Coronavirus Name

Explanation:
This comic is the first comic in a long series of comics about the COVID-19 pandemic . For several weeks in a row, all comics were related to this pandemic.
This is thus Randall's first take on the COVID-19 pandemic. As of the publication date (March 2, 2020), the pandemic had infected more than 90,000 people, and had caused more than 3,000 deaths.
Coronavirus is a category of viruses named for their appearance, which is similar to a halo or crown, and includes four different viruses which can cause the common cold in humans. However, the virus itself is not called COVID-19, but is called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). So calling the virus or disease "coronavirus" is like calling a specific strain of flu The Influenza virus . However, since the new coronavirus is so hyped in the media it has attracted so much attention, so the name "coronavirus" has become associated with COVID-19, making it difficult to discuss other types of coronaviruses later on.
As of March 2, 2020, COVID-19 in China has a 20% hospitalization rate and a 2% death rate by current estimates, compared to a typical rate of around 0.1% for the flu in the US .
In this comic, researchers Ponytail , Megan and Cueball are discussing that it is by now too late to try calling the disease its official name COVID-19, as the name coronavirus has stuck. Cueball reacts with dismay, since there are many other types of coronaviruses.
To illustrate that Cueball's complaint is excessively pedantic and inconsequential, Ponytail — rather than using a more real-world analogy — compares the coronavirus naming to a giant car-eating spider living on top of the skyscrapers of the town, which people similarly refer to generically as simply "The Spider," even though that is not the most technically-accurate name (it is technically a mutated Tigrosa annexa wolf spider ). Everyone knows what you mean when you say "Coronavirus", as they do when you mention "The Spider".
The comic then goes on to poke fun at itself by treating Ponytail's example as a real concern, as Megan then asks if they should not also do something about the spider. But Ponytail and Cueball agree that they can only tackle one problem at a time, and coronavirus takes up all their time. Ponytail further notes that she simply began altering her route to circumvent the location where The Spider has taken up residence, as evidence that the Spider issue can be easily avoided, and is therefore not an immediate concern.
The title text references the health advice that people avoid touching their face with unwashed hands, in order to prevent infections that they picked up by touching things from entering their mucous membranes. (It's a lot easier for an infection to enter the body through the inside of your nose than your hands.) It is likewise quite important to keep the giant spider from touching your face, but for the dissimilar reason that it might bite and eat you.
Notably, the rename to COVID-19 did eventually catch on as the default description of the disease caused by "The Coronavirus" SARS-CoV2.
[Megan is carrying a box with biohazard symbols on it towards a desk where Ponytail (wearing safety glasses) is working on a laptop, across from Cueball (also wearing safety glasses) who is putting a test tube into a PCR machine. There's also a flask on the desk.] Ponytail: Feels like we missed the window for the "COVID-19" renaming. "Coronavirus" is just too catchy. Cueball: But it's not specific! There are a lot of coronaviruses.
[In a frameless panel, Ponytail (still wearing safety glasses) is pointing at a screen or picture showing a modern city skyline with a large spider crawling across three of the high-rise buildings.] Ponytail: I think it's fine. It's like, you know the giant spider downtown that sits on the buildings and sometimes eats cars? I think technically it's a mutant T. annexa wolf spider, but everyone is just calling it "the spider" and we all know what they mean.
[Back to the setting from the first panel. Megan is standing and Ponytail had turned towards her and Cueball has stepped back from the machine.] Megan: I've been meaning to ask, what's with that spider? Should we...do something? Ponytail: Honestly I've been too busy with the virus stuff to look into it-I just changed my commute to avoid Main St. Cueball: Yeah, that's fair. One thing at a time.


Self-Isolate

Explanation:
This comic is the second comic in a row in a series of comics about the COVID-19 pandemic .
In this comic, Cueball is watching television and hears a suggestion that people may need to "self-isolate." This refers to the practice of isolating infected individuals, to keep the disease from spreading. If the pandemic grows more severe, going out in large crowds could also be discouraged, to avoid being infected by those around you.
According to the HHS , both quarantine and isolation help prevent the spread of infectious diseases, but they are different. Quarantine is for well people who might have been exposed to see if they become sick. Isolation is for sick people to keep them from infecting healthy people. So the suggestion for self-isolation means that sick people should stay away from healthy people.
Cueball's response to this advice is that he's "been practicing for this moment [his] whole life". xkcd frequently refers to social awkwardness, introversion, and difficulty with interpersonal interactions. Cueball (likely representing Randall himself) appears to find spending time in public and with large groups trying. It's implied that he prefers to spend time alone (or possibly with small groups of family and close friends) rather than going out. The joke is that this tendency is often seen as unhealthy and alienating, but in the case of a pandemic, actually becomes quite valuable. Cueball seems to take an odd sort of pride in the fact that he's skilled at remaining alone and uninfected, while more social people would be in danger.
The comic image is a link to one tweet in a thread of tweets about COVID-19 by @kakape , a science journalist according to their Twitter bio, which says "Social distancing may mean staying further apart from each other physically in coming weeks. We should compensate by caring even more about each other than usually, because we are, of course, all in this together." ( beginning of thread ).
In the title text, Cueball continues to be proud of his introversion, claiming that he has been "practicing social distancing" for much of his life.
[Cueball sits in an armchair watching television. A zigzag line from the TV indicates that the text is a voice from the TV.] Voice from television: Experts are saying people may need to "self-isolate" to combat the virus.
[A slim beat panel with Cueball sitting silent in the armchair.]
[Zoomed in on Cueball in the armchair. A starburst on the right border indicates the voice from an off-panel person.] Cueball: ... I've been practicing for this moment my whole life. Off-panel voice: I don't think that's— Cueball: Quick, make plans and watch how fast I cancel!


Business Greetings

Explanation:
This comic is the third comic in a row in a series of comics about the COVID-19 pandemic . With this comic also on that topic, all comics of that week were about the pandemic. This continued for many more weeks.
As a reaction to the COVID-19 pandemic, people are refraining from personal contact. This leads to changes with customs in the workplace, such as shaking hands at the beginning of a meeting.
The comic shows Beret Guy addressing his employees at his eccentric company ( Ponytail , Hairy and Hairbun , see also 1997: Business Update ). He states that although they should not overreact to the coronavirus, they should at least stop their custom of beginning meetings by "licking each others' eyeballs". Virus or not, it is not common for people to lick anyone's eyeballs at meetings, [ citation needed ] but it could be an extreme stretch of intimate behavior to make an analogy to some cultures' norm of kissing acquaintances in greeting.
Humorously, his employees state that they will miss this human contact, but that they at least understand.
Contact between saliva and eyes are a very common way to spread the disease. However, this usually occurs from one infected person sneezing and airborne particles randomly coming in contact with an uninfected bystander's eye, or people touching their own faces and eyes after having touched an infected surface, not by applying the saliva directly to a person's eyeball by means of another person's tongue. Also, most people's eyelids instinctually close when they see an object, including someone else's tongue, about to hit them in order to protect the eyeballs, so actually licking each others' eyeballs, as opposed to merely each others' eye lids , would be very difficult for most people, but Beret Guy being able to do this would not be very surprising considering his other abilities, such as being immune to his head being impaled.
The title text refers to an actual business custom (exchanging business cards ), but one which is absurdly altered to promote the spread of disease by touching cards and hands to faces. It is not clear whether this is safer or more dangerous than Beret Guy's previous practice of eating business cards, see 1032: Networking .
[Beret Guy is standing to the left addressing Ponytail, Hairy and Hairbun sitting in office chairs at a table. Hairbun is at the end of the table. All three have one arm on the table.] Beret Guy: I don't think we should overreact to the coronavirus, Beret Guy: But it might be time to put an end to the custom of starting business meetings by everyone licking each others' eyeballs. Hairy: I'll miss the human contact, but that's fair. Hairbun: Gotta change with the times.


Scientific Briefing

Explanation:
Things are not good, and are going to be bad soon.  The only way for things to not be bad is for someone to do something about it. Megan and Cueball are presenting these things to White Hat , evidently hoping to encourage him to do something about things, but he instead chooses to wait for things to become bad, to which Megan replies that the conversation itself indicates they have become bad.
Megan's final remark — "Based on this conversation, it already has [become bad]" — is an instance of recursion , and suggests that the unnamed subject of the graph may be something whose worsening is demonstrated by the way the discussion of the graph has gone.  The subject of the graph could, therefore, be the phenomenon of people not acting on things that are worsening until they actually become bad, as White Hat proposes to do.  At the time this comic came out, the outbreak of COVID-19 was on the rise and about to be declared a pandemic, with widespread perception the US federal government had failed to act before the outbreak became a crisis.  The first of the COVID-19 comics, 2275: Coronavirus Name , explicitly showed people not dealing with one problem while they concentrate on another (though in that case they were dealing with COVID-19 while neglecting an invading giant spider).
The recursive subject of the graph could also be the deterioration of data analysis into such abstract terms that it no longer depends on the content of the topic supposedly being analyzed.  Or, Megan's final remark could be an ironic commentary on the situation without actually referring to the topic of the graph.  The ambiguity of Megan's remark may be the point of the humor, as it compounds the absurd ambiguity of the entire discussion.
If the graph isn't about the recursive topic of the discussion, what might it be about?  At the moment of release, an obvious possible thing on its way to becoming bad was the number of cases of infection in the COVID-19 pandemic.  There were a series of comics about COVID-19, including the three comics immediately before and the four immediately after this one.  The graph shows a steadily rising line, but with a slight zigzag in it, which could be an intentional similarity to the Keeling Curve .
The graph could also be about most anything else, because, as the title text remarks, it applies to "like half of" any things considered.  While it's hard to say whether precisely 50% of all things are getting bad (or good), in a more general sense all line graphs would trend at least slightly either up or down.  This binary 'either good or bad' finding may lead one to conclude that "like half" of all graphs show something getting bad (or else good).  If not everyone agrees on what is "good" or "bad" on some issue, that same issue might even be viewed as going either from good to bad or from bad to good, providing two different graphs for each such issue with 50% of them broadly matching the comic.
To whatever extent this comic is related to COVID-19 — which it does not after all explicitly mention, but, at least, COVID-19 exemplifies the problem of waiting to act until things reach a crisis — it would be the fourth comic in a row in a series of comics related to the COVID-19 pandemic .
[Megan and Cueball are showing a graph on a projected screen.  The graph is labeled "Things", with "Time" advancing to the right on the x -axis.  The level of "Things" has been rising over time to a point labeled "Now".  The current level of "Things" is above a level labeled "Good", and about as far below a level labeled "Bad".  Megan is pointing to the line of "Things" with a pointer stick, while Cueball is pointing up to the "Bad" level with a pointer stick.]
Megan: Here's the situation: Megan: This line is here. Cueball: But it's going up toward here .
[White Hat enters the scene.  His hand is on his chin.  Cueball is no longer holding a pointer stick.]
White Hat: So things will be bad? Megan: Unless someone does something to stop it. White Hat: Will anyone do that? Megan: ...We don't know. Megan: That's why we're showing you this.
[A narrow panel focusing only on Megan and Cueball.]
White Hat (off-panel, left): So you don't know, White Hat: And the graph says things are not bad. Cueball: But if no one acts, they'll become bad.
[White Hat is back inside the frame.  He is gesturing to Megan and Cueball with his palm up.]
White Hat: Well, please let me know if that happens! Megan: Based on this conversation, it already has.


