Explain xkcd: It's 'cause you're dumb.
This strip uses a play on the homophonic relationship between "canon", the literary term, and "cannon", a projectile weapon.
In terms of a given literary series, canon describes a set of works that are collectively recognized by the community as having authenticity. Generally, works created or endorsed by the original author(s) are considered canonical. Not all original content is considered canon and not all canon is original content. Sometimes creators will rewrite the canon (called a retcon) and make things that were previously canonical non-canonical. For example, the origins of a character may be rewritten, thus invalidating the portions of the works that speak to the old origins. Other times creators will incorporate non-original content and therefore incorporate the canon of these borrowed works.
A headcanon as the name implies is a form of canon that only exists in one's mind. More specifically, a headcanon is created when a consumer watching or reading the material develops their own ideas about a fictional universe that are not actually part of the canon, perhaps developing their own backstories or experiences for characters. Some frequent examples of headcanon include relationships between characters, abilities, events following the conclusion of the work, etc. which the author or creator has not explained or included. For example, a consumer may "read between the lines" and assume that there was a previous romantic relationship between two characters where no conclusive evidence actually exists of one. Some fans who come up with particularly interesting or convincing headcanons may decide to share them with others in hopes that their idea spreads.
In this strip, Black Hat tells Cueball that he has a "new headcannon". Cueball, thinking Black Hat means "headcanon", thus inquires what Black Hat's new idea is. Instead of the expected idea or theory about a fictional universe, Black Hat removes his hat to reveal a tiny literal cannon on his head, which proceeds to blow away Cueball and his computer desk.
In the title text Randall deliberately emphasizes the comic's punch line by using three consecutive "n"s to spell "headcannnon". He also introduces the fact that a fan who introduces a headcanon may be ignored or dismissed by the rest of the community for various reasons, such as the idea being too unconvincing or implausible to be true. This may be discouraging to the fan in question. On the other hand, a fan who introduces a headcannon would be far harder to ignore and it would be far easier to convince others of the headcannon's existence, as it is a physical object which has a notable (and in this case violent) impact on the real world.
This comic also shows Cueball being once again distracted from his work in a manner similar to 1388: Subduction License.
- [Black Hat walks in.]
- Black Hat: New headcannon:
- [Cueball is sitting at his desk, using his computer.]
- Cueball: Yeah?
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- [Black Hat lifts his hat, revealing a tiny cannon on top of his head. The headcannon fires and blows up Cueball's desk, the explosion throwing Cueball backwards.]
- Headcannon: BOOM
- Cueball: AUGH!
Why are there three n's in headcannnon in the title text?
- Or as n increases the effort to convince others that the existence/correctness of headca(n)+on decreases? 22.214.171.124 20:31, 30 July 2014 (UTC)arcturius
- I think it's as simple as 1 n in canon (what the pun is based on), 2 n's in cannon (in the comic), and just to keep the pattern going, 3 n's in cannnon (in the title text).--126.96.36.199 05:35, 30 July 2014 (UTC)
That reminds me on Neil Stephensons - The Diamond Age: or A Young Lady's Illustrated Primer... Very nerdy! 188.8.131.52 (talk) (please sign your comments with ~~~~)
Another very common usage of headcanon is when you REMOVE something from your headcanon - that is, pretend that it never happened, despite it being canon. Often it's case of not-really-good sequels. Or later edits: see Han shot first. -- Hkmaly (talk) 10:35, 30 July 2014 (UTC)
- I thought that headcanon was everything fans imagined, not just what contradicts canon. --184.108.40.206 16:32, 30 July 2014 (UTC)
Anyone note that the computer is completely undamaged (from the cannonfire at least, no telling about when it strikes the floor), despite the desk being demolished? Zowayix (talk) 13:14, 30 July 2014 (UTC)
Worth mentioning the alternate term "fanon", at all? (Currently third but unlinking item Wikipedia link, or the more dangerous (in the Comic 214 sense) TVTropes link... ) 220.127.116.11 13:22, 30 July 2014 (UTC)
- I'd say no, fanon is headcanon that is accepted in huge parts of the fandom. --18.104.22.168 16:32, 30 July 2014 (UTC)
New headcanon: Black Hat Guy always has a headcannon under his hat, and in this comic he is simply showing Cueball that he got a new one. 22.214.171.124 14:12, 30 July 2014 (UTC)Matthew
- Not true. In other comics where he hasn't had his hat, he did not have a cannon on his head. 126.96.36.199 15:40, 30 July 2014 (UTC)
Canon (in Greek: Kanon, Arabic: Qanon, Hebrew: Kaneh) means reed, or straight. Thus trustworthy.  Seebert (talk) 14:38, 30 July 2014 (UTC)
Black Hat is shown to have short dark hair. That's new xkcd canon. As far as I know, he'd always been shown wearing a hat completely covering his hair until now. --Dangerkeith3000 (talk) 15:33, 30 July 2014 (UTC)
- Not new. http://xkcd.com/377/ 188.8.131.52 15:40, 30 July 2014 (UTC)
- I always assumed black hat and white hat(perhaps all the cast) were aspects of Cueball,s psyc, a jungian zoo. 184.108.40.206 (talk) (please sign your comments with ~~~~)
Ra-Ra-Rasputin 220.127.116.11 (talk) (please sign your comments with ~~~~)
"The title text is a pun on the homophones *canon* and *cannon*" ... uh, the whole entire COMIC is a pun on the homophones *canon* and *cannon*. 18.104.22.168 18:16, 30 July 2014 (UTC)
Kudos to the author(s) of the example using Quark. One of the best-written explanations on this wiki. jameslucas (" " / +) 22:42, 30 July 2014 (UTC)
"Fans might wonder why, on a station that has "replicators" (devices that can create any food or drink out of energy on demand), anyone would patronize a bar" - perhaps because they might want to, you know, socialise with other people? Call me old-fashioned... --22.214.171.124 14:23, 31 July 2014 (UTC)
Anyone know if this weeks what if is different depending on region? I only ask because it mentions my small town and I am skeptical based on past comics. 1037: Umwelt126.96.36.199 06:25, 1 August 2014 (UTC)
Well, it doesn't mention anyplace close to me :-)
188.8.131.52 09:04, 4 August 2014 (UTC)
No one has explained why the comic is titled "New". Because Black hat says "NEW HEADCANNON:" rather than "I HAVE A NEW HEADCANNON:", I think he is speaking not English, but some programming language. Black Hat created the headcannon by saying "new Headcannon:", which is a command to instantiate an object of type Headcannon. This is similar to previous strips http://xkcd.com/353/ and http://xkcd.com/413/, which attributed supernatural creative powers to Python's "import" statement. But "new Headcannon:" isn't Python. I don't know language it is. 184.108.40.206 (talk) (please sign your comments with ~~~~)
Could the "headcannnon" refer to an idea that "blows your mind"? The trajectory of the "literal" cannon ball ends where Cueball's head was, so it went from head to head, not head to desk... --B. P. (talk) 22:34, 28 October 2014 (UTC)
- It seems more likely Black Hat is just being an asshole and shooting him in the face. -Pennpenn 220.127.116.11 02:51, 23 January 2015 (UTC)