail sitting in front of a computer screen typing. Cueball speaks only off-panel, but since this is a direct continuation of comic 1513: Code Quality where Cueball is shown, there can be no doubt it is him.] Ponytail: Ugh, I hate reading your code. Cueball (off-panel): I know, I know.
[Zoom out of Ponytail in an office chair in front of the computer on a desk.] Ponytail: It's like you ran OCR on a photo of a Scrabble board from a game where Javascript reserved words counted for triple points.
[Zoom in on Ponytails head.] Ponytail: It looks like someone transcribed a naval weather forecast while woodpeckers hammered their shift keys, then randomly indented it.
[Zoom out back to the setting of the second panel.] Ponytail: It's like an E E Cummings poem written using only the usernames a website suggests when the one you want is taken.
[Zoom in to Ponytails head and the screen in a wider panel. Finally Cueball again answers off-panel.] Ponytail: This looks like the output of a Markov bot that's been fed bus timetables from a city where the buses crash constantly. Cueball (off-panel): Whatever, it runs fine for now. Ponytail: So does a burning bus.


AI Research

Explanation:
This is another one of Randall's Tips , this time an AI Tip.
Developing artificial intelligence (AI) has been a challenge for a long time. Even to develop one with the intelligence of a six-year-old child would be a great milestone, and presumably a stepping stone on the path to making one with the intelligence of an adult human.
In this comic, Randall / Cueball jokingly suggests that in order to accomplish this goal, one can give him an AI that's already as smart as an adult, and let him teach it childish and silly things. He is shown teaching it dumb jokes, much like the ones a sassy six-year-old would make, as the first "fart" joke where art ificial is changed to fart ificial.
The humor in the comic is that Randall is essentially accomplishing the present goal of a six-year-old-equivalent AI by starting with the final goal, which is a full human intelligence, and making it dumber, just by teaching it poor humor. This is not unlike the old joke, "The easiest way to make a small fortune on Wall Street [or similar] is to start with a large one."
The specific situation may also be a reference to Tay , a Microsoft chatbot that was taught to troll within hours of its exposure to the public.
" Updog " refers to a light-hearted practical joke in which the perpetrator casually uses the neologism 'updog' in a sentence ("Hey, I'm going to get some updog, you want any?"). The unsuspecting listener is expected to be curious about the meaning of the neologism and ask the perpetrator its meaning, specifically in the format "What's 'updog'?", inadvertently invoking the highly casual greeting of "What's up, dawg?". The perpetrator then draws attention to this by replying along the lines of "Not much, you?", causing the target to realize the foolish thing they just said. Other neologisms used in the context of this joke include 'updoc', 'snoo', and 'samatta' (" What's up, doc? ", "What's new?", and "What's the matter?", respectively). Updog is mainly an American joke not particularly well known in other English-speaking countries.
In the title text there is a joke on lambda calculus , where lam bda is changed to SHAM bda. Lambda calculus is an area of mathematical logic and theoretical computer science. It is a formal language which can express computation and evaluation. It is Turing Complete, which means it can do any computation which can be executed by a computer. However, it is very simple, consisting only of two primitive notions: abstraction , which is forming a unary function (a function that takes one argument) and application which is applying a function to an input value. For example, a function which squares a given number can be written λx.x². Here the λ indicates an abstraction (hence the name lambda calculus ), the x is the input value and the output is x² . As an example of application, if we apply this function to 5, we get (λx.x²)(5) = 5² = 25. The title text makes fun of this by inserting the word "Sham" into the phrase, a word used to describe a trick or con; essentially, it denies that such calculus is useful or valid.
The title text finishes with amirite , short for am I right? which is often used to finish sentences on web forums, to prevent anyone saying you are wrong. Not very mature to use in a serious discussion, so very fit to use for a AI that tries to emulate the intelligence of a six-year-old.
[Cueball (representing Randall, or at least the person who wrote the caption) is standing in front of a computer console displaying AI, talking to it. The computers reply is indicated to come from the console with a zigzag line, rather than the straight lines for Cueball.] Cueball: Then you say "More like fart ificial intelligence!" Computer: Understood. Cueball: Great! Now let me teach you about "updog".
AI tip: To develop a computer with the intelligence of a six-year-old child, start with one as smart as an adult and let me teach it stuff.


Intervocalic Fortition

Explanation:
The linguistic processes of lenition ("weakening") and fortition ("strengthening") refer to a sound becoming, respectively, either more or less vowel-like. Intervocalic means "between two vowels." An unvoiced consonant like f in between two vowels (which are almost always voiced) is more noticeable and takes more effort to pronounce than the voiced version v of the same sound in that position, so a change from v to f in this context would be an example of fortition. As a rule, however, lenition is much more common, and in fact one of the most common regular changes observed across languages is the kind of lenition that is the precise opposite of Cueball's prank: An unvoiced consonant between two vowels comes to be spoken, over time, as a voiced consonant, such as the middle consonant in the word "butter" that in American English is now pronounced as a brief alveolar tap [ɾ] rather than [t]. Observing a pattern of fortition rather than lenition in that position (especially for just one particular consonant) would be a very puzzling phenomenon to future linguists.
Examples for the suggested change are:
In some languages, like German and Dutch, V is often pronounced like F. But it is not always the case.
The title text refers to the fact that English phonotactics tend to discourage final or unstressed /ɛ/ . Exceptions tend to be monosyllabic interjections, such as:
The word 'meh' is an interjection used to express boredom or indifference. The suggestion that it was originated by the writers of the animated TV show, The Simpsons , is incorrect . However, its use did surge in popularity following its use in various episodes of the show, beginning with the 1994 episode "Sideshow Bob Roberts".
This is the second time in 2016 that Randall tries to spread linguistic misinformation, the first being 1677: Contrails , but since both are in the My Hobby series it is not so strange.
[Cueball holding his hands in front of his mouth is whispering into a Cueball-like person's ear. The second Cueball turns his head towards the first Cueball.] Cueball: Psst–teach your kids to pronounce V's in the middle of words as F's, but don't write down why you're doing it. Cueball: Pass it on.
[Caption below the panel:] My hobby: Playing pranks on future linguists


Theft Quadrants

Explanation:
This is an Eisenhower box comparing how difficult it is to steal a specified object with the severity of the theft.
It is very hard to steal nuclear launch codes . They are protected by many layers of federal security. That's a good thing, too, since if they were stolen, they could be used to start a nuclear war , which would cause untold death and destruction.
It is also hard to steal the Crown Jewels , since they are protected by a complex security system. But if they were stolen, it wouldn't be so bad for most people; the only direct loss would be to its owners, the British royal family, who are well-insured for thefts and only use the Crown Jewels as a display piece for museumgoers. It would also be a loss to the public as a cultural and historical artifact, but would have little practical effect on the world.
It wouldn't be too hard to steal the Wienermobile [ citation needed ] (a car shaped like a hot-dog, advertising the Oscar Mayer brand). There are several versions of this car, and it would not be more difficult to steal than any other car, although harder to hide. Randall seems to consider that such a stolen vehicle would not be too bad, although he has previously referred to a stolen Wienermobile in 935: Missed Connections , which is driven recklessly, almost hitting someone. But it is not bad enough to consider it a big problem in a context when it is compared with stolen nuclear launch codes.
It also wouldn't be hard (or at least, not as hard as stealing nuclear launch codes or the Crown Jewels) to steal the tinyurl.com domain name, but the consequences of that could be significant and is thus listed under very bad. The joke is of course that this is listed as just as bad as the risk of a nuclear war, and of course it is not as significant, but it could swiftly result in damage to a lot of important computers, and ruin references in journals etc.
TinyURL offers a URL shortening service. They provide short URLs that redirect to long ones. This is useful if you want to write down a very long URL as it saves typing and is more accurate. Other companies, including bit.ly , Google (ultimately fully discontinued March 30, 2019), and Twitter offer a similar service. TinyURL was, for a while, the most popular of these URL shortening services. If their domain name were stolen, all the redirects from short URLs could be changed to forward traffic to sites hosting, for example, malware. This would have significant effects on a large number of people, because TinyURL is used in many places both online and (as the title text notes) even sometimes offline.
In the title text Randall implies that stealing the tinyurl.com domain could happen when it next expires. A whois search as of February 2021 finds that the tinyurl.com domain is next due for renewal in January 2029. However, rule changes made by ICANN (the organization in charge of domain name registrations) now make it effectively impossible to steal a domain name because the owner allowed its registration to lapse. Current rules for .com registrations now allow for the original owner to renew their domain name after it expires during a 0-45 day auto-renew grace period. The exact length of this grace period depends on what company the domain is registered with. All registrars are then required to give a 30 day redemption grace period during which the domain may be renewed with penalty. As a result, tinyurl.com would have a 30-75 day period after expiration during which the domain is not available for registration by a third party. ICANN rules state that DNS resolution must be stopped during the redemption grace period, which means that there will be a 30 day period during which tinyurl.com will no longer work but the company will have the ability to quickly restore ownership of their domain. It is very unlikely that any company that is still in business would not notice that their domain name has expired before the end of the 30 day redemption grace period.
Another way to steal a domain name would be through domain name hijacking . There have been some high profile cases of domain name hijacking, with one of the more notable domains being nike.com in 2000 . However, whether or not this is a risk for any particular domain name is difficult to estimate. Additional security mechanisms such as domain name locking and private registrations have been introduced to mitigate the threat of domain name hijacking. Further, domain name hijacking relies on situation-specific attacks such as hacking email accounts, spoofing emails, and social engineering attacks against either the company who owns the domain name or the company who registers the domain name. For security-conscious companies, such attacks can be impossible, or at least an attacker's success may require security failures in more than one area. A summary of domain hijacking examples including an analysis of how they succeeded and what steps could have prevented them can be found here . In short though, there is no way to say for sure how vulnerable any particular domain name might be to hijacking.
[A chart with an Eisenhower box, consisting of four labelled squares. To the left the rows are labelled hard and easy and two lines goes to from these labels to a description of what the labels refer to saying "how hard thing would be to steal". On the bottom the rows are labelled not that bad and very bad and two lines goes to from these labels to a description of what the labels refer to saying "how bad it would be if someone stole it". The top left box is labelled "the Crown Jewels". The top right box is labelled "the nuclear launch codes". The bottom left box is labelled "the Oscar Mayer Wienermobile. The bottom right box is labelled "the tinyurl.com domain name".]