Symptoms

Explanation:
This comic is the fifth comic in a row in a series of comics about the COVID-19 pandemic .
The comic states that the symptoms of a disease are shortness of breath , fever , fatigue and dry cough . These are the top 3 and 5th most common symptoms reported for COVID-19. This is thus the fifth comic in a row about this disease, released on the day that the World Health Organization declared the COVID-19 outbreak a pandemic .
Looking these symptoms up on his phone, Cueball reads them to Megan who expresses relief.  The experiences of hers she claims as normal are so extremely opposite to the symptoms of the disease, that getting it might even be a boon rather than a harm. If a person has powerful lungs, shortness of breath wouldn't be very noticeable. She references icy skin, normally not a fever symptom, although heavy sweating caused by fever can lower temperature. She describes having frenzied energy, the opposite of fatigue.
The last symptom is an "incredibly wet cough", and although that is the opposite of a dry cough, it still sounds quite bad. The description she gives opposes COVID-19, but may be indicative of something else.
The focus on how symptoms play out differently for people with different normal experiences distantly touches on, but deftly evades, the harsh reality that people who, unlike the comic's characters, already have severe respiratory issues, may die in large quantities unless our response to the virus improves.  This is because the impact of a disease relates to how bad its symptoms are for the carriers.
Megan's optimistic reaction is ironic, considering these could be symptoms of a whole host of medical situations, including any kind of flu.
The title text expands on this joke. Cueball reads up on the side effects from some medicine. Here again they don't have the common side effects of the medicine but the exact opposite, so they think they must be fine, even though those "anti-symptoms" are themselves cause for concern.
It also reflects on the whole concept of symptom/side effect warnings themselves as often people have no good frame of reference for when a particular symptom is actually abnormal.  It is often easy for one to believe they match some or all of a list of symptoms because for someone to be absolutely sure they do not have a specific symptom, they would need an almost comic level of "normality".
The medicine is supposed to make the user:
Having a heavy head is not a good sign, even though the opposite is also not good. Dry mouth can be annoying but her condition sounds dangerous. And although blurred vision is a bad thing, it is impossible for a human eye to follow the 12-80 beats a second of a hummingbird; this suggests that Megan might be hallucinating, which is arguably even worse.
Much later in 2580: Rest and Fluids , the joke is again on symptoms or rather getting them again. The pandemic was still going almost two years later.
[Cueball and Megan stand facing each other, with Cueball looking down at his smartphone held up in one hand.] Cueball: It says here common symptoms include shortness of breath, fever, fatigue, and a dry cough. Megan: That's reassuring to me, a person with powerful lungs, icy skin, frenzied energy, and an incredibly wet cough.


2010 and 2020

Explanation:
This comic is the sixth comic in a row in a series of comics about the COVID-19 pandemic .
White Hat , who lives in 2010, and Cueball , who lives in 2020, are in contact with each other via some kind of time travel. White Hat wants to learn about life in 2020 and is particularly interested in bitcoin , a decentralized cryptocurrency which was released in 2009, and whether it had become an acceptable currency. Cueball answers that bitcoin still exists, and that he just bought a bottle of hand sanitizer for the price of one bitcoin. White Hat probably assumes that bitcoin is a widely accepted currency worth a few dollars, and thinks that the situation is "normal". (In April 2010, one bitcoin was worth about 14 cents.)
At the time of this comic, the COVID-19 is spreading around the world, causing thousands of people to die (although relatively few compared to the number of people that have gotten better) and billions to panic. This increased the demand for hygiene products, including hand sanitizers, and therefore their price has increased. It also triggered a panic on financial markets, including severe devaluation of the infamously volatile bitcoin. Despite the crash, one bitcoin was still worth about $5,400 on the day this strip was published, not a few dollars. Therefore, buying a hand sanitizer for one bitcoin is not as normal as White Hat assumes.
The price of hand sanitizer has not reached the price of a bitcoin (yet), although some people on sites such as Amazon.com are attempting to sell it for ludicrous amounts and there are attempts by Amazon, eBay, and other selling platforms, as well as potential legislation, aimed at curtailing such price gouging .
The title text claims that, in 2030, bitcoin will again be worth about one dollar, but many houses will also be worth only one dollar due to the difficulty inherent in containing "holo-banshees" in the attic.  What a holo-banshee is is not explained, but one can guess as to what it might mean.  "Holo" is generally short for hologram and typically denotes some kind of 3D looking digital visual form, and a " banshee " is a mythological wailing creature or spirit.  So even if not a physical object, constant shrieking would be undesirable. [ citation needed ]
The "nominal fee" mentioned by the 2030 time traveler is known in legal parlance as a "peppercorn". In reality, such a practice has been quite common for several decades (though not for something on the scale of a house); legal processes state that both sides must give something in order for a contract to exist, and a minimal peppercorn payment to secure a contract is preferable to the legal hoops that must be jumped through in order to lawfully give something away for nothing.
[White Hat and Cueball are walking to the right of the panel. There is a gray outline around Cueball, indicating he is from the future] White Hat: What are things like ten years from now in 2020? White Hat: We have this new "bitcoin" thing — does it ever catch on and become normal?
[A frameless panel, with White Hat and Cueball still walking to the right.] Cueball: It's still around. I just bought a bottle of hand sanitizer for one bitcoin.
[A regular panel, with them continuing to walk] White Hat: Cool, that sounds pretty normal. Cueball: Well, here's the thing...


Coronavirus Research

Explanation:
This comic is the seventh comic in a row in a series of comics about the COVID-19 pandemic .
Megan , disheveled and exhausted, has been researching COVID-19 nonstop and is now reporting her findings to Cueball . She claims to have read all available literature on the subject, but the best she can come up with is an extremely basic fact about viruses —namely that they infect cells and this is bad and should be prevented, which Cueball and just about everybody else already knew. She enthusiastically replies that she now knows this with error bars , which are graphical representations of the variability of data and are used on graphs to indicate the error or uncertainty in a reported measurement. Perhaps because of her sleep deprivation, she is unable to process the information that she has read, or is unable to properly phrase it in words. This is not the first time that Megan has exhaustively researched a topic to the detriment of her own health, see 1708: Dehydration .
In the title text, she has a hunch that staying awake long enough to read 500 scientific papers is probably not a good idea, but she hasn't found a study that specifically confirms that. She intends to further compound her exhaustion by continuing to do research rather than just getting some much-needed sleep. Assuming that Megan averages half an hour to find and read each paper, she has been continuously reading for 10.4 days, which is approaching the world record for not sleeping. In 1964, Randy Gardner , a student in San Diego, California set the then-world record of 11 days and 25 minutes (264.4 hours) without sleeping.
[A very disheveled Megan, hair in disorder, walks up to Cueball.] Megan: Hi. Cueball: Hello. You look...fine.
[In a frame-less panel Megan has stopped next to Cueball.] Megan: I have now read virtually every available scientific paper on COVID-19. Cueball: Cool, what'd you learn?
[Megan has raised her palms towards Cueball.] Megan: Well it seems this virus wants to get inside your cells. Cueball: Mhmm...
[Megan raises her left arm, with her index finger in the air in front of Cueball's face.] Megan: But it's a trap! You shouldn't let it. Cueball: I think we knew that. Megan: But now I know it with error bars!