Local News

Explanation:
Typical news broadcasts are divided into local, national, and global news segments. The broadcast in this comic presented by Blondie , the news anchor , has been broken into real local, (about city council election) and what the newscaster calls "nonlocal". Rather than focusing on national or global news, the nonlocal segment deals with news of a nonlocality nature; more likely dealing with causal nonlocality.
A " tachyon " is a theoretical or thought-experiment particle which travels faster than the speed of light . It has many strange properties, including being able to go back in time. This is how the newscaster is able to send a beam back in time to kill her past self. The comic does not explain the paradox of how someone who died in the past could still be alive in the present/future, nor any of the many other paradoxes that arise when time travel is involved, a recurring theme in xkcd.
The title text asks if there could ever be a greater physics term than tachyonic antitelephone , a theoretical device which would allow messages to be sent to the past. The text then continues to answer the question via a message from the future (presumably sent by antitelephone). The answer is No - there will never be a greater physics term.
[Blondie as a news anchor is sitting behind a table with her arms resting on the tabletop.] Blondie: In local news, city council elections were held today. Blondie: In nonlocal news, I killed my past self with a tachyon beam.


New Bug

Explanation:
Cueball asks if an off-panel character can look at his bug report. The person asks if it's a "normal one," and not a "horrifying" one which proves that the entire project is "broken beyond repair and should be burned to the ground." This implies that there have been reports of the "horrifying" variety in the past.
Cueball promises that it is a normal one but it turns out that the server crashes when a user's password is a resolvable URL, which implies that the server is in some way attempting to resolve passwords as if they were URLs. A resolvable URL is one that is syntactically correct and refers to a find-able and accessible resource on the internet (i.e. does not return a 404 error or equivalent when resolved). Therefore a resolvable URL is a fully qualified domain name or a valid IP address that points to a valid server, and it can optionally specify a resource that exists on that server. Normally there is no reason for a system to treat a password as if it were a URL — and testing if a password is a resolvable URL would be a horrible thing to do as it would involve sending the password over the internet in a (at the time the comic was written) most likely completely unencrypted format.
Also, Cueball specifically states that the server is crashing, rather than his application. While this could be an example of misused terminology on the part of Cueball or Randall, given Cueball's history (for example causing the most basic console commands to fail in 1084: Server Problem or other tech issues as seen in 1586: Keyboard Problems ) his choice of terms is probably accurate. In the context of web services the server refers to either the computer itself or the program that responds to web requests and executes the user's (i.e. Cueball's) application. Cueball would be in charge of building the application. The importance of this distinction is that a typical system has safe guards in place at many levels to prevent a misbehaving application from crashing anything other than itself. So for his application to crash the server (either the computer itself or the server software hosting his application) would require his application to be operating in a way far outside of the normal, which has been the case for Cueball in previous comics. Alternatively, the project might include its own server software without the safeguards. In either case it is clear that Cueball's issue is far from normal, for which reason the off-panel person gives up and decides that burning the project to the ground is the only solution, telling Cueball I'll get the lighter fluid .
In the title text, another two issues with Cueball's program are mentioned, together with a possible solution that would fix all three problems at once. The second problem is a unicode-handling bug in the URL request library, and the third is that the passwords are stored unsalted. The proposed solution is to salt the passwords with emoji (unicode, multi-byte characters), which is claimed to solve all three issues at once. Salting passwords means that random characters are added to the password before it is cryptographically-secured and stored in the database. Salting increases security in the event that the database is compromised by ensuring that users with the same password will not have the same password hash. This makes some attacks that can be used to crack hash databases, such as rainbow tables , effectively impossible. Salting passwords with emoji can potentially "fix" these bugs in different ways. First, emoji and other unicode characters are not valid characters in URLs. As a result the salted-passwords will no longer be resolvable URLs. This will presumably circumvent (but not actually fix) the bug that causes the server to crash. In addition, the passwords will now be salted, increasing security. There is no obvious way that this would actually fix a unicode-handling bug in the URL request library. Given Cueball's general approach to problems like this, the best explanation is probably that he hasn't "fixed" the bug but rather that it is no longer a bug because he is relying on its behavior to help fix these other issues, i.e. the classic it's not a bug, it's a feature .
The title text shows that his general approach to problems is not to actually fix bugs but to work around them and even rely on them for other behavior. This approach to software development makes for terrible code, which is likely how Cueball got into this trouble in the first place. Therefore the title text shows that he still has yet to learn from his mistakes, further supporting the suggestion to just burn the whole thing down.
In the title text of the first, using emoji in variable names is mentioned. Emoji has since then become a recurrent theme on xkcd.
In 1349: Shouldn't Be Hard , Cueball is also programming and finding it very difficult, although he thinks it should be easy. An off-panel person suggests burning the computer down with a blowtorch, much like the off-panel person in this one suggests burning the whole project (including the computer) to the ground with lighter fluid. In the next comic, with multiple storylines 1350: Lorenz , one story line results in a computer being burned with a blow torch .
Interestingly, the 2021 vulnerability Log4Shell could be triggered when a specially crafted URL was logged with the Log4j framework. This could lead to a crash (as in the comic) or the computer being taken over by the attacker.  However, the contents of a password field should never be logged, so this still would indicate a major problem with the design of Cueball's project.
[Cueball sits at his desk in front of his computer leaning back and turning away from it to speak to a person off-panel.] Cueball: Can you take a look at the bug I just opened? Off-panel voice: Uh oh.
[Zoom out and pan to show only Cueball sitting on his chair facing away from the computer, which is now off-panel. The person speaking to him is still of panel even though this panel is much broader.] Off-panel voice: Is this a normal bug, or one of those horrifying ones that prove your whole project is broken beyond repair and should be burned to the ground?
[Zoom in on Cueball's head and upper torso.] Cueball: It's a normal one this time, I promise. Off-panel voice: OK, what's the bug?
[Back to a view similar to the first panel where Cueball has turned towards the computer and points at the screen with one hand.] Cueball: The server crashes if a user's password is a resolvable URL. Off-panel voice: I'll get the lighter fluid.


Speed and Danger

Explanation:
In this scatter plot Randall plots the speed of several vehicles (including people on foot for "normal sports") and how disastrous a crash would be. The punchline is that space rockets travel so dangerously fast, and crashes are so utterly catastrophic, that it pushes literally every other kind of crash to the "slow and safe" corner by comparison. (A similar punchline was used in the title text of 388: Fuck Grapefruit .)
With the plot Randall makes the observation that the danger of a crash is greatly influenced by its speed and highlights the concept of relativity between what we perceive as "fast," normal sports and two different types of racing cars, vs. a much faster vehicle, a rocket during launch. A rocket may appear to ascend slowly (and of course it begins its ascent slowly), but on the way to orbit it ends up moving very fast. But before it reaches the more extreme speed regime it will be far away from the ground (and the casual observer), where there is nothing to compare this speed to as opposed to a race car speeding by a spectator during a race.
Apart from the high speed, there is also the altitude to take into account for a rocket launch, and the vast amount of fuel needed to get into orbit, and any sort of catastrophic failure is almost certainly fatal ( Apollo 13 notwithstanding).
Racing cars are often involved in crashes, but at that speed it is possible to construct them so even serious crashes may not be fatal. Although rockets are also made as safe as possible, it is a completely different regime of speed and danger , and the risk of something going wrong during a take off is much higher, and it is impossible to prevent a lethal disaster if the launch fails during the ascent. This results in a much higher mortality rate for each crashed rocket (probably 100%) vs. crashed sports/race cars.
Rocket launches are compared to "normal sports " (presumably meaning people running approximately 25 km/h, and possibly also polo horses galloping approximately 40 km/h), NASCAR (which reaches speed of 320 km/h), and Formula One (F1), where the fastest race cars go 380 km/h. Although peak speed for an F1 car is higher than NASCAR, the average lap speed is much lower as F1 tracks have slow corners while NASCAR ovals can be negotiated with much less speed variation. It is also arguable whether F1 is more dangerous than NASCAR - there have been fewer fatalities in F1 this millennium, though fewer cars compete and races are of shorter duration. The 2016 Formula one season had 21 races, with each race lasting 1.5~3 hours. The NASCAR season had 36 races, with each race lasting 3~5 hours.
A rocket launched to reach the ISS needs to match the speed of the space station which moves at 27,600 km/h. A rocket that needs to escape from Earth needs to reach 40,270 km/h, but so far no humans have escaped. However, the astronauts going to the Moon came close, with Apollo 10 setting the speed record for manned flights with 39,896 km/h. (It was only about 0.4% faster than the next 7 missions that, in contrast to Apollo 10, were supposed to land on the Moon). The lowest of the rocket speeds mentioned above  is still more than 70 times as fast as the highest speed for race cars.
The title text serves to emphasize the point further, as an astronaut (used to the several G's of acceleration during takeoff and overall much higher speeds) would likely find a NASCAR car moving at ~300 km/h paltry compared to what they're acclimated to and has supposedly aggravated NASCAR drivers by making a point of saying so. And thus this is used to explain why there are no passenger seats in NASCAR cars, to prevent astronauts from joining the drivers for a nice, slow ride.
Of the many charts in xkcd this one is notable for containing the fewest sample points of any scatter plots in xkcd.
[A two-axis diagram with two double headed arrows centered in the middle of the panel. Each arrow is labeled. There are four large dots in the diagram, three close together in the top left corner and one in the bottom right corner. Each dot is labeled.]
[Y axis:] Top: Crashes are safe Bottom: Crashes are dangerous
[X axis:] Left: Slow Right: Fast
[Dots from top left to bottom right:] Normal sports NASCAR Formula One Rocket launches


Home Itch Remedies

Explanation:
Bug bites , such as mosquito bites, are itchy. Home remedies are often ineffective, and in some cases very complicated - think of the number of suggestions on how to cure hiccups. In this case Cueball 's suggestion starts out plausible but rapidly gets increasingly and insanely complicated, involving finding rare French orchids. Megan is not actually interested in trying out a complex home remedy, she really just wants sympathy.
The suggested remedy is a mix of many popular home remedies such as:
Megan's answer is a sarcastic comment stating that her own family home remedy is to keep scratching until the skin falls off -- which is a natural tendency, although not until the skin literally falls off; hence it is not really a home remedy, just a natural reaction.
The title text refers to chiggers or Trombicula alfreddugesi as the worst source for itches; in fact only in the larval stages are these mites parasitic. Chigger can also refer to the chigoe flea or "jigger", Tunga penetrans , a parasitic flea which also causes bad itching, but Randall explicitly mentions the mite Trombicula alfreddugesi . A move to a more northerly region of the world like Iceland might seem to be a perfect cure, because those parasites are only found in warmer southern regions (similarly, since mosquitoes lay their eggs in water, moving to a dry place with no water usable by mosquitoes would be a "cure" for mosquito bites). Unusually, Iceland does not support native mosquitoes, despite similarities to other northern regions which do. One might fallaciously assume it does not support parasites in general — but it does support parasitic insects in other genera, and it has other species of mites.  Thus, "move to Iceland" is a weird home remedy that will work if the person wants to prevent chiggers, however it won't work if the person wants to stay away from all parasites.
This comic could be seen as a continuation of the title text from 1693: Oxidation , where that is interpreted as Ponytail ineffectively reassuring Megan that her bug bites should not be a concern.
[Megan and Cueball stand together while Megan loudly scratches her itches and Cueball holds a hand up.] Megan: Argh, bug bites are the worst . I shouldn't scratch, but... so itchy. Cueball: Oh, you know what's great for that? Scratch scratch
[Zoom-in to Megan's head.] Megan: No, don't tell me. Everyone always has weird home remedies that never work. I just want sympathy. Cueball (off-panel): No, this one isn't weird, I promise. It really helps!
[A frame less panel with a zoom-out back to Megan and Cueball. Megan is still scratching loudly and Cueball still holds his hand up.] Cueball: First, take a hot shower. Then dip some ice cubes in vinegar and use them to crush one baby aspirin. Then make some tea, and... Scratch scratch
[Megan walks past Cueball and away from him while Cueball turns and looks after her.] Cueball: ...then, you need a rare French orchid- Megan: I'm going to try a different home remedy where I complain a lot and scratch until my skin comes off. Cueball: Sounds effective. Megan: It's an old family trick.


Juno

Explanation:
This comic was written in honor of the Juno space probe , which made headlines around the world the day before this comic was posted, when it fired its engines and successfully entered into orbit around the planet Jupiter .
It was reported on the day of this comic's release that Juno arrived at its orbit one second off its planned schedule . Since the comic is based on such reports this may explain why this comic was released rather late on the day after Juno's arrival, and also why it was not the subject of the previous comic which was released on the day (fourth of July) when the space probe officially reached Jupiter. This makes it one of several space probe related comics to be released to celebrate the arrival of a space probe to its destination, the previous being 1551: Pluto , which celebrated the arrival of the New Horizon's probe at the dwarf planet Pluto.
Speaking at a NASA press conference, Blondie , standing behind a lectern , announces that Juno has arrived at Jupiter within one second of its scheduled arrival. After traveling 1.7 billion miles (2.8 billion km) such precision is very impressive, which is acknowledged by someone from the press.
The joke is that one of the NASA engineers, Megan , reveals that they actually intended for Juno to arrive at Saturn , but actually arrived at Jupiter with a timing that was still apparently the same within one second. Given the reaction from the spokesperson, she knew this but it was not supposed to slip out.
This is, of course, not true, because if Saturn had been the intended target, Juno would have been off course by 10.25 AU (1 AU is the distance from the Earth to the Sun, or 149597870700 meters) when it arrived at Jupiter. Randall might be making a subtle (or not so subtle) reference to past difficulties NASA has had when converting to metric measurements —in July 2016, Jupiter was 870 million kilometers (540 million miles) from Earth, while Saturn was 850 million miles (1.37 billion km) from Earth (about half the distance traveled by Juno). A similar measurement coincidence was noted in what if? A Mole of Moles . Also, Saturn is a maximum of 1.7 billion kilometers (1.1 billion miles) away from the Earth. For Jupiter, this distance is 968 million km (601 million miles) away. But when traveling between planets, long detours are necessary to reach the goal with a velocity that enables the space craft to go into orbit. So it is just a coincidence that Juno has traveled a distance to get to Jupiter in kilometers that fits with a possible distance to Saturn in miles. The mixup of units mentioned above was directly referenced in 1643: Degrees .
The mix-up of Jupiter and Saturn could be a reference to the book and the film 2001: A Space Odyssey that were written simultaneously. In the book solely written by Arthur C. Clarke they go to Saturn. In the film (from 1968), however, they found it impossible to make Saturn's rings well enough to satisfy director (and co-writer) Stanley Kubrick so in the film version, they ended up at Jupiter instead. (Arthur C. Clarke later made the film canonical when he wrote the sequel 2010 , where the plot would only work with Jupiter, mainly because of its size and partly due to its four big moons especially Europa ).
It's ambiguous who participates in the title text dialogue. There are multiple interpretations.
It should be noted that Juno is mostly linked to Jupiter and not to Saturn (the probe was sent to Jupiter in the real world), which fits best with the "Press speaks first" explanation.
In the title text someone from the press asks another question: wasn't the name of the space probe, Juno , a tip off given the relation to Jupiter? The goddess Juno was the wife of Jupiter the chief deity in the Roman mythology . However her father is Saturn so there are relations to both Gods/planets. Her relationship to Jupiter, however, is most likely more common knowledge explaining the naming of the probe.
However, instead of mentioning this dual relationship one of the three NASA representatives say that at first they even believed it was for Juneau , the capital of Alaska , showing that the engineers did not have a clue about the objective of the mission. They did wonder why a gravity assist was planned to get there but guessed it was a more efficient method. Given that gravity assist is only relevant for interplanetary missions requiring a flyby of a planet, it would never make sense to use one to get between two destinations on Earth. This is so even though Cape Canaveral Air Force Station in Florida, from where the probe was launched, is about as far away from Juneau as it is possible to get inside the borders of the United States. Maybe it was Cueball who was clueless, in which case he may represent Steve from 1532: New Horizons , now confessing to misdirecting another probe.
The mixup of Juno the Goddess and the capital city of Alaska could be a reference to the film Juno where the title character is named after the Goddess as her father is into Roman and Greek mythology (although she calls her Zeus 's wife, Zeus being the equivalent of Jupiter in Greek mythology where Juno would be called Hera ). Later a man asks her " Like the city in Alaska? " to which she simply replies "No!"
Scenarios similar to the likely outcome of Juno using its gravity assist (from Earth) to arrive in Juneau (with unchanged orbital energy) have been discussed in what if? Orbital Speed , Hitting a comet , and New Horizons (see also 1532: New Horizons ).
In the title text someone, likely a member of the NASA team, asks if the name of the space probe, Juno , wasn't a tip off. In Roman mythology the goddess Juno was the daughter of Saturn (though also the wife of Jupiter ). However, instead of mentioning this, someone (presumably a member of the press) replies that at first they had thought the probe was named for Juneau , the capital of Alaska . They had wondered why NASA wanted to use gravity assist to get there, but had guessed that it must be more efficient.
The title text might also be continued discussion amongst the NASA representatives. After being shushed, Megan begins needling the spokeswoman about the huge error NASA made. The spokeswoman then admits to being confused about why the mission was so complicated. Alternatively, the third NASA representative might be Steve , now confessing to misdirecting another probe.
In another interpretation, both lines are spoken by members of the audience. The second would seem to be producing science journalism of unusually poor quality.
[At a NASA press conference Blondie stands behind a lectern with the NASA logo. To the left is Megan and to the right is Cueball, both looking towards Blondie.] Blondie: After traveling 1.7 billion miles, the Juno spacecraft reached Jupiter within one second of its scheduled arrival time.
[A person off-panel to the left comments and all three turns towards the speaker.] Off-panel voice: Very impressive! Blondie: Thank you.
[All three look straight out as Megan comments on the praise.] Megan: I mean, we were aiming for Saturn. Still, nailed the time. Blondie: Shhhh.