Coronavirus Worries

Explanation:
This comic is the eighth comic in a row in a series of comics about the COVID-19 pandemic .
Randall has created a scatter plot graph showing "more common" worries versus the "more healthy" worries. Presumably, "more healthy" refers to more important things to worry about concerning the COVID-19 pandemic. From this graph, Randall notes that the "more healthy" concerns are not necessarily the ones that are the most common.
On the left side of the graph, signifying "less common" worries/concerns are concerns relating to the drinking of water, and resting. Drinking water (staying hydrated) and getting enough sleep each night are important ways to fight off disease, and they're things that almost everyone can take direct action on, so this is marked as one of the most healthy things to worry about.  In 2281: Coronavirus Research , Megan shows signs that she (like many) has not been taking care to get enough sleep.  However, not drinking enough water and not sleeping enough are not likely to cause coronavirus specifically, so that particular worry is marked as one of the least healthy.
In the middle of the graph are "medium common" worries/concerns. The "most healthy" or vital concerns are being able to stay home and the ability for friends and family to stay home. Across much of the world, public gatherings have been discouraged, including requiring many workers to telecommute . This is following the principle of social distancing , to slow the spread of COVID-19. These are considered very healthy concerns to be having.
Below these two concerns is concerns about the government response, specifically if the government is "reacting wrong". Many world governments have been criticized for inadequate responses to the pandemic. However, even if the government's response (or lack of response) is incorrect, it is not something that most people can control directly, nor should it prevent people from taking care of the more healthy concerns about staying home and staying well-hydrated and well-rested, which is why this worry is marked as being only moderately healthy.  Even less important than the government response is worrying about the reactions of random people featured in news stories (who are most likely featured specifically because their behavior is extreme or aberrant) or Internet trolls or people who have different opinions to you in the story's comments section.
A more common concern listed is "whether you are getting enough work done". Telecommuting (working from home) may be less productive than working at the normal office, so Randall or others may be concerned about their work productivity.  For people working in industries that directly affect the health and well-being of others, such as medicine, this is a fair concern (and many of the event cancellations and other responses are intended to make their jobs easier), but in general, this is a much less healthy concern than staying home and well-rested.
The most common and least important concern according to Randall is "whether you have the virus just because you just coughed and last week you touched a doorknob". Though it is an important to be concerned about catching the coronavirus, simply coughing a few times or "touching a doorknob" are unlikely reasons to suspect having COVID-19. Most cases of COVID-19 do include a cough, and the disease can be latent for over a week before showing symptoms, but also include other symptoms, including fever and difficulty breathing.
The title text lists an uncommon, unimportant concern: the copyright status of a "coronavirus emoji" on Slack (a business instant messaging software). The Creative Commons license is a license allowing for fair use of published work (and presumably emojis)  that are otherwise copyrighted. Something that is in public domain has no copyright protection on it, and can be used freely. Presumably, this is a concern that only Randall has, making it uncommon. It is also relatively unimportant in the greater scheme of the COVID-19 pandemic.
[A scatter-plot, with 8 labeled dots. Both axis are labeled with text beneath the X-axis and to the left of the Y-axis. Arrows are pointing to the right from the X- axis and up from the Y-xis. The dots are scattered from left to right and top to bottom, but there are some grouping of the labels with two to the left, four in the middle and two to the right. But the dots they belong to are more scattered than this. Here below all labels are given, first for the axis, and then for each dot in approximately normal reading order from the left column to the right column:] Y-axis: More healthy X-axis: More common
[Top left]: Whether you're remembering to drink water and rest [Very bottom, near left]: Whether forgetting to drink water or rest will make you get the coronavirus [Very top, near right]: Whether you're able to stay home [Top leaning, right]: Whether your friends and family are able to stay home [Middle, leaning right]: Whether your government is reacting wrong [Very bottom center]: Whether random people in a news story are reacting wrong [Toward bottom right]: Whether you're getting enough work done [Very bottom right]: Whether you have the virus because you just coughed and last week you touched a doorknob


Exa-Exabyte

Explanation:
This comic is arguably the ninth comic in a series of comics related to the COVID-19 pandemic . This comic does not mention the disease but it does mention biology.
This is a comic about the difficulty of picturing or understanding large numbers. As mentioned in the comic, an exabyte is 10 18 bytes, while an "exa-exabyte"—not a common word, but one that abuses the principles of metric prefixes —would be 10 36 bytes. 10 36 is properly given the name undecillion (in short scale, and sextillion in long scale).
According to a 2015 article by The New York Times , researchers estimate that there are about 5 * 10 37 DNA base pairs on Earth (50 trillion trillion trillion). So Miss Lenhart 's claim of 10 exa-exabytes—1 * 10 37 bytes is a reasonable approximation ( Fermi estimation ).  (The estimate was 5 plus or minus 4 * 10 37 .  There are 4 possible base pairs, or 2 bits per pair, a byte is 8 bits.)
These numbers are larger than most people can imagine. Even much smaller numbers such as a billion (10 9 ) or a trillion (10 12 ) are hard to imagine. For instance:
Wikipedia has an article on the exabyte and one on large numbers which describes various things close to 10 18 .
Cueball expresses his difficulty in visualizing a number even as large as one exabyte (10 18 bytes).
Megan trivializes the problem away by describing an exabyte as 10 apples, with "18 smaller apples, floating next to them and a little above", representing the notation 10 18 using apples for digits. This is entirely unhelpful, as using apples in a base-1 enumeration offers no obvious advantages over base-10 in understanding exponents; Megan's bad advice & Cueball's seemingly ready acceptance of it causes Miss Lenhart to yell out "No!" in frustration.
The title text further trivializes the problem of visualizing large numbers by suggesting that you can visualize 10 18 as a number by simply visualizing the similar-looking number of 10 13 with some extra lines drawn to turn the 3 into an 8. Changes in exponents can cause huge changes in the value shown, and this is no exception: Changing that 3 into an 8 changes the value by a factor of 100,000.
Randall has previously discussed the difficulty of large numbers in 2091: Million, Billion, Trillion , 1894: Real Estate , and 558: 1000 Times .
1605: DNA also discusses how "hard" biology is.
[Miss Lenhart is holding a pointer, and is pointing it towards a blackboard behind her, while she addresses her student Cueball who is sitting on a chair at a desk to the left of her, holding his hands on his knees.] Miss Lenhart: Biology is hard because there's so much of it. Earth hosts about 10 exa-exabytes worth of DNA.
[In a frame-less panel, the panel has panned to the left and is now showing Miss Lenhart holding the pointer to her side, but without the blackboard. In front of her is now both Cueball and Megan sitting at their desks. Cueball has taken one hand on to the table. Megan has both hands folded on the table in front of her.] Cueball: What's an exa-exabyte? Miss Lenhart: It's 10 36 bytes. Cueball: How do I picture that? Miss Lenhart: Imagine you had an exabyte of data, but each byte contained an exabyte of data.
[Zoom in on Cueball's head. A starburst to the right indicates Miss Lenhart's voice from off-panel.] Cueball: I can't even picture what an exabyte is. Miss Lenhart (off-panel): It's 10 18 bytes. Cueball: But how do I picture 10 18 ?
[Zoomed out to showing Megan, Cueball, and Miss Lenhart along with the blackboard. Megan has raised a hand palm up. Cueball is looking back at her over his shoulders.  Miss Lenhart is forming a closed first with her empty hand, the one without the pointer.] Megan: Imagine you had 10 apples. Megan: Now imagine 18 smaller apples, floating next to them and a little above. Cueball: Cool, got it. Miss Lenhart: No!
In 1519: Venus , release date May 1, 2015, Miss Lenhart indicated that she was retiring as a primary or secondary school teacher in a month. Here we see Megan and Cueball, both adults, sitting in a classroom setting with Miss Lenhart providing instruction.  A reasonable assumption is that Miss Lenhart has taken some form of adult education job during her retirement.  For example, in the United States it is common for community colleges to use low paid adjunct professors who either have a day job or another source of income such as a teacher's pension.
There is also a hint of irony in her having to now put up with the same type of blatantly incorrect explanations that she herself was freely giving out just prior to her retirement.


Sabotage

Explanation:
This comic is the tenth comic in a row in a series of comics about the COVID-19 pandemic .
In the wake of the COVID-19, the advice from many professionals in the United States is to avoid public gatherings to slow the spread of the disease and "flatten the curve".
In this comic, some group of people (we're not told who) are planning a public event, which is very much contrary to the widespread professional advice, and is said to put everyone at risk by accelerating the spread of the disease in the general population.  In an effort to sabotage this event by deterring people from attending, Cueball applies reverse psychology, pretending to be enthusiastically planning various activities at the gathering that most people would go out of their way to avoid:  a wild skunk petting zoo, which would most likely result in everyone getting heavily sprayed with violently foul-smelling skunk scent that wild skunks use to drive away predators; and karaoke featuring the song " Baby Shark ", which is a song for small children that is generally considered annoying to adults, made even more direly annoying in this case by being spoken rather than sung.
In the title text, Cueball has stepped up his game from merely threatening to spoil everyone's fun to making them fear that they might get infected.  He claims to have attended the "World Handshake Championships", which presumably would involve shaking hands with as many people as possible; this would facilitate the spread of diseases such as COVID-19.  He furthermore claims to have traveled home from the championship via a cruise ship, which may also cause concern because cruise ships are known for their densely populated environments and lack of extensive medical facilities making prevention and treatment of infections very difficult or impossible. Cruise ships have been a recent topic of interest in relation to SARS CoV-2 due to many people being stranded at sea with infected patients because of COVID-19 pandemic on board.
[Cueball is seated at a desk, typing on a laptop. The top half of the image is the text he is typing in a reply message:] "I see you're still getting together today! I'll be there, doing my spoken-word Baby Shark karaoke all evening. We'll also be setting up a petting zoo for the kids. We've spent all week trapping wild skunks!" [Below the text is a white-on-green "reply" button.]
[Caption below the panel:] In the coronavirus era, desperate times call for desperate measures.