Gnome Ann

Explanation:
This comic presents a series of images depicting a female gnome who is known as "Gnome Ann". The humor derives from the fact that the name "Gnome Ann" is a mondegreen of the phrase "no man". (For clarification, "gnome" is pronounced as in the fantastical creature and not as in the Linux-based Gnome desktop system .)
Randall presents the reader with six images (and a title text) captioned with quotations from a wide range of sources, each featuring an instance of the compound noun "no man" being replaced by "Gnome Ann" (and featuring a drawing that reflects this change). There is one proverb, two Biblical quotations, one literary quotation from Cervantes ' Don Quixote , one cinematic reference from the Lord of the Rings (film series) (the line Éowyn said to the Witch-king of Angmar before killing him), one quotation from the opening of a television show ( Star Trek: The Original Series ), and a quotation from a piece of historical rhetoric in the title text.
The Legend of Gnome Ann
[At the beach, between a clock hanging in the air, showing 10 past 10 and the shoreline, Gnome Ann, a woman with curly hair and a black triangular hat, stands with her arms outstretched towards the clock and the sea. For each of the first five panels a text is written within a frame above the drawings.] Time and tide wait for Gnome Ann.
[Gnome Ann running in from the left frame with her arms out chases three Cueball like men running from her towards right. The one closest to her looks over his shoulder at her, the next runs forward "normally" and the last in front throws up his arms in the air.] The wicked flee when Gnome Ann pursueth. - Proverbs 28:1
[Gnome Ann takes the groom's place in a wedding, shoving him to the side. The groom, Hairy with a bow tie, falls while throwing his arms out. The bride stands to the left, in full wedding dress, showing no reaction.] What therefore God hath joined together, let Gnome Ann put asunder. - Mark 10:9
[Gnome Ann sits in a yoga position meditating on a big rock in a desolate area with small rocks on the ground around the big rock.] Time ripens all things; Gnome Ann is born wise. - Miguel De Cervantes
[The starship Enterprise from Star Trek is seen from behind as it flies to the right, chasing a smaller craft. In this panel the frame with text is shown to emanate from Enterprise with a zig zag arrow pointing to the starship.] Enterprise: Our Mission: To boldly go where Gnome Ann has gone before.
[The Witch-king of Angmar, Lord of the Nazgûl, from the Lord of the Rings sits on his knees (below the frame) to the left of Gnome Ann, who is preparing to stab him with a sword pointing at his head. She is also holding her other arm out towards him. The Witch-king has a black cloak covering his head and body with a kind of crown with six small spikes shown around his head and one large spike in front. It also goes down on each side of his head showing a gaping hole instead of a face. In this panel the text is spoken by the two characters.] Witch-king: Fool! No man can kill me. Gnome Ann: I Am Gnome Ann!


Pokémon Go

Explanation:
Pokémon GO is an augmented reality (AR) smartphone game, where players walk around the real world, guided by a virtual map sprinkled with Pokémon , trying to find and capture these creatures from the first to fifth generations (i.e. Pokémon from the first to fifth series of games released), then leveling them up and/or evolving them, and using them in battle, similar to the classic Pokémon games for handheld consoles. These Pokémon are randomly placed around the world in the AR format so that they can only be seen through the phone. Randall is playing a prank on all players happening upon his real Pokémon figures as they are so consumed with this new game that they assume that they are from the game, not realizing that they should not be able to see them before they take out their phones, and then after doing this wondering why their phone is having trouble loading them.
Due to the popularity of the Pokémon franchise, after Pokémon GO's release in the United States on July 6, 2016, many fans of the series have been walking around with their smartphones out to capture and battle Pokémon. Some players are so eager to capture rare Pokémon (for example, Vaporeon ) that they will leave their cars amid traffic with the engines running.
Randall jokes that he has replicated the AR properties of the Pokémon in the app (that is, when you encounter a Pokémon, it is a small computer-generated sprite placed over your phone's rear camera image that moves about your screen, giving the appearance of a "real" Pokémon in front of you). Randall's real life plastic models of various Pokémon have been constructed so they would seem to fit on a smartphone screen due to perspective, he has embedded a gyroscope in them so they wobble about their base giving them the appearance of basic computer-created movement, and as a final touch he has added a subtle underlighting which is also part of the game, and gives them a slightly computer-generated look compared to the real world around them. These effects combined fool avid Pokémon GO players into taking out their smartphone to capture the Pokémon for their game, when in fact it is just a toy sitting in front of them, and they should have known this as mentioned above. In this comic Randall displays the Pokémon called Squirtle which looks like a little turtle.
This comic is part of the My Hobby series . In this case, the hobby is pranking players of Pokémon GO by replicating the appearance of the augmented reality mechanic.
In the title text, Randall is still waiting for an update that allows capture of strangers' pets - besides the obvious, playing by the rules of Pokémon only wild (not any with an owner) Pokémon can be caught. However, in the Pokémon Colosseum games, through the use of a specialized device the player steals from the villains, the player can capture other trainers' Pokémon. This is also a callback to an earlier strip wherein Black Hat wishes for a Pokéball that works on strangers' pets (see last entry in 1086: Eyelash Wish Log ).
Pokémon Go was again the topic of 2220: Imagine Going Back in Time more than 3 years later.
[Cueball walks in to the frame from the left. On the sidewalk in front of him is a small Pokémon figure looking like a standing turtle with a long squirrel like tail, known as Squirtle. Lines around it indicate that it is moving forth and back (wobbling), and circle lines below indicate that there is light below it. The exact position of the Pokémon and these lines around it change through all four images, but stays almost in the same position.]
[Cueball takes out his smart phone and points its camera at the Pokémon while looking at the screen.]
[Cueball shakes his smart phone violently up and down indicated with four to five gray drawings of his arm and phone below and above one solid black copy of the hand and phone. There are also two gray lines above and below the outer gray phones to indicate this shaking.]
[Cueball has lowered his smart phone and just stands there looking at the wobbling Pokémon.] Cueball: ???
[Caption below the comic:] My hobby: Building plastic Pokémon with subtle underlighting and a gyroscope to make them drift back and forth, then leaving them sitting around to mess with Pokémon Go players.