Recurring Nightmare

Explanation:
This comic is the eleventh comic in a row in a series of comics about the COVID-19 pandemic .
Megan states to Cueball that she keeps having the same nightmare. As she begins to explain that in her dream she shows up at school and panics as she realizes something, Cueball interrupts her to suggest she has turned up at school naked. But instead, Megan says that she finds herself in a crowded room at school.
It is an allegedly frequent dream-trope to be in a situation of otherwise polite company and discover oneself naked in the midst of the crowd. This can be added to something such as a general " forgotten to prepare for the exam you're sitting " to build upon various levels of worst-case scenario anxieties amongst your peers, parents or other persons who will judge you badly for your faux pas .
In light of the current COVID-19 pandemic, Megan is obviously dreaming up her problem of being in a crowd (at school), as most schools have stopped holding in-person classes (at the time of this comic, most schools in many countries had switched to online instruction or have completely closed due to the pandemic).
Social distancing has been widely practiced around the world as a way to slow the spread of the disease. In the title text, Megan finds relief in dreaming that she's naked, as her nudity, perhaps similar to the actual real-life 'health tip' of eating excessive garlic, has the unintentional but beneficial effect of having crowd members back away from her personal space out of shock and/or mutual embarrassment.  This may somewhat mitigate the viral transmission by droplets from coughs, although to be more protected, Megan should dream that she is at least wearing a face mask, or that she is going to thoroughly wash her hands as soon as possible, in case she has touched any contaminated surfaces.
Nightmares about school were also the topic of 557: Students , specifically stating that people have dreams about school, even when already having graduated.
[Megan, standing next to Cueball, is gesturing with her arms wide.] Megan: I keep having nightmares that I show up at school, and then suddenly panic as I realize– Cueball: –that you're naked? Megan: That I'm in a crowded room!


6-Foot Zone

Explanation:
This comic is the 12th comic in a row in a series of comics about the COVID-19 pandemic .
This comic is about social distancing , a common practice to prevent the spread of the COVID-19. It has been suggested to maintain 6 feet (i.e. 1.8288 m - in e.g. France and Britain the suggested distance is 2 m) of distance between yourself and other people, to prevent the transmission of respiratory droplets from you to others (or vice versa).
Randall takes this 6 feet of distance, and does calculations of the "area" of distancing, "border", population density, and "real estate value". He finally culminates in determining the number of horses that could also fit in the space.
Randall's border length and approximate area calculations are based on a zone with an outside radius of approximately 6.8 feet or 82 inches (2.07 m), meaning that the person has a radius of approximately 0.8 feet (9.6 in, 0.24 m). That is, 2π(6.8ft) = 42.7 ft and π(6.8ft) 2 = 145.3 ft 2 .
There are two different population densities that can be calculated. The one used by Randall in the comic is the population density of the exclusion zone itself, i.e. just the reciprocal of its area. This is π -1 (6.8 ft) -2 = 190,000 mi -2 . A different density is the density of a crowd in which everyone obeys the distancing rules. That would result in 0.9069(π -1 )(3.8ft) -2 = 560,000 mi -2 population density. When people stand 6ft apart from each other, their exclusion zones are overlapping; instead we can use smaller circles  with 3.8 ft radius that are not overlapping. 0.9069 is the packing density of circles in the plane.
For comparison, only 21 countries have a population density >1000 mi -2 , but there are a few cities with a population density on the same order of magnitude (~100,000 mi -2 ).
The USFS Equestrian Design Guidebook is (of course) a real thing, and it discusses the dimensions of the design horse
The title text is a pun using the alternate definition of foot by switching the naming from 6-foot zone, where foot is used as a unit of distance, to 34-foot zone, where the number represents the total number of feet inside the circle, including the horses’ feet, assuming the human is endowed with the standard two feet and each horse has the standard four feet apiece.
[Caption:] Guide to the 6' Social Distancing Zone
[Profile image of Megan with 6 foot distance measurements on both sides. Also indicated is the width of the full "6' zone", which consists of 6' to her right, her width, and 6' to her left. Her width is not explicitly indicated.]
[Overhead image of a person within a slightly elliptical outline at a distance of 6 feet in all directions. The "width" of the person pushes the ellipse longer in one dimension. The ellipse is again labeled "6' zone".]
[Statistics:] Approx. area: 145 ft 2 Border length: 43 ft Population density: 190,000 people/mile 2 Value at NYC real estate price/ft 2 : $195,000 Maximum number of horses that could fit inside it with you, estimated using the dimensions in the US Forest Service Equestrian Design Handbook : 8
[This last statistic is illustrated with a second overhead image, showing 8 horses, mosaicked together a little like an M.C. Escher tesselation, filling the entire 6' zone along with the person.]


Pathogen Resistance

Explanation:
This comic is the 13th comic in a row in a series of comics related to the COVID-19 pandemic .
Rather than expressing humanity's fears and pessimism about the pandemic, this strip anthropomorphizes some of the pathogens which afflict humanity and presents their fears and pessimism about possibly going extinct.  This serves as a roundabout way of expressing hope and wonder at the ingenuity and tenacity of humans in the face of diseases past (with water sanitation, mosquito netting, and condoms) and present (with the power of social distancing and Gloria Gaynor 's hit song I Will Survive ). Gaynor recorded a video of herself washing her hands for 20 seconds (the recommended length of time to wash hands for optimal cleanliness) to the background of her hit song.
The three pathogens presented are a virus (a bacteriophage ), a small colony of a coccus -shaped bacterium (such as Streptococcus ), and a protozoon (a caricature of a ciliate ).  Bacteriophages do not infect human cells (as the name suggests, they only infect bacteria), and have been studied for use as " phage therapy " for humans, especially in dealing with antibiotic-resistant bacterial infections (which is usually what people mean when they talk about "resistance" in the context of pathogens); however, they are iconic, instantly-recognizable viruses, and some have been found to collude with bacteria in forming certain antibiotic-resistant biofilms . Only one kind of ciliate is known to cause human disease; however, ciliates are iconic for protozoa just as bacteriophages are for viruses (see, for example, Gary Larson's now-venerable The Far Side cartoons). The ciliate may be a 'stand-in' for protozoa that cause widespread and dangerous human diseases, such as malaria . The drawing is wildly out of scale; a protozoon is larger than a bacterium, which in turn is much larger than a virus.
"The scariest thing in the universe" to these microbes is the human immune system, represented in the second panel and later by antibodies (Y-shaped drawings) and anthropomorphized macrophages (actual macrophages do not have glaring angry eyes [ citation needed ] ). When a T cell encounters an unfamiliar molecule in the body, such as the surface proteins of SARS-CoV-2, it will search for a B cell that produces a matching antibody.  If and when it finds such a B cell, it will command the B cell to rapidly multiply and mass-produce antibodies.  Those antibodies will then bind to any antigens they contact, which may impede the antigen (as shown by the tagged protozoon in panel 2 lagging behind its siblings) and will definitely mark them for destruction by macrophages, which engulf ("HUUGGG") and digest antibody-tagged objects they encounter.  T cells can also be described as hugging cells , but a hug from a T cell is used to activate other processes, while a hug from a macrophage is a precursor to digestion.  White blood cells are quite persistent once they have detected an antigen, even chasing them over many cell lengths in what must be a terrifying experience for the antigen being chased.
The comic humorously considers pasta as an essential part of humans' fight against coronavirus. Pasta is an example of a dried food that can last a long time, if the orders to stay indoors continue, and was one of many products bought in mass quantities by shoppers "panic-buying" at the onset of lockdowns. Pasta is a popular dish in Italy, which is experiencing particular difficulties with COVID-19, but not every culture consumes or likes pasta. In addition, the Gaynor vid was initially shared via soundpasta.com among other services, and "pasta" is sometimes used to refer to sharing over the internet via cut-and-paste.
The colony of cocci protests that it shouldn't be possible for humans to evolve "pathogen resistance" in the short period of months since the breakout of COVID-19, when humans require over a decade to reach sexual maturity, and in modern times often wait at least two decades before having children.  Humans develop immunity to some diseases after being infected, as some B cells become memory cells and are stored for quick re-activation in the case of a later infection, but this is not very effective against viruses which mutate rapidly, such as influenza and the common cold (which is sometimes caused by coronaviruses, although not SARS-CoV-2).  Bacteria and viruses, on the other hand, reproduce in a matter of minutes, so that there may be hundreds of generations per day (comparable to the number of generations that have passed for humanity since the beginnings of agriculture), each of which presents opportunities to evolve new antigens that are not recognized by any antibodies present in the body or to evolve resistance to whatever antibiotic drugs the host might be using.  However, as the bacteriophage explains, humans generally do not become resistant against pathogens by genetic drift (although there are researchers who are seeking to identify genes that encode resistances to various diseases and then propagate them to other humans through gene editing, as in the He Jiankui affair ).  Instead, humans "evolve" pathogen resistance through behavioral changes.  The behaviors presented in this comic strip include:
These behaviors do not come from our genomes, passed along through reproduction, but from our brains, passed along by communication.  Some of the language of epidemiology is also used in discussion of communication, most notably "going viral" -- in this case, information is going viral to prevent viruses from going viral.
The title text reverts to the point of view of humans and references a famous line from the graphic novel Watchmen , where the vigilante Rorschach , whilst in prison and surrounded by enemies who want to kill him, proclaims: "I'm not locked up in here with YOU. You're locked up in here with ME."  This presents an alternate perspective on quarantine and isolation that some may find more bearable: rather than passively hiding indoors in fear of the virus, we are taking action to fragment the virus population so that our immune systems (and medical intervention, in more serious cases) can defeat it in detail .
[A small colony of coccus bacteria, a bacteriophage, and a protozoon, with an eye, are floating together.] Bacteriophage: I'm worried about humans developing resistance to us. Bacteriophage: Using pasta.
[In a half height panel we see two macrophages, each with an eye, and lots of Y-shaped antibodies chasing three protozoa, also with one eye each. One protozoon is already covered in antibodies and seems to have fallen over. Above the panel is the text that the bacteriophage is narrating.] Bacteriophage (narrating): The human immune system is a nightmare. Bacteriophage (narrating): It's the worst. Bacteriophage (narrating): It's the scariest thing in the universe. Macrophage: Who wants a Huuggg Antibody-covered protozoon: Nooo!
[Close-up on bacteriophage] Bacteriophage: We can only survive by staying ahead of it.  Keep jumping from person to person, keep mutating and evolving. Bacteriophage: But now humans are adapting too fast.
[Water pipes. A mosquito net with a bed under it. An unopened condom package.] Bacteriophage (narrating): We spread through their water. They built pipes. Bacteriophage (narrating): We used mosquitoes. They put out nets and poison everywhere. Bacteriophage (narrating): We spread through sex, and suddenly they all had these plastic things.
[Depictions of seven coronavirus with spikes, one very large, one large, two small and three tiny. They are above a picture of Hairbun and Cueball shaking hands, while exhaling a cloud and tiny droplets spraying all over from both their clouds from exhaling.] Bacteriophage (narrating): This time, we really thought we had them. Bacteriophage (narrating): One of us got good at transmission through everyday contact.
[A row of four sets of human lungs and their trachea is shown. The first set of lungs has just one black dot in the left and a few black dots in the right lung. The second has the bottom right lung covered in black, and the left lung has a bit black on either side and still some black dots in the middle. The third has most of each lung covered in black, except maybe a quarter of each lungs top. The fourth set of lungs are completely filled with black. Below them is a graph showing exponential growth with an X-axis with 17 equidistant ticks and to the right a Y-axis with eight equidistant ticks. This time the narrating is indicated to come from off-panel left with a speech line, and so are the two answers, coming from the off-panel right. It is like if the speakers are looking at this chart from off-panel.] Bacteriophage (off-panel left): It was great. We were tearing through lungs, spreading like wildfire. Voice (off-panel right): Hooray! Voice 2 (off-panel right): I hate lungs.
[Close-up of bacteriophage "head".] Bacteriophage: Then, all of a sudden, humans everywhere just... stopped . They stopped working, stopped seeing friends.
[Megan is sitting on a couch with a remote control in her hand, watching a flat screen TV. Cueball is at a sink with a mirror, washing his hands under hot water indicated by heat lines coming up from his hands. They are facing away from each other. Again speech is come from off-panel left and right with speech lines] Voice (off-panel left): What are they doing ? Bacteriophage (off-panel right): Nothing! Bacteriophage (off-panel right): They're just sitting there in their houses washing their hands.
[Cueball stands in an otherwise empty room He is surrounded by falling droplets, many of which are now lying on the floor around his feet. Among the droplets is a coronavirus that shouts out.] Bacteriophage (narrating): Suddenly humans became dead ends. We tried to jump from one to the next, but there's no one to jump to. Coronavirus: Help! Bacteriophage (narrating): We can't escape.
[Three large Coronaviruses and several smaller ones are encroached on by at least four macrophages, one showing a large eye, surrounding them as well as streams of Y-shaped antibodies mowing in towards the viruses. A rectangular panel at the top, is placed over the top edge of the panel. The narrating text is inside this panel:] Bacteriophage (narrating): We're trapped in there with those ghastly immune systems. Antibodies: It's huug tiiiiime Macrophage top left: Come here for a huuug Macrophage bottom left: Huuuuugs
[A slim panel, with text above and below the panel with narration. In the panel there are two larger coronaviruses covered in antibodies and attacked directly by macrophages. Smaller coronavirus are shown covered in antibodies as well. Some of the macrophages are actively devouring viruses. While others already contain broken-down remnants of a coronavirus. Most of the macrophages has an eye.] Bacteriophage (narrating): Even if we win a fight, there's nowhere to go. Macrophage a the top: Huuuuuuuggss Macrophage at the bottom: Huuugs Bacteriophage (narrating): By staying inside, humans have become resistant.
[Back to the discussion between the coccus, the bacteriophage and the protozoon with eye.] Coccus bacteria: How could they evolve that fast? Humans take decades to reproduce! Bacteriophage: It's not evolution. It's something with their brains. Protozoon: I wondered what those were for!
[Bacteriophage pointing with a leg to Cueball and Megan who are looking at their phones; Megan and Cueball are then walking to the right; Megan and Cueball are shown at separate sinks with mirrors washing their hands.] Bacteriophage: Humans started looking at their phones, talking, writing words, and making signs. A human named "Gloria Gaynor" filmed herself singing at her bathroom sink. Bacteriophage: And then they bought lots of pasta. Bacteriophage: Then, around the world, they all went home and started washing their hands.
[Bacteriophage and protozoon with eye.] Bacteriophage: They saw what we were doing and changed their behavior to stop us. Protozoon: Brains are the worst .
[Coccus, bacteriophage and protozoon with eye.] Coccus bacteria: It's not over, right? They can't sustain this. They must be bored and tired. Coccus bacteria: Will they give up? Bacteriophage: I don't know. They seem determined to protect each other.
[Coccus, bacteriophage and protozoon with eye.] Bacteriophage: And Bacteriophage: They have a lot of pasta.


Collector's Edition

Explanation:
This was the tenth April fools' comic released by Randall . The previous fools comic was 2131: Emojidome from Monday April 1, 2019. The next became 2445: Checkbox released on Thursday April 1, 2021.
It is a large image, of which only part is visible, but can be dragged around. This space acts as a shared virtual sandbox where viewers can interact.  "Items" (small, often humorous images) could be collected from other comics and then placed in this image by viewers. The collection then updated for all viewers in real-time. Multiples of the same item are often seen.
There is a "backpack" at the bottom, similar to backpacks in video games containing items collected by the player. As hinted by the title text, items could be found by visiting different XKCD comics/pages. Randomly, some pages would have a treasure chest which contained the sticker related to the page. The hint would refer to the page which currently had a chest.
The sticker images can be seen at https://xkcd.com/2288/collectors/static/loot/loot_ XXX .png, where XXX is a number from 001-253. Additionally, some images can be found at custom URLs, for example the periodic elements can be found at https://xkcd.com/2288/collectors/static/loot/element- XX .png, where XX is the element, and text loot at https://xkcd.com/2288/collectors/static/loot/loot-words- X .png, where X is the sentence.
As of April 5 2020, chests are no longer dropped.
Click “Expand” to see the full image.
[Cueball stands to the left of a vibrating box.] [The words "Collector's Edition" are written above him and boxed.]


Scenario 4

Explanation:
Although not directly mentioned, this comic is probably the 14th comic in a row (not counting the April Fools' comic ) in a series of comics related to the COVID-19 pandemic .
In 2278: Scientific Briefing , Megan and Cueball were briefing White Hat on things that were getting bad, hoping to convince him to do something about them.  He chose to wait until things actually got bad.  Evidently, that has happened, and now Megan and Cueball are delivering another briefing on just how much "Bad Stuff" there might be, according to their models.
In the context of the information (and misinformation) explosion associated with the COVID-19 pandemic (ongoing at the time that this comic was published), many graphs have been shown highlighting the prevalence of the disease - the number of cases at any one time and place, and the change in the number of cases over time. That being said, the graphs shown could easily apply to any number of scenarios where an upward trend is bad.
Several of these graphs have attempted to predict the future, using statistical tools ("models") to process existing data and generate a forecast. Inputs to the model(s) may include different assessments of, for example, the number of COVID-19 cases that have been recorded. Four scenarios are presented here, presumably showing what a particular model (probably only one despite the reference to "new modelS" in the comic) forecasts given different, unspecified, inputs.
Megan and Cueball present four scenarios, only three of which are possible.
[Megan and Cueball are standing in front of a large graph, with "Time" along the horizontal axis and "Bad Stuff" along the vertical axis. The curve on the graph shows a generally shallow upward slope.] Megan: Our new models outline a few possible scenarios. Cueball: #1 is the best scenario.
[The graph now shows a much steeper curve, before flattening out far in the future, similar to a logistic curve.] Megan: Scenario 2 is not so great.
[The graph now climbs quite quickly, approximating an exponential curve.] Cueball: Scenario 3 would be pretty bad.
[The graph starts curling up, like the exponential curve, but continues curving back, so that it no longer qualifies as a function, and may indicate time-travel to the past.] Megan: Then there is scenario 4. Megan: We think it's a graphing error. Cueball: If not, we definitely want to avoid it.


Homemade Masks

Explanation:
This comic is the 15th comic in a row (not counting the April Fools' comic ) in a series of comics related to the COVID-19 pandemic .
In this comic, Cueball wonders if Megan's homemade mask will be of any use, because he has seen many different points of view and is unsure which one is correct.  It is generally agreed that homemade masks will not block particles (including droplets which carry viruses) as effectively as officially-tested N95-class masks or surgical masks , and possibly confer no benefit at all; however, wearing a homemade mask may reduce contagiousness if the wearer is infected, by blocking droplets from being expelled.  It may also make the wearer less likely to touch their face (which may be a vector for catching COVID-19 from contaminated surfaces).  On the other hand, there are concerns that it may confer a false sense of security, leading to unsafe behaviors, and that the warm, moist environment produced by the wearer's breath may also harbor incoming viruses, which may later infect the wearer if the mask is not washed frequently.
Megan replies that she originally carried a sign warning people to keep their distance, but people needed to get close to her to read it, making it counterproductive.  The implication is that Megan's primary purpose in wearing the mask is to signal to other people that's she's concerned about spreading COVID-19, and remind them to keep their distance. Whether or not the mask has any direct benefits in blocking virus transmission, Megan apparently feels that the social impact of seeing someone in a face mask is likely to change behaviors, making transmission less likely.
The title text indicates an alternate method, where Megan could change the sign into a device for pushing people back in order to maintain distance.  Holding the sign out in front of her (instead of over her head) would also let people get close to the sign to read it, without getting in her face.
[Cueball stands at a distance from Megan, who is wearing a face mask] Cueball: Homemade mask, huh? You think they help? Cueball: I've read so many conflicting things.
[Flashback to when Megan was not wearing a mask but carrying a large sign, with Cueball and Ponytail approaching her from both sides. It is not possible to read what is on the sign. Masked Megan is pictured in an inset panel.] Megan (narrating): Well, what I was doing before was carrying around a big sign that said "There's a pandemic so please give me space because I don't want to get sick or make anyone else sick!"
[Same as first panel] Megan: The problem was, I had to write small to fit, so people kept walking closer to read it. Cueball: Oops. Megan: Yeah, the mask gets it across better.