Genetic Testing

Explanation:
Cueball has sent a DNA sample to a genetic genealogy company. The implied premise of the comic is that Cueball intended to send his own DNA to one of the several companies that analyze human DNA samples and provide a report as to the genetic history of that person - examples include notable/famous ancestors or relatives, ethnic background, risk factors for certain medical conditions, etc. However, the result that Cueball receives is consistent with a report for a dog pedigree test, breaking down the percentage of certain breeds present in a dog's ancestry. Megan suggests that Cueball has sent his sample to the wrong company. Cueball appears to agree in principle, but (seriously or jokingly - it is unclear) indicates that he intends to hedge his bets and avoid chocolate just in case he actually is, in fact, a dog. Dogs are generally susceptible to poisoning from theobromine , a compound found in chocolates which causes seizures and heart failure in dogs (and many other creatures). Basically, if Cueball really is a dog, then eating chocolate could kill him.
82% or 94% of genes (depending on how you measure it) are shared between humans and dogs. National Geographic erroneously reported that only 5% of human DNA is shared with dogs and mice, which may have misled Randall Munroe. This leads to several possible interpretations of the comic: It is possible (as Cueball suggests in the last panel) that he is, in fact, a dog with excellent human impersonation skills, or that he somehow shares DNA with a dog. It is possible that Cueball mistakenly sent a sample of a dog's DNA (perhaps his own) somehow thinking that is the method of testing his own DNA. Perhaps Cueball submitted his own (human) DNA to a dog pedigree company and their method of testing includes a presumption of dog DNA, and therefore was able to produce this result from Cueball's sample. Or perhaps this comic is a suggestion that some DNA test companies are scams that do not even perform DNA tests, but simply send out arbitrary reports that are not based on any testing.
The title text refers to the fact that certain dog breeds are more or less susceptible to disease. The diseases he mentions, elbow dysplasia , heartworm , parvo virus and mange are several diseases that can end up killing, disfiguring or disabling dogs, but which humans are generally not susceptible to. As noted above, ancestry DNA test results can inform people about their genetic risk factors for disease, either by specifically investigating your own DNA for those risk factors or, more likely (and less costly) by informing of what risk factors are generally prevalent in your ancestry or others people sharing the same ancestry as you.
After this comic was published, it was revealed that a testing service issued reports determining that First Nations ancestry was detected in sample DNA taken from a dog.
[Cueball and Megan are talking to each other.] Cueball: I sent a DNA sample to one of those "Trace your ancestry" projects. Megan: How legit are those? Cueball: No idea. I just figured it'd be fun.
Six weeks later... [Cueball walks towards Megan with a letter in his hand.] Cueball: Sweet, got my results back. Megan: Ooh, share!
Ancestry Report 48% Labrador Retriever 35% Beagle 12% Cocker Spaniel 5% Other
[Megan is holding the report.] Megan: I think you sent your sample to the wrong service. Cueball: Just in case, I should probably start avoiding chocolate.


xkcd Phone 4

Explanation:
This is the fourth entry in the ongoing xkcd Phone series , and once again, the comic plays with many standard tech buzzwords to create a phone that sounds impressive but would actually be very impractical. The previous comic in the series 1549: xkcd Phone 3 was released just over a year before this one and the next 1809: xkcd Phone 5 was released almost 8 months later.
From the top-left, going clockwise:
[An image of a smartphone featuring wings is shown. Clockwise from the top left the labels read:] 18,000 μAh nickel-lithium-iron battery (non-rechargeable) Subwoofer "Dog whistle" Non-porous, washable WebMD partnership: Cough-activated feature reads aloud a random diagnosis for "coughing" Wings Beveled bezel Bezeled bevel Seedless Water resistant down to 30 meters and below 50 Turing-complete Gregorian/Julian calendar switch SpaceX impact protection: When dropped, phone lands on barge Parallel port 12 headphone jacks Onboard cloud New BrightGlo TM display incorporates genetically spliced jellyfish protein (should have used the glowing genes, not the stinging ones) ✓ Certified Software-defined Exposed ductwork Voice interaction: Siri, Cortana, Google Now and Alexa respond simultaneously
[Below the phone:] Introducing The xkcd Phone 4 Did you know "4" is "IV" in Roman numerals? ®© ™


Dehydration

Explanation:
This comic plays on the idea that there is little to no consensus in the scientific community with regard to the amount of water a person should drink per day. In the first panel White Hat presents Cueball with an innocent and sensible suggestion (although controversial) that people should drink six or more glasses of water per day. In the second panel, more characters join the discussion, an off-panel voice claims the most common misconception of eight glasses a day, a number which is not supported by scientific research. Ponytail again goes two higher with ten highlighting the existence of a wide range of so-called 'optimum' liquid consumption 'rule-of-thumb'. Implied here is the variety of health-related books, articles, blogs or other literature published that self-proclaims an optimum drinking formula.
The first sign of absurdity also arises here in the second panel when Black Hat posits that we need 5 glasses of water every minute. This equates to 7200 glasses of water a day, and using an often cited " standard definition of a glass " being equal to 8 oz (236 ml), Black Hat is suggesting that we should each drink 1.7 cubic meters (1700 liters) of water a day, curing dehydration but also causing water intoxication . This is a typical Black Hat kind of statement that he uses to further emphasize the absurdity of the problem at hand.
Some time later Megan , despite having read through all studies on dehydration (or low-grade dehydration in particular), still has not come to a solid conclusion. She becomes dizzy, admitting that she's been so focused on her work, she has ironically forgotten to eat or drink . Her personal experience with dehydration prompts someone off-panel to get some water, but since she couldn't find any consensus in her research, she asks how many glasses they should bring her. Presumably to avoid the question of "how many glasses" entirely, Cueball finally suggests that she should drink straight from the tap, a (tenuously) sincere suggestion seeing her dehydration and following the good advice to drink when you are thirsty until that state has been absolved. In the title text of 1744: Metabolism , released less than 3 months after this one, Cueball mentions how he starts to feel bad if he refrains from drinking, just like Megan here.
The title text contains a mix-up between two often stated intervals; drinking eight glasses of water per day (which makes no sense, see above) and changing the engine oil every 3000 miles (almost 5000 km) which may be a good rule, but not a necessity. Obviously it's impossible to drink 3000 glasses of water, and changing the oil every eight miles (about 13 km) would make driving a car very impractical.
The subject of this comic has been graphed in 715: Numbers and mentioned in the what if? Soda Planet :
Later, in the what if? Faucet Power , Randall comments on the preference for even numbers in the graph, and writes:
How many glasses is "some water" remains an open question.
Beret Guy and Megan are participants of a thought experiment concerning glasses of water and vacuum in the what if? Glass Half Empty .
And the six glasses of water that this comic began with is also mentioned later in 1853: Once Per Day .
This is a rare example of a normal xkcd comic of few panels manages to use five of the seven major characters who actually interact. It is the first comic where Black Hat has spoken (or directly interacted) with White Hat. Until this comic, they have only appeared together in complicated/large drawings where there is no interaction between the two. The only other time this has happened is in 1881: Drone Training .
[White Hat and Cueball standing together.] White Hat: Many people are mildly dehydrated. And don't realize it. You should drink at least six glasses of water per day.
[A voice comes from off-panel to the left as Ponytail enters from the left and Black Hat from the right in this frameless panel.] Off-panel voice: No, eight glasses! Ponytail: I heard ten. Black Hat: You need to drink at least five glasses of water per minute.
[Megan is standing to the left holding a book or a thick binder along her side while holding up a finger with the other hand. A question comes from off-panel to the right. Above her a caption is written in a small frame that breaks the top of this panel's frame:] Later: Megan: Okay, I just read through every study I could find to try to figure out whether low-grade dehydration is even a real thing. Off-panel voice: What did you learn?
[Megan looking downwards, has two starbursts a circles and two dots above her head signifying dizziness. Cueball stands to the right as another voice comes from off-panel to the right.] Megan: If you spend all day doing research and forget to eat or drink, you start to feel pretty bad. Off-panel voice: I'll get some water. Megan: But how many glas - Whoa, feeling dizzy. Cueball: Maybe you should just drink straight from the tap.