New Sports System

Explanation:
This comic is the 16th comic in a row (not counting the April Fools' comic ) in a series of comics related to the COVID-19 pandemic .
As communities have been ordered to stay indoors to avoid spreading the virus, this has also affected sports leagues around the world, with many of them suspending their seasons, or cancelling them outright. (see this Wikipedia article for a full list of sports or sporting events impacted) Some leagues have instead promoted e-sports, such as the NBA holding an NBA 2K20 tournament between active NBA players .
Randall , in this comic, proposes an obviously bad "new sports system" of "virtual sports", in which players play with a virtual ball in separate arenas, and are guided by online viewers. This obviously proves to be challenging, as the ball is virtual but the players are not wearing any virtual reality or augmented reality headsets, and thus they do not know how to interact with it properly. Playing in separate arenas would solve the problem of spreading the virus, as the players do not have any direct interactions with each other.
This would be a similar system to Twitch Plays Pokémon , in which Twitch viewers "play" Pokémon video games in a crowdsourced manner.  There are also many games that are intentionally constructed so that some players must accomplish a goal they cannot see or with incomplete information, while they are guided by other players.  These include common team-building exercises (often involving blindfolds), and the bomb-disposal themed puzzle game Keep Talking and Nobody Explodes .
The NBA also is holding a similar idea, holding a Horse tournament among NBA and WNBA players , which works better than the version of basketball shown in this comic because players don't need to interact with the same ball.
In the title text, Randall claims that boxing and football (he does not specify gridiron football or association football) proved to be difficult, with pairs figure skating still possible as long as figures like elevations are removed, and professional wrestling being unaffected. Boxing and gridiron football would be impossible to play in these situations; on top of the difficulty of trying to play without knowing where the other players are located, these sports are predicated on contact. A boxer cannot get a knockout without being able to touch the other players, and football players cannot block or tackle even if they mime catching the ball. Association football, with less emphasis on contact, might still be playable, but would suffer at least from the same complications as basketball shown here. Pairs figure skating would be possible, excepting "throwing" moves or "lifts", as typically pairs figure skaters skate in unison, replicating the same moves.
Humorously, Randall claims that professional wrestling will be unaffected by his new system. This is in reference to the "open secret" that the matches have predetermined outcomes and are more "entertainment" than actual competition, with much of the 'forced' movement of one competitor being aided or even guided by the 'victim' rather than the 'aggressor' in semi-improvised feats of coordinated athleticism.
[Single wide frame representing a basketball court with a basketball hoop at each end.  There are seven players running around the court, with a virtual ball in the bottom right corner (indicated as a dashed circle).  Nine off-screen voices of "online viewers" are yelling instructions to the players.  A caption is below the frame running nearly the full width of the frame.]
Viewer One: No! Viewer Two: It's on the– Viewer Three: Look out! [A player with thick hair and a goatee is "air-shooting" into the left-hand basket.] Viewer Four: No! [A player with thick hair is running to the right.] Viewer Five: He's right there Viewer Five: Don’t run into– [A player with no hair is air-dribbling to the right.] Viewer Six: Go left! Viewer Seven: Left! Viewer Eight: Riiight! [A player with thick hair and a full beard is facing left and jumping, hands raised to intercept a ball.] [A player with no hair is facing left and crouching, reaching for a ball.] [A player with no hair is making an alley-oop motion towards the right-hand basket.] Viewer Nine: Stop dunking and find the ball! [The virtual ball is slowly moving right, unseen by the players.] [A player is hanging on the rim of the basket, making a dunking motion.]
Caption below the panel: No one liked my new sports system, in which each player is in a separate arena sharing a single virtual ball that they can't see while online viewers yell instructions, but it was fun to watch while it lasted.


Thermometer

Explanation:
This comic is arguably the 17th comic in a row (not counting the April Fools' comic ) in a series of comics related to the COVID-19 pandemic .
This comic expresses frustration at the multitude of temperature scales. Randall , as a former engineer, has strong opinions about units, as unit conversion is often a gripe for many engineers. (In a special preface in the UK edition of Randall's book What If , he mentions that one does not appreciate the metric system unless they have had to go through a bunch of scientific papers using really unusual units like "kilocubic feet per second" or "acre-feet".) As elevated body temperature is a symptom of COVID-19, the comic is thus also concerning the virus.
Cueball is holding what appears to be a medical thermometer, implying that he's trying to check his body temperature . He mentions that the thermometer is in Celsius, and asks how to change it.  Many thermometers sold in the United States have settings for both Fahrenheit and Celsius, with an option to change between the two. Americans are almost always more familiar with body temperatures in Fahrenheit, so Cueball presumably expects to change to that scale. However, he finds that the thermometer provides measurements in a series of scales that are increasingly unhelpful. Human body temperature in Celsius is 37 °C.
where k B is the Boltzmann constant , 1.380649×10 −23 J⋅K -1 . So if this thermometer told you a translational kinetic energy measurement in joules, you could get the measured temperature in the Kelvin scale by dividing by the Boltzmann constant and multiplying by 2/3. Somebody who actually wanted to use this measure of temperature might then find it useful to have Boltzmann's constant printed on the thermometer.
Using these last three units for home temperature gauging would be ridiculous, as Kelvin and Rankine measurements of body temperature are unfamiliar to the average user and even those familiar with them would need to do calculations to translate normal body temperature.  Kinetic energy is obscure enough that only physicists, engineers and thermodynamicists, a relative handful of the potential buyers, would likely know what it refers to. Those that do could make use of the value printed on the thermometer, but such would add a great deal of unnecessary complexity to what should be a simple and intuitive task.
In the last frame Cueball calls the thermometer the worst. It seems to lack Fahrenheit entirely, frustrating its American consumer base, including Cueball. From a nerd's perspective this would be an extraordinary device, offering even exotic temperature scales. However, a "normal person" would find this thermometer terribly difficult to use for everyday purposes when set on any of the non-Celsius scales, like checking their body temperature or the temperature of food. As an item of consumer electronics, especially one sold in the United States, it would be almost completely useless.
Deliberately lacking Fahrenheit is a jab against the Imperial system of units , and against the similar but distinct system of United States customary units . Although Imperial units and local traditional units are still used for various limited purposes (and/or by older generations) in different countries, most of the world has switched to using the metric system for most purposes going forward, with the US being relatively unusual in the extent to which it still routinely defaults to the US customary units in daily life.  Many proponents of the metric system have long pushed for the US to change over, arguing that Imperial and US customary units (and degrees Fahrenheit, specifically) are archaic and obsolete. Randall has dealt with this conflict in other strips ; as a physics major, he's partial to the metric system, and finds it frustrating to maintain multiple different scales (which is the basis of the conflict in this strip). On the other hand, he recognizes certain intuitive advantages to Imperial and US customary measurements, and recognizes that the forces of social inertia in US society make change difficult.
The title text references an archaic temperature unit, Rømer , first proposed in 1701, and is the common ancestor of both the Celsius and Fahrenheit scales. Unlike the other measurements mentioned in this strip, the Rømer scale is no longer used in any context, and only people interested in the history of temperature scales have any idea that it even exists. This is the ultimate form of obscure and outdated temperature measurements.
[Cueball stands in the center of the panel holding a thermometer.] Cueball: This thermometer is in Celsius. How do you change it? Off-panel voice: Long press the button.
[Cueball presses the button, and the thermometer beeps] Press Beep Thermometer: Units: Kelvin Cueball: No...
[Cueball presses the button, and the thermometer beeps] Press Beep Thermometer: Units: Degrees Rankine Cueball: What.
[Cueball presses the button, and the thermometer beeps] Press Beep Thermometer: Units: Average Translational Kinetic Energy Cueball: This is the worst thermometer. Off-panel voice: Boltzmann's constant is on the side if you need it.
In 1643: Degrees , Cueball struggles with which temperature unit to use, and ultimately tells his friend the temperature in radians , which is not a valid temperature scale.
In 1923: Felsius , Randall proposes a combined Fahrenheit/Celsius temperature scale called Felsius.


RIP John Conway

Explanation:
John Conway , an English mathematician, passed away of COVID-19 on April 11, 2020. Two days later, Randall created this memorial comic . It is the 6th memorial comic, but it is the first released in almost 5 years, since 1560: Bubblegum .
One of Conway's most famous creations was the cellular automaton known as Conway's Game of Life . A cellular automaton is a machine composed of cells, each of which can be in a different state. Every generation, each cell in the automaton may transition to a new state depending on a set of rules. (Conway's work in mathematics was vast and various, but he is perhaps best known in the field for discovering the surreal numbers , which inspired Donald Knuth to write a novel which may have been referenced back in 505: A Bunch of Rocks .)
Conway's Game of Life was first popularized to the general public in the form of a game, Life Genesis, bundled into some distributions of Windows 3.1, an operating system from the early-90s that Randall most likely used in his preteen years.
Conway's Game of Life is a 2-state automaton (i.e., every cell can be "alive" or "dead") that is implemented on a two-dimensional grid of cells using the Moore neighborhood - this means that each cell can only be influenced by the eight cells directly surrounding it, both orthogonally and diagonally. The transition rules that Conway used are as follows:
Despite the simplicity of these three rules, Conway showed that patterns of amazing complexity can nonetheless develop out of simple cell arrangements. Some patterns do not evolve at all ("still lifes"), some enter a cyclic, repeating state ("oscillators"), and some reproduce their own pattern displaced by an offset, resulting in patterns that can move across the grid under their own power ("gliders" and "spaceships"). This last category is of particular interest, as it allows the Game of Life to transmit information from one location to another, allowing for rich, dynamic behavior and even for the creation of computational machines within the automaton itself.
This comic begins with the shape of a stick figure as the starting cell configuration of the Game of Life. The black cells are "alive" and the white cells are "dead". This configuration then evolves via Conway's rules, disintegrating into nothingness except for a five-cell pattern known as a "glider", which ascends up, signifying that Conway went to heaven, and to the right. This visually suggests a "soul" breaking away as the corporeal body disintegrates. The glider is perhaps the most iconic pattern of the Game of Life, and is often used symbolically to represent the phenomenon of emergence.
Here the topology of the grid on which the cells evolve is not known, the cellular automaton can be run on many topologies, for example you can choose to make cells reappear from the opposite side once they reach an edge (similarly to the behaviour of the well known Pacman). Here once the glider reaches the top right, we know for sure that the actual grid is bigger (since the glider leaves the frame while continuing its pattern), and we are only seeing part of the full grid.
The initial state presented in the comic does actually evolve in that manner, as can be verified by entering the pattern into a cellular automaton simulator such as Golly or web services such as this one . It seems that no one else have created this pattern before. At least, despite discussion in the comments, no one has found anything to show that this is not Randall's own discovery of this pattern.
The title text simply states Conway's birth and death year: 1937-2020.
Conway's Game of Life was previously mentioned in 696: Strip Games . Cellular automata was also referenced in 505: A Bunch of Rocks .
This comic is the 18th comic in a row (not counting the April Fools' comic ) in a series of comics related to the COVID-19 pandemic . Although this comic is, of course, mainly a tribute to John Conway, the fact that he died of COVID-19 in the middle of this long series of coronavirus-related comics by Randall is relevant.
[A pixelated image of a stick figure using 21 pixels, could be a pixel Cueball, which waves with one hand up while holding the other hand down. The head consist of 7 pixels, the top row of three having two pixels beneath the two outer pixels, thus having two empty pixels beneath the central pixel. The neck and torso is a typical cross made from six pixels. The two legs are two pixels each shifted left and right of the cross. The arm to the left that waves is two pixels one down and the next back up to the level of the cross central beam. The arm to the right has the first pixel similarly but the second pixel continues one further step down. After less than one second it turns out that the image is animated, with the pixels changing according to the rules of Conway's Game of Life. The figure splits into three groups, two of which dissipates in a similar way at the bottom of the panel. The other becomes a 'glider' and moves off to the top-right corner of the image and out of the frame. The animation then repeats.]
Some clients of the site crashed on this xkcd, most notably the Samsung Smart TV client.


Coronavirus Charts

Explanation:
This comic is the 19th comic in a row (not counting the April Fools' comic ) in a series of comics related to the COVID-19 pandemic .
During the current outbreak of COVID-19, there have been many graphs used by health officials and others to show trends in infection and death rates. Their x-axis is usually time. The curves might represent different countries or different mitigation strategies. But
health officials and media have struggled to decide what to put on the y-axis. Because testing strategies and reporting are so variable across even small regions, their data does not reflect comparable guesses at the true number of cases. So they produce graphs of confirmed cases, confirmed plus suspected cases, deaths, hospitalizations, any of the above per capita, day-to-day changes in any of the above, and share of test results that are positive for different areas of New York .
This graph, however, while sharing similarities with actual data and graphs is completely useless. This is due to the bizarre data-points being used, as well as the unhelpful graph axes. The caption of the comic notes as much, perhaps indicating that this comic is intended to satirize the useful, but exceptionally detailed graphs that are currently in use. Some of these graphs have a semilog scale, like this graph - but generally the y-axis is the log scale and the x-axis is not. Sometimes the other graphs compare things of vastly different sizes - as demonstrated by showing both the USA and New York. Sometimes they scale the data to population, as referenced by the title text.
In addition, the selection of geographic areas used here is incomprehensible. Two of the lines represent countries (USA and Italy), and another represents part of one of those countries (New York City area). The New York City area may have been chosen because it has a very large number of cases, more than some countries. However, a fourth line combines Norway and Sweden -- two countries which are culturally, economically, and geographically similar but have imposed very different strategies regarding closing businesses and schools. Combining Norway and Sweden obscures any differences attributable to their different policies regarding the virus. A fifth line represents not a geographical area but the ratio between France and Spain, making an already meaningless graph even less comprehensible.
The title text adds a further ambiguity: Usually, there are only two items being compared in a "vice versa" (e.g. "Would you rather have live in a city with the land size of San Francisco and the population density of Tokyo, or vice versa?" when comparing two other cities with those measurements); here there are three , leading to either ambiguity ( possibly two South Korea lines, each based on one of two complementary sets of cross-demographic refactoring), or six lines being embodied in that "vice versa".
Other metrics used
X-axis:
Y-axis:
Title text: While adding data for South Korea might be helpful (as it shows an Asian country, compared to just Europe and the US), it is only logical to scale the data to the population of another country (e.g. Japan) if you're actually comparing the two countries (i.e. does Japan have more or fewer cases per capita than South Korea).  Scaling cases based on land area is much less useful; it's true that countries with lots of land area , like Australia, do have lower population densities, which affects the spread of disease, but most of the people in Australia live in higher-density cities on the coast, so the actual change is not that great.
[A graph is drawn.]
[A curve labeled "United States" starts about halfway up the vertical axis, rises almost to the top, and then levels off about a third of the way along the horizontal axis.] [4 other curves are also shown, labeled "New York City area", "Italy", "Norway + Sweden" and "Ratio between France and Spain".] Y-axis label: Coronavirus deaths today plus total cases one week ago per capita X-axis label: Negative test results per Google search for "COVID" (log scale) Caption: I'm a huge fan of weird graphs, but even I admit some of these coronavirus charts are less than helpful.


Garbage Math

Explanation:
This comic illustrates the " garbage in, garbage out " concept using mathematical expressions. It shows how, if you have garbage as inputs to your calculations, then you will likely get garbage as a result, except when you multiply by zero, which eliminates all uncertainty of the result.
The propagation of errors in arithmetic , other mathematical operations , and statistics is described in colloquial terms. Numbers with low precision are termed garbage, while numbers with high precision are called precise. The table below quantifies the change in precision from the operands to their result in terms of their variance , represented by σ, the Greek lowercase letter sigma, equal to the standard deviation , or the square root of the variance. Variance or standard deviation are common specifications of uncertainty (as an alternative to, for example, a tolerance interval .)
The accuracy and precision of mathematical operations correspond to the rules of propagation of uncertainty , where a "garbage" number would correspond to an estimate with a high degree of uncertainty, and a precise number has low uncertainty. The uncertainty of the result of such operations will usually correspond to the term with the highest uncertainty. The rule about N pieces of independent garbage used to calculate an arithmetic mean reflects how the central limit theorem predicts that the uncertainty (or standard error ) of an estimate will be reduced when independent estimates are averaged.
The title text refers to the computer science maxim of "garbage in, garbage out," which states that when it comes to computer code, supplying incorrect initial data will produce incorrect results, even if the code itself accurately does what it is supposed to do. As we can see above, however, when plugging data into mathematical formulas, this can possibly magnify the error of our input data, though there are ways to reduce this error (such as aggregating data). Therefore, the quantity of garbage is not necessarily conserved , in contrast to other scientific quantities like energy and momentum that are always conserved. Alternatively, this could be take as a pun on environmental conservation efforts, which can often involve recycling one's trash. However, the computer science maxim of "garbage in, garbage out," has nothing to do with actual garbage.
[A series of mathematical equations are written from top to bottom]
Precise number + Precise number = Slightly less precise number
Precise number × Precise number = Slightly less precise number
Precise number + Garbage = Garbage
Precise number × Garbage = Garbage
√ Garbage = Less bad garbage
Garbage² = Worse garbage
1/N Σ (N pieces of statistically independent garbage) = Better garbage
(Precise number) Garbage = Much worse garbage
Garbage – Garbage = Much worse garbage
Precise number / ( Garbage – Garbage ) = Much worse garbage, possible division by zero
Garbage × 0 = Precise number