Inflection

Explanation:
While walking, Megan tells Cueball that in inflected languages — such as German — changes in the spelling of a word changes its meaning, in a predictable way. Megan exemplifies this with how plural forms of nouns are created by sticking an "s" at the end, and past tense of a verb is done by the suffix "ed". Megan then explains that this works well in languages which build on alphabets .
She continues to explain that their language family belongs to those that are inflected, but the English branch is becoming less inflected than it used to be. Specifically this explains why English does not have so many Latin conjugations . A conjugation is a pattern of inflections, describing how a particular group of verbs is altered from its root form to represent different grammatical cases. Only verbs have conjugations (are conjugated ), nouns, pronouns, and adjectives are described by declensions (and are declined ). All inflected languages can be described by conjugations and declensions, although Latin is one of the most commonly cited, perhaps because Latin grammar was taught for centuries by monotonous rote learning of the conjugations and declensions.
A typical Latin conjugation would be the verb amare , to love.
(The English singular uses archaic forms to highlight the number and person.)  A complete conjugation includes all tenses (Present, Imperfect, Future, ...), both voices (Active & Passive), and all moods (Indicative, Imperative, Subjunctive, ...). Other parts of speech — infinitives, participles, gerunds, and so forth — are needed to completely define the verb, but are not usually considered to be part of the conjugation.
Cueball then asks Could that mean that English writing might be ripe to become more pictographic? Instead of using traditional words, Megan replies with three emojis "Thumbs up" (like), "Applause", and a smiley — thus showing a pictographic version of the writing which has become more popular in the last years. Emoji has become a recurring theme on xkcd.
The writing systems of many languages have both pictographic and ideographic origins. "Pictographic" means that they are pictures of some thing that will remind the reader of either the pronunciation or the meaning of the word. The letter "A", for example, originated from a word meaning "ox", but was meant to remind readers of the glottal stop (it wasn't until the Ancient Greeks, who didn't have the glottal stop as a distinct phoneme, got a hold of the Phoenician version that it was transferred to the vowel(s) it is today). "Ideographic" means that they are designed, through pictures, to illustrate some idea. An example would be a "No Smoking" sign, where a red circle with a diagonal line is an abstract representation of "no". In fact, the three emojis used in the third panel of this cartoon are all ideographic, not pictographic, under this definition. "Thumbs up" (like), "Applause", and the smiley, are all emojis that remind us of a concept of approval.
Egyptian hieroglyphics contain many pictorial elements, some of which are pictographic in the sense that they are meant to represent the thing that they picture, but many are more abstract (ideographic) or are used for their phonetic value (as "A" was used in early alphabetic systems). Similarly, in the Chinese character writing system, many of the elements have pictographic or ideographic origins; but they are often, and even usually combined in ways that are phonetic and not related to the pictures that were the origins of the characters.
Early modern English (think Shakespeare or the KJV Bible) used more forms for the tenses than we do today, which can help illustrate the trend away from inflected forms. In contrast, verbs in English today are often conjugated with auxiliary verbs. See below for details on modern verb conjugation in English .
The title text points out that some intentional misspelling are used in Internet slang to alter the meaning of a word: "what" becomes " wat " to express confusion, disgust or disbelief. The title text also uses typographical variation to emphasize the word MORE by using all capital letters. Such emphasis is difficult to show with inflected language alone.
This comic is referenced at 4500 BCE in huge chart of 1732: Earth Temperature Timeline . According to that comic it was at that time inflection was invented but just to tease future students so they have to remember a zillion verb endings .
[Cueball and Megan, holding a hand up, are seen walking together from afar in silhouette.] Megan: Inflected languages change words to add meaning, like "-s" for plurals or "-ed" for past tense. Megan: Alphabets—where symbols stand for sound instead of words—work well for them, since you can show the changes through spelling.
[Zoom in on the two as Megan turns her head back towards Cueball and spreads her arms out.] Megan: Our language family is inflected, but the English branch has lost most of its inflection over the millennia. It's why we don't have all those Latin conjugations.
[Cueball speaks as they walk on and Megan replies with three orange-yellow emoji: Thumbs Up Sign pointing right, Clapping Hands Sign pointing up left with two times three small lines to indicate the clapping and Smiling Face With Blushing (red) Cheeks and Smiling Eyes. Below given the closest match possible as of the release of the comic.] Cueball: Could that mean English writing is ripe to become more pictographic? Megan: 👍 👏 😊
In the table below is a sample of a modern verb conjugation in English.
In all of these conjugations, the only inflections on the main verb "walk" are "-s", "-ed", and "-ing". The highly irregular helper verbs, "be" and "have", have somewhat more interesting inflections. And although this table shows only the third person, the first and second person would only introduce the helper verb "am" (as in "I am walking"); similarly, the table shows only the indicative mood, but the subjunctive and imperative moods would not introduce any additional words, and the conditional mood would only introduce the helper verb "would" (an inflection of the irregular helper verb "will") without any additional inflections on the main verb "walk". If instead we made this table in Spanish (for example), then there would be many more inflections on the main verb (12 in the third-person indicative alone, 45 including all persons and moods, if I didn't miscount).


Walking Into Things

Explanation:
Cueball comments on the rate of his walking into things while distracted by various stimuli, comparing it to a controlled study where the aim is to research whether he is most likely to bump into something while looking at a book, at his phone, or staring at the sky (something Randall does a lot with his interests in astronomy, optical phenomena, weather phenomena and kites).
Megan replies that if this is the case, the rate of the "control group" colliding with things is also weirdly high. In Cueball's metaphor, the "control group" would be his walking around without being distracted, so you would expect him not to collide with anything when able to give his full attention to where he's going. Thus, Megan is implying that Cueball is simply clumsy or easily distracted by other events or his own thoughts, and that his walking into things has little to do with whether he's looking at his phone, in a book or at the sky. Cueball responds defensively, saying that "walking [without bumping into anything] is hard, okay?"
Walking actually is a difficult task, as can be observed when trying to teach a robot how to walk, or the time it takes for children to learn it and the way that a baby's first steps are celebrated as an achievement and a milestone in their development.
In the title text, Randall remarks that his childhood spent walking around with his nose in a book has prepared him "unexpectedly well" for today's world. Years ago, walking around while staring at something in your hands — such as a book — was considered odd, antisocial and dangerous, and was mostly the province of bookworms and nerds. Yet now, it's commonplace for people to walk around staring at their phones. This, ironically, makes those "antisocial" people who grew up used to walking around while reading the best-adapted to navigating while using a smartphone.
[Meagan and Cueball, holding a smartphone in his hand, walk through a landscape with patches of grass. They are just passing behind a stump of a tree, a small bush is in front of them and there are two rocks on the ground which extends to rolling hills in the distance under a clear sky with three small white clouds to the right and two seagulls drawn as lying down 3 to the left with four more birds further left and much further away.] Cueball: My life is basically a big controlled trial of whether I'm more likely to walk into something while looking at a book, my phone, or the sky.
[Zoom in to Megan and Cueball while they're still walking, no background is shown. Beat panel while she ponders his statement.]
[Megan and Cueball still walking.] Megan: The weird thing is that the rate for the control group is so high. Cueball: Walking is hard, okay?
The second word in the first panel looks like "UFE", but it's actually "LIFE" with bad 1015: Kerning .
At the time the comic was released, Pokémon Go has been gaining popularity, with many people raising concerns about the dangers of walking around while staring at a phone screen. (See 1705: Pokémon Go released two weeks before this).


Snapchat

Explanation:
Snapchat is a photo-sending app that allows the receiving user to view the photo (known as a "snap") only within 24 hours of its posting, and for only 10 seconds before it is deleted. The Pulitzer Prize is famously awarded for exceptional journalism and photojournalism (there are many categories; see here ).
Cueball reads that the Snapchat Pulitzer Prize has just been awarded but then, when Megan states that she heard the picture was really good, Cueball becomes disappointed because he realises he has already missed out on the chance to see the prize winning entry due to the temporary nature of Snapchat. Note that Megan also missed the opportunity to see the snap.
A given snap can be sent to a semi-public "Story" and the user decides how long any user can see the snap in a range from 1-10 s . In principle, any specific snap is only accessible for 24 hours even if it is a story. A committee of users could have more than 10 seconds to access the snap, by viewing in sequence. Given the time it might take for a committee to decide which snap wins the prize, it is realistic that Cueball learns about the winner after the 24 hours is up; Thus even a user following the outcome might not be able to see the winning entry after that time. In practice it is possible to circumvent the Snapchat rule and take a screen shot or in other ways save the content of the snap. In the case of a Pulitzer Prize winning photo, someone would probably have saved it, if it was in real life. On the other hand, the only way for the photo to be recognised as a snap, eligible to win the prize, would be if no one could see it for more than 10 seconds. So one of the possible rules might be that any picture which was saved would not be able to win the prize.
The title text extends this ephemeral nature of Snapchat's content to the prize awarded for it: The other Pulitzer prizes are announced annually in April and awarded in May (except for 2016, the centennial year, when an awards dinner will be held in October). The Snapchat Pulitzer Prize alone must be awarded as quickly as possible after the winner has been decided, before the prize committee forgets what the winning picture looked like. This of course underlines how silly this idea is, because only images seen during the assembly of the prize committee can be seen and remembered, and it is not possible to arrange this based on any knowledge of when a Pulitzer Prize "worthy" snap will be released.
Randall could be making fun of Snapchat (see the title), and the idea that you cannot save the images for later; As mentioned regarding screenshots, it is actually very easy to save pictures from Snapchat - to many a user's regret after having sent something very personal, such as naked pictures of themselves. The comic could also be seen as mocking the Pulitzer Prize for having too broad a spectrum of categories. Alongside the (photo)journalistic and prose awards, the Pulitzers also honor a variety of artistic pursuits, including Poetry, Drama and Music.
The new medium of Snapchat is certainly a hybrid form of art and information/opinion dispersal, both at its best and at its worst, but it is too ephemeral for awarding prizes to be logistically possible even if it were taken seriously enough for someone to want to award them.
The very next comic, 1712: Politifact , features an organization which was awarded the Pulitzer Prize for National Reporting in 2009.
[Cueball and Megan standing together. He holds a smartphone in his left hand and looks at it.] Cueball: Oh, the Pulitzer Prize for Snapchat was just awarded. Megan: Yeah. Megan: I hear the photo was really good. Cueball: Aw, maaaan ...


Politifact

Explanation:
The website PolitiFact.com rates political claims based on how true they are. The rulings from the Truth-O-Meter™ at PolitiFact are:
This comic presents a woman wearing a white hat with a press pass in the hat's band. She is calling herself "PolitiFact" - either pretending to come from PolitiFact.com or she is representing a personification of the website itself. She is obviously annoying Megan and Cueball by first breaking and entering and then rating everything they say on the Truth-O-Meter. (She is using the official logo of PolitiFact as her name, and since they write their name PolitiFact her name should also be written like this, even though Randall has named the comic Politifact with all lower case letters and also uses it like this in the title text.)
When Megan, apparently just having gotten out of bed, says she had trouble sleeping, the PolitiFact.com woman (henceforth simply PolitiFact) appears at an open window and observes that Megan is telling the truth with the rating of " Mostly True! " (So according to PolitiFact she did not sleep well most of the night, but may have slept OK for some parts of the night.)
Megan appears distressed, which is not improved when PolitiFact enters their house through the window. Megan gives chase to PolitiFact, passing by Cueball, whose comment Not again makes it clear that this is not the first time PolitiFact has annoyed them in this way. Megan swears that she had locked the window, though PolitiFact gives that claim the rating of " False! " as PolitiFact herself demonstrated. Although entering someone's house against their wishes is illegal, regardless of how entry is achieved, Megan's failure to secure the window means that PolitiFact cannot be charged guilty of breaking and entering - and, more pressingly, has made it easier for PolitiFact to annoy them.
Cueball asks her to leave as Megan chases her through the house. After the chase, PolitiFact ends up hiding under the couple's bed; Cueball's claim that PolitiFact "can't stay under there forever" is promptly rated " False ". Megan's remark, however, that no one likes PolitiFact, is rated " Mostly True! " This exchange is likely metaphorical just as much as it is literal — Randall's PolitiFact acknowledges that what she does annoys people, but she keeps on doing it anyway.
As for metaphors, Megan is likely commenting on the popularity of the website, which Randall's PolitiFact is no less correct about. People become very defensive when claims they make in political discussions are debunked by PolitiFact.com. There is a phenomenon where the people most influenced by an erroneous claim are the least likely to believe a fact checker. For example, The Washington Post shut down their internet rumor fact checker because, "institutional distrust is so high right now, and cognitive bias so strong always, that the people who fall for hoax news stories are frequently only interested in consuming information that conforms with their views — even when it's demonstrably fake." Simply put, people like the idea of a fact checker until they disagree with it.
PolitiFact.com has been accused of being both liberally biased and conservatively biased at various times and has angered politicians on both sides of the aisle. The summary statistic "rulings" are especially troublesome; often the critics will agree that the information presented by the fact check is correct, and may agree that all relevant information has been included, but will disagree as to the importance of context omitted by the original speaker or the interpretation of ambiguous language.
The title text makes a play on PolitiFact.com's most untrue rating, "Pants on Fire!" - a reference to the childhood accusation " Liar, liar, pants on fire! "
In the title text either Cueball or Megan says to the other that they have lit the smoke bomb and rolled it under the bed near PolitiFact (seems they have discussed this first). When it goes off it apparently manages to ignite PolitiFact's pants - thus, PolitiFact's pants are literally on fire and she yells "PANTS ON FIRE!". Cueball has thrown smoke bombs before while in a relation with Megan, see 486: I am Not a Ninja , so it would be likely he had a smoke bomb on his person for immediate use.
Alternatively, either Cueball or Megan just says this as a threat (they could even roll a non-bomb object under the bed and maybe they have talked out loud about the idea of using such a bomb before) and they could try to make the loud fwooosh sound themselves to simulate that the bomb going off. Then they would be telling an outright lie that would be rated as "Pants on Fire!". The fact that the fwooosh is located outside of the "quotation marks", is no indication as the sound is not part of the quote. Also the fact that "PANTS ON FIRE" is yelled, rather than calmly delivered in the fashion of her other judgments, is not necessarily any indication that this is not the case, since a threat that is so blatantly a lie as to warrant such a rating should be proclaimed out loud.
It is also possible that PolitiFact's rating is a meta check of the title text itself ; because the scenario described is not illustrated as is the rest of the comic, it has not happened, and thus is blatantly false.
It may be a coincidence, but PolitiFact.com was awarded the Pulitzer Prize for National Reporting in 2009 for work done in their first full year of work (after it was started in August 2007), and this comic was released right after 1711: Snapchat , which hinges on the existence of little-known Pulitzer Prize categories.
PolitiFact was later referenced indirectly with a fact check in 1790: Sad which is rated mostly false , and directly in the title text of 2129: 1921 Fact Checker , about, well... fact checking.
[Megan with messy morning hair is walking right and rubs her eyes.] Megan: I did not sleep well last night.
[A woman with hair like Megan (but a bit longer) wearing a white hat with brim and a small white card attached to the hat's belt (like a press pass) crawls up on the pane of an open window. She begins all her sentences with the word PolitiFact. When she says this it is written in the color and style of the PolitiFact.com logo with blue Politi and red Fact . Megan has just walked past the window and has turned to look at the woman. She is still holding one hand up and her hair is still messy.] PolitiFact: Politi Fact says mostly true! Megan: Oh no...
[In a frame-less panel Cueball is walking right, while Megan, arms stretched out and hair flowing out behind her, runs by him chasing PolitiFact who is running with a hand up to hold her hat in place, hair also flowing out behind her.] Cueball: Not again. Get out of here, PolitiFact! Megan: I swear I locked that window. PolitiFact: Politi Fact says: False!
[Cueball and Megan, looking downwards, are standing at the foot of a well made bed with two pillows, and the bedsheets drawn tight. PolitiFact's voice emanates from a starburst at the edge of the shadow under the bed.] Cueball: You can't stay under there forever. PolitiFact (voice from under bed): Politi Fact says: False! Megan: Nobody likes you, Politifact. PolitiFact (voice from under bed): Politi Fact says: Mostly true!


50 ccs

Explanation:
This comic presents a busy day in the clinic for doctor Ponytail , who orders 50 ccs from a nurse (probably Megan who walks in front of her rather than Cueball walking away behind her), all the while everyone is hurrying along the hall. This could be a typical scenario in a busy hospital. However the pun is that the 50 ccs are not medicine but should be used to write "hiccup vaccine" 25 times.
In medicine, "cc" usually means " cubic centimeter ", and is often called that by medical personnel. A cubic centimeter is equal to 1 ml (milliliter), so "50 ccs" usually means 50 ml of a certain medicine. In this case however, the doctor has not told the nurse to bring 50 ccs of any given medicine; instead, she needs to write "hi cc up va cc ine" 25 times, with both words containing the letter combination "cc", so she needs to write that combination 50 times.
That is the joke, that the 50 ccs literally means the two-lettered 'cc' fifty times.
There's no conventional vaccine against hiccups . However, performing tasks meant to distract one's self is a method to stop hiccups. Therefore the act of writing "hiccup vaccine" 25 times would itself comprise one more of those hiccup cures that never seems to work. What these techniques all rely on is that they all force one to hold one's breath, thus resetting the diaphragm from its out of sync spasms. But if Ponytail has discovered a vaccine that does somehow cure or prevent hiccups, then this unexpected result is worth reporting in medical journals and seeking grants for further study. Thus, wanting to write about it 25 times is understandable!
The title text text refers to a fictional event with four words containing "cc" (ra cc oon, a cc ident, a cc ordion, ba cc hanalia), which means she needs to write "cc" 100 times. Referring to the 50 ccs from above, this would be a double dosage.
Although the words of the sentence has been chosen based on their cc's the sentence is quite interesting in itself:
So here there is talk of a wine festival with music played on accordions that has had an accident involving raccoons, in addition to the need for vaccine against the hiccups.
A similar doctor Ponytail is shown in 883: Pain Rating also along with Cueball and Megan and just with Megan in 996: Making Things Difficult .
[Ponytail in a doctor's coat, walks right while reading from a clipboard, passing Cueball walking the other way while she talks to Megan walking in front of her.] Ponytail: Nurse, bring me 50 ccs! Ponytail: I need to write "hiccup vaccine" 25 times!