Sourdough Starter

Explanation:
This comic is another comic in a series of comics related to the COVID-19 pandemic .
Recently, because of the coronavirus, many people are forced to stay home in quarantine or under Stay-at-home orders . These conditions often lead to spare time that needs to be filled, and many people have turned to baking, which can usually be done entirely at home, is relatively time-consuming, and has the advantage of producing finished food, lessening the need to go out to buy food. This trend is common enough that baking supplies, including yeast, have seen a spike in demand, to the point where many people have trouble finding it.
As an alternative to yeast, consumers can grow their own sourdough starter, which is a symbiotic culture of yeast and bacteria naturally found in flour. Once the starter has matured, part of it can be used to make bread or other baked good rise, while the remainder can be mixed with more water and nutrients to allow the remaining yeast and bacteria to multiply once again. Because these populations need to be maintained, it's often been a practice to trade starters from house to house, with each home using starter when they need it, then setting up the remaining starter to breed more. This has historically been a social activity, allowing people who share an interest in baking to meet, share recipes, and spend time together.
The upshot of all of this is that the coronavirus pandemic has created conditions in which yeast (and symbiotic bacteria) are being bred in larger numbers, both by companies trying to fill demand, and by individuals trying to make their own. The joke is that this outcome is, in fact, the entire purpose of the coronavirus, which is in a symbiotic relationship with yeast. The entire global pandemic, by this logic, is directed to keep humans indoors and baking so that more yeast (and bacteria) is bred. The practice of swapping sourdough starters means that they're propagated more widely, increasing and distributing the yeast population (while potentially giving the virus more opportunity to spread, as people socialize).
As Randall points out, this cycle is extremely convoluted.  However, it is not unknown for parasites to drive the responses of other creatures in order to propagate themselves. For example, Toxoplasma gondii infects mice, but can only reproduce when it infects cats.  The organism has therefore adapted to infect the nervous systems of mice, making them extremely reckless, increasing their odds of being caught and eaten by cats, allowing the the parasite to move to a new host.  Some flatworm parasites have very complex life cycles that involve four different host animals .
Randall has previously speculated about unusual parasitic organisms in 2246: Christmas Presents , in which he "concluded" that Christmas presents are parasites of Christmas trees, possibly mediated by a fungus. And in 1664: Mycology a fungus infects human brains making them wish to study (and thus grow more of) this fungus.
Viruses are not organisms (lacking some of the defining features of life), and it is debatable whether they would be considered parasites. Moreover, this theory is obviously implausible for a number of reasons.  The most obvious being that natural responses, particularly of viruses and simple organisms, evolve over a long time scale.  SARS-CoV-2, the virus responsible for the current pandemic, has very likely been infecting humans for less than one year, certainly not long enough to evolve such a complex set of behaviors. At the same time, a symbiotic relationship would require yeast to somehow contribute to the life cycle of the coronavirus in a meaningful way, which is unlikely when the yeast is being artificially bred in isolated containers.  If however, as suggested by the title text, people getting together to swap yeast starters after the lockdown ends does cause the virus to begin spreading in humans again as a result of the social contact, then the yeast would be contributing to the life cycle of the coronavirus, in an equally convoluted way.  The humor, therefore, is derived from the fact that this is a comical exaggeration, but based on cycles that actually do happen in nature.
[Cueball stands in front of a kitchen counter looking down at a glass jar he is holding in both hands. The jar's flat lid is lying on the table. There is another large jar farther back on the counter with a lid, with a small handle, on. In both jars there is a substance, which do stay in the same position in the jar even though Cueball tilts the jar he is holding.] Cueball: My sourdough starter is coming along nicely!
[Caption below the panel] Theory: The coronavirus is a yeast symbiont with an extremely convoluted parasitic life cycle.


Use or Discard By

Explanation:
Many products carry a "Use By", " Expiration date ", "Discard by" or similar date.  The date shows the latest date by which the product has been verified to provide its expected use. For example, a foodstuff will have a "consume by" date, showing the date after which the food may be unsuitable for eating.  For most products, this is a conservative estimate, especially if a product is kept sealed and stored in a cool, dark place. A few products become dangerous to use after that point, some simply become stale and less palatable (as in the case of foods) or lose potency. For most consumer items, there's no immediate imperative to discard a product as soon as it expires; you simply take the risk of a decline in quality or reliability.
One of the issues around expiration dates is that the language used tends to be arbitrary and ambiguous. Some have explicit instructions to the consumer, such as "use by:", others have instructions to the seller, such as "sell by:", still others say things such as "best by:" or "freshest before:". This can make it confusing how important it is to get rid of a given product on that date.
In this comic, two similar emergency flare guns , an item typically used to send out distress flares , have slightly different expiry instructions. One has an instruction to "use by or discard by" a specific date (in this case, three days after the date of publishing).  The other has an instruction to "use by" this date. These two phrases almost certainly have the same intent. There would be no reason to actually fire the flare.  Even the instructions to discard the flare gun really just mean that the manufacturer cannot guarantee that it will work past the printed date, and so do not advise counting on it in an emergency situation.
Despite this implication, Megan seems to take the latter instruction literally, as an order to actually fire the flare gun prior to the expiration date, whether or not it's necessary. It may be taken that she wants the experience of firing a flare, and takes that instruction as an excuse to do so. Cueball immediately objects to this line of reasoning. Firing a flare unnecessarily is generally a bad idea. It could summon emergency responders to a non-emergency situation, diverting emergency resources that may be needed elsewhere.  Even worse, if a flare is fired improperly, or in an unsafe direction, it could cause a fire and/or injuries, ironically creating an emergency situation, rather than signalling one. This was the cause of a serious fire at a Frank Zappa concert in Montreaux in December 1971, which inspired the well known song (and infamous guitar riff) " Smoke on the Water " by Deep Purple .
The title text similarly indicates that Megan intends to follow the same instructions with a can of bear spray .  Since there are no bears present, she will go camping and leave her food out to attract their attention, so that she may use the bear spray to repel bears before it "goes bad".  This would involve approaching bears (close enough to spray them) and irritating them, potentially causing them to attack if the spray is ineffective or misapplied (perhaps it only works if they smell it, but Megan might spray another part of the bear), when it would be much safer to simply discard the bear spray and not get close to bears.
Expiration dates (for food) have also been mentioned in 737: Yogurt , 1109: Refrigerator , and 2178: Expiration Date High Score .
[Megan stands in the middle of the panel, holding two flare guns, one in each hand.] Megan: These emergency flare guns are about to expire. Cueball [off-panel]: I forgot we had those.
[Cueball sitting at a desk, working on a computer.] Megan [off-panel]: This one says "Use or discard by Apr 25 2020." Cueball: Okay...
[Megan holds up one of the flare guns looking at it. She holds the other flare gun by her side.] Megan: But this one just says "Use by" ... Cueball [off-panel]: No.


Coronavirus Genome

Explanation:
This comic is another comic in a series of comics related to the COVID-19 pandemic .
It was also the first in a new series , followed in the next comic by 2299: Coronavirus Genome 2 .
Megan is a geneticist doing research on the SARS-CoV-2 virus. She is analyzing the virus's genome , its genetic material composed of RNA . The genomic sequence can be represented as a list of nucleotide bases ( guanine , adenine , cytosine , thymine and uracil - often abbreviated as G, A, C, T, and U).
The nucleotide sequence displayed is a 100% match to six SARS-CoV-2 sequences in public databases, all of them originating from the East Coast of the United States. The sequence is from nucleotides 26202-26280 of the virus genome and overlaps an unknown open reading frame/gene named ORF3a. One of the matching sequences is [1] . However, SARS-CoV-2 is an RNA virus, and so its genetic material (not containing any DNA) would not include thymine (T) but would use uracil (U) instead. The sequence uses the codes of DNA as RNA sequencing involves copying the genome into a DNA, and the DNA code is more familiar anyways.
Cueball is surprised that Megan and her colleagues actually use Microsoft Notepad , a simple text editor , to look at the genome, instead of more modern technology. She explains that better research institutions use Microsoft Word , a more advanced editor, to allow additional formatting (such as bolding and italics ), and humorously calls this " epigenetics ". In the real world, epigenetics is the study of changes that are not caused by changes in nucleotides, but by chemical modifications of DNA or chromosomes that cause changes in patterns of gene expression and activation, sometimes several generations down.  This might be considered analogous to altering the meaning of a text by changing its formatting rather than the content; for example, content can be moved into parentheses or footnotes to be de-emphasized, or rendered in boldface or enlarged to attract attention and emphasize key points. Much as text can be wrapped in HTML tags or similar markup to change its formatting, nucleotides can be methylated to prevent transcription, and the histones around which DNA is wound can also be modified to promote or repress gene expression. During DNA replication, these modifications are often also reproduced.
The real punchline comes when Megan uses spellcheck to detect mutations in the genome by adding the previous genome to spellcheck and comparing them. Overall, Megan uses ridiculously and humorously crude methods to analyze a major genetic item. The genome of SARS-CoV-2 is almost 30,000 base-pairs long, which exceeds the longest words of any natural language by two orders of magnitude (the longest words ever used in literature -- i.e. not constructed in isolation simply for the purpose of being a long word, or chemical formulas -- approach 200 letters), and may exceed the capabilities of any available spell-checking program. Furthermore, a spellcheck program underlines the whole word if a single letter is wrong and not just the letter itself. Thus, it would not be able to highlight individual mutated base pairs.  Megan might be better served by using a diff tool, but most scientists generally use commercial software that is designed to view, annotate, and edit DNA sequences (eg: Snapgene, Geneious, DNAstrider, ApE).
The title text mentions grammar checking and claims that whoever discovers how to use that to compare genomic material should be awarded a Nobel Prize . Spell-checking is analogous to comparing sequences against ones previously known, an activity that is the bread and butter of bioinformatics nowadays. Grammar checking would be analogous to having some sort of sense as to how well all the sequences generally cooperate and interact to create possibly viable functionality in an organism, something we are unable to do at the moment except in very limited ways and only in a few simple cases. It may also be a snarky commentary on the untrustworthy nature of grammar-check programs in general, which often follow grammatical rules far more strictly than is practical; it's not uncommon for an author to follow a grammar-check recommended correction only to find the corrected portion is now part of a longer portion that the checker deems "incorrect".
Amusingly, this and the title text foreshadowed the usage of an MIT language learning algorithm to predict mutations in SARS-CoV-2.
[Megan sits at a desk, working on a laptop. A genome sequence is displayed on her laptop screen, shown with a jagged line in a text bubble.] Cueball (off-screen): So that's the coronavirus genome, huh? Megan: It is! Laptop: <A long string of unintelligible letters, presumably the genome>
[Cueball walks up and stands behind Megan, still working on the laptop.] Cueball: It's weird that you can just look at it in a text editor. Megan: It's essential! Megan: We geneticists do most of our work in Notepad.
[A frameless panel, Cueball still standing behind Megan. Megan rests her arm on the chair. ] Cueball: Notepad? Megan: Yup! Nicer labs use Word, which lets you change the genome font size and make nucleotides bold or italic. Cueball: Ah, okay. Megan: That extra formatting is called "epigenetics".
[A regular panel. Cueball still stands behind Megan, this time with his hand on his chin.] Cueball: Hey, why does that one have a red underline? Megan: When we identify a virus, we add its genome to spellcheck. That's how we spot mutations. Cueball: Clever!