Volcano Types

Explanation:
This comic presents a table of 12 different types of volcano. Split into 3 rows, the first 4 are authentic types of volcano; while the remaining 8 are parodies, one not even trying to represent a volcano but shows a real animal in its inverted trap cone.
Volcanoes have featured in many xkcd comics, most prominently in the left part of the world (the Lord of the Rings section) of 1608: Hoverboard . This comic's volcano looks like it could soon turn into a Somma volcano.
The title text refers to a famous scene in Star Wars: Episode VI - Return of the Jedi where Jabba the Hutt intends to feed Luke Skywalker to the sarlacc , an underground creature that builds a huge funnel trap similar to that of an antlion. Jabba's distinctive sail barge features prominently in that scene, and when Randall comes upon an antlion he can't help himself starting to build a scale model next to the antlion's inverted cone. Given how small antlions are, this will be very difficult to do, see for instance 878: Model Rail .
[Twelve drawings in four rows of different "volcano" types, the first four real, and some not even volcanoes of any sort, real or fake. Below each panel is a caption with the name of the drawn volcano. Some of the volcanoes have labels or sound written inside the panel. Each of the volcanoes has a baseline for the ground going straight a short distance over the bottom of each panel. All 11 volcanoes lie on top of this line, but some show the inside of the volcano going further into the ground.]
[Standard cone shaped volcano, with straight sides sloping up to a triangular shape, but with the tip of the cone cut off to form the central jagged edged crater. White smoke rises straight up and then drifts to the left forming three separate clouds.] Cinder Cone
[Flat rounded shaped volcano, as a part of a circle. There is not a real crater visible but from the center a thin plume of smoke rises up, drift drifts to the left and forms a small white cloud.] Shield Volcano
[This is the largest volcano. The tip of this volcano is similar to the first volcano, but with more uneven slopes and a bit smaller. The tip is clearly separated from the bottom section by a thin jagged line, and below the sides of the volcano decreases their slope, so they are less steep than the tip. Black smoke rises straight up from the crater and then drifts to the left in four thin lines.] Stratovolcano
[A wide volcano spans the entire panel, with a large central crater, with a bottom baseline far above the ground level. Just left of the middle of this crater is a standard smaller volcano cone, very similar to the shape of the tip in the previous panel. Even the smoke from this cones small crater is similar to the previous panels.] Somma Volcano
[The central part of this volcano is the same shape as the previous panel. This could be a zoom out, revealing that the large crater, is at the center on an even larger crater, which again is at the center of a crater that spans the panel. A plume of black smoke rises from the centeral cones crater, and drifts left as five white clouds.] Metasomma Volcano
[A perfect cone-shape, triangular and steep, with checkered ice cone waffle texture, even with a line indicating where the waffle has been a folded. It looks like a road up the volcano. Black smoke drift up from the sharp tip, no crater, and drifts left forming a small cloud separated from the rest of the smoke lines.] Waffle Cone
[Standard cone as in the first, but zoomed in so it fills the panel from left to right. The volcano's top has been cut much further down leaving a wide crater from which lava is pouring down the sides in large rivers of different width and length. To the left one long river has almost reached the ground. Cueball is running down the left side, and Megan is running after another Cueball with his arms up on the right side. There is a label with an arrow pointing to the lava:] Label: Baking soda and vinegar Science Fair Cone
[Standard cone like the previous, but with more jagged sloped and crater. This volcano erupts with a large explosion with fire and smoke coming out in all directions above the crater. A large sound is written above the explosion:] Sound. Doooooot Doot Cone
[This is not a volcano, but the inverse, a cone down into the ground, the ground level no above the center of the panel. The slope down into this cone hole is straight, the ground above is more jagged. At the bottom of the hole sits a small animal with six legs and an open mouth piece sticking up out of the hole. Its fat body is hidden under the ground along with its legs.] Antlion
[Standard volcano cone like the previous volcano. It erupts and the central part shows how the erupting material comes up from below ground level (below the line at the bottom in which the cone it self stands). The erupting material is white rocks on black background. At the top several rocks is blown out of the crater top. The sides of the volcano is filled with blobs small and large, and stones rolling down the sides. There are two labels, each with two arrows. The first labels arrows points to the side of the volcano, the second labels arrows points to the erupting material inside and outside the volcano:] First label: Lava Second label: Solid rocks Inverse Volcano
[Standard cone like the doot cone, with a crater that bends down in the middle. From this crater eight white ghosts with two black eyes are rising, like the smoke, drifting left. The highest ghost is just reaching the edge at the top left of the panel. The lowest ghost is still inside the crater with its wavy lower parts.] Ghost Vent
[A standard cone like the doot cone. At the top there is lave over the outer edges, some of it running down the side. The inside of the volcano has been drawn like in the inverse volcano, so it is clear that the magma inside the volcano comes up from below ground level (below the line at the bottom in which the cone it self stands). There are two labels that contradicts the description above. The top label outside the volcano points to the lava with an arrow, and the bottom label inside the volcano points to the magma:] Top label: Magma Bottom label: Lava Pedant's Bane


Household Tips

Explanation:
This is another one of Randall's Tips , this time with a series of household tips. The comic is a continuation of 1567: Kitchen Tips , which had four kitchen tips and then a household tip in the title text.
The comic shows Cueball explaining many things one should already know (and are likely already doing without needing to be told), but telling them like most people usually never do it to comedic effect. Below is a list of the five household tips given:
To conserve water, try turning off your shower before leaving home : Implies that the shower would "normally" be on at all times, which would be very wasteful. The what if? article " Faucet Power " illustrates similar wasteful and destructive water use. This may be a reference to the common recommendation that people should unplug appliances when they are not in use, as opposed to simply turning them off, as some devices have a "standby" mode that still uses up a small amount of electricity.
Sick of changing those smoke detector batteries? Eliminate any fires in your house and the batteries may last for months or years! : A smoke detector on standby consumes much less power than one constantly ringing, since standing by only requires that a detection circuit (which draws little current) be on and an LED flashes a few times a minute (which also consumes very little power), while a buzzer used to sound the alarm uses much energy by comparison. The sentence implies that some people have their fire alarms beeping at all times due to their ongoing fires, and then stop up to change the batteries when they stop working. It is surreal that Cueball would have fires just around his house and not be remotely worried.
Of course, keeping one's house fire-free at (mostly) all times is usually done because of other benefits than just saving on batteries, such as preventing fire and smoke damage to valuable property, infrastructure, and human bodies. [ citation needed ]
Tired of clogged toilets? Try leaving the lid on the upper chamber and use only the lower bowl! : The "upper chamber", the toilet's cistern tank, delivers plain water to the lower bowl at speed to flush the latter. As such, the pipes that direct the water down are not wide enough for waste to pass. There is typically a lid on the upper tank, because it isn't intended to be used; however, access is occasionally needed to fix or replace the flushing mechanisms. The lower bowl, as one should be familiar with, is the one intended to receive solid waste or defecation [ citation needed ] and is connected to the plumbing by pipes wide enough for this purpose.
Fresh air doesn't have to be expensive. Many windows can be slid up to create a temporary hole without the usual cost and cleanup! : This suggests that the people he appeals to typically smash a window (or a wall) to get fresh air, hence the clean up and expensive replacement of the window, once enough fresh air has been obtained.
To make your shoes feel more comfortable, smell better, and last longer, try taking them off before you shower. : People typically remove all their clothing, including and/or especially shoes (except perhaps for some lightweight sandals to protect the feet in public showers), when showering, so while it is certainly true that removing one's shoes before showering will allow them to last longer and stink less (since shoes that have little opportunity to dry produce malodorous molds), this is not in any way a novel idea.
[Cueball is standing outside a bathtub with the shower curtains partly drawn aside hanging outside the tub. The shower head is dripping water as Cueball reaches in turning the closest of the two taps. Below these there is a faucet. There is water on the floor at the bottom of the tub and a pool of water behind Cueball.] Cueball: Hi everyone! I'm back with more household tips. To conserve water, try turning off your shower before you leave home.
[Cueball is holding a bucket and pours water out of it to the right. The water still hangs in the air over a small fire with four flames on the floor. A similar fire is behind him to the left, except it seems thre is a burning item in this fire, and a single flame is on the floor between that and Cueball. A smoke detector (off-panel) goes off in the background as indicated with lines and sounds.] Cueball: Sick of changing those smoke detector batteries? Eliminate any fires in your house and the batteries can last for months or years! Smoke detector (off panel): Beep beep beep
[A frame-less panel shows a a toilet with the toilet seat up and also the lid has been removed from the cistern at the top. It is hanging in the air above and behind the cistern. There is an X with an arrow pointing towards the cistern and a checkmark with an arrow pointing towards the toilet bowl.] Cueball (off-panel): Tired of clogged toilets? Try leaving the lid on the upper chamber and use only the lower bowl! X ✔
[Cueball holding a hand up is standing next to an open window where the bottom part has been slid almost up to the top.] Fresh air doesn't have to be expensive. Many windows can be slid up to create a temporary hole without the usual cost and cleanup!