explain xkcd - User contributions [en]

1628: Magnus

2016-01-11T15:06:19Z

173.245.54.67: Removing Opinion, Changing Tone, Fixing small grammar issues, cutting out ellipses.

{{comic
| number = 1628
| date = January 11, 2016
| title = Magnus
| image = magnus.png
| titletext = In the latest round, 9-year-old Muhammad Ali beat 10-year-old JFK at air hockey, while Secretariat lost the hot-dog-eating crown to 12-year-old Ken Jennings. Meanwhile, in a huge upset, 11-year-old Martha Stewart knocked out the adult Ronda Rousey.
}}

==Explanation==
{{incomplete|}}

[[Cueball]] shows [[Megan]] an [https://itunes.apple.com/app/play-magnus/id808138395?mt=8 iOS app] that allows one to simulate playing {{w|chess}} against {{w|Magnus Carlsen}} at various ages. Magnus is a {{w|chess grandmaster}} who was ranked no. 1 in the world when this comic, sharing his named, was released.

The idea behind the app is that as Magnus grows up he becomes better at chess and thus it become exceedingly difficult to beat him as he gets older. Cueball could actually have beaten Magnus when he was just 8½-year-old, but already half a year later Magnus had progressed beyond Cueball's chess skills.

Megan then exclaims that she wants to have such an app for other games as well, and mentions two types of sport, {{w|tennis}} and {{w|Swimming (sport)|swimming}}, where a persons skill cannot be simulated in an app as with chess. She want's to compare herself to an 8-year-old {{W|Serena Williams}}, a professional tennis player who was ranked no. 1 on the women's singles player world ranking when this comic was released. Or to a 6-year-old {{W|Michael Phelps}} who is the {{w|List_of_multiple_Olympic_medalists#List_of_most_Olympic_medals_over_career|most decorated Olympian competitor}} of all time, with a total of 22 medals in three {{w|Olympiads}}.

Cueball is not even satisfied with just looking into sport, and wish to find out if he could cook better than for instance an 11-year-old {{W|Martha Stewart}}, who among other things, has published several cookbooks. ''Martha Stewart's Cooking School'', debuted on {{w|PBS}} in October 2012. Each episode covers cooking techniques based on her book of the same name. Megan suggest finding out if she could have won the eating contest against a 12-year old JFK. {{W|John F. Kennedy}} was the 35th President of the United States, and got assassinated in 1963.

Being the nerds that they are, Cueball and Megan continues developing their idea into a program that simulates what famous people (or animals) could do at a certain age, often not even looking at the things they are famous. They finally end up comparing 8-year-old Magnus' swimming skill against 9-year-old Martha's (he wins). But those two would both loose a {{w|hot dog}}-{{w|Competitive eating|eating contest}} against the 2-year-old horse {{W|Secretariat (horse)|Secretariat}} which won the {{w|Triple Crown of Thoroughbred Racing (United States)|Triple Crown}} in 1973 (it died in 1989). At this point even Megan realizes their project is weird.

The title text continues the theme of the last panel with more comparisons, leading to the ludicrous situation of a young Martha Stewart knocking an adult {{W|Ronda Rousey}} unconscious. This is a reference to Rousey's {{w|UFC_193#Rousey_vs._Holm_fight|fight}} against {{w|Holly Holm}}. When this comic was released, Rousey was the top ranked female {{w|bantamweight}} fighter in the world according to the {{w|Ultimate Fighting Championship}} (UFC). Rousey, who was then the female bantamweight champion for five championships straight, was largely expected to come out on top before being knocked out in less than 30 seconds.

Others famous/known people are mentioned in the title text. The first is {{W|Muhammad Ali}}, a boxer who is "among the greatest heavyweights in the history of the sport", as it says on his wiki page. The 9-year-old Ali manages to beat a 10-year-old JFK in {{w|air hockey}}. Air hockey was not invented when Ali was a kid, but it came out in the early 70s so maybe JFK actually played while he was a kid (he was from 1961).

The horse is also mentioned again in the title text, this time losing in a hot dog eating contest against 11-year-old {{W|Ken Jennings}}. Ken currently holds the record for the longest winning streak on {{W|Jeopardy!}}.

Note that there is no relationship between the age that different people are compared at.

==Transcript==
:[Cueball walks from the right towards Megan while holding up his pokédex.]
:Cueball: Magnus Carlsen has an app where you can play chess against a simulated version of him at different ages.
:Cueball: I can beat the 8½-year-old, but lose to him at 9.

:[While Megan talks to Cueball he lifts his hand to his chin, while holding the pokédex down.]
:Megan: I want that, but for other games. Can I beat 8-year-old Serena Williams at Tennis? Swim laps faster than a 6-year-olf Michael Phelps?
:Cueball: We should make a simulator.

:[Cueball walks out left and Megan follows him. He must have pocketed his phone as it is not in his hand.]
:Cueball: ...Why limit it to games? Can I cook a better chicken than 11-year-old Martha Stewart?
:Megan: Win an eating contest against 12-year-old JFK?

:[At the top frame of this panel there is a small frame with a caption. Below lies Megan on the floor to the left in front of her laptop, while Cueball sits on the floor to the right facing her in front of his own laptop. Between them are some heavy books.]
:Soon...
:[Cueball and Megan sitting at laptops in the bottom of the panel.]
:Megan: Looks like 8-year-old Magnus Carlsen can swim faster than 9-year-old Martha Stewart.
:Cueball: But they both lose a hot-dog-eating contest to 2-year-old Secretariat.
:Megan: This project has gotten weird.

==Trivia==
The app they are talking about is called [http://magnuscarlsen.com/playmagnus Play Magnus].

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring real people]]
[[Category:Comics featuring John F. Kennedy]]
[[Category:Chess]]
[[Category:Sport]]
[[Category:Animals]]

1354: Heartbleed Explanation

2014-04-11T15:48:34Z

173.245.54.67: /* Explanation */

{{comic
| number = 1354
| date = April 11, 2014
| title = Heartbleed Explanation
| image = heartbleed_explanation.png
| titletext = Are you still there, server? It's me, Margaret.
}}

==Explanation==
The {{w|Heartbleed bug}} has received a lot of news coverage recently and was also the topic of the previous comic ([[1353]]). This comic explains how the bug may have been discovered and can be exploited to reveal a server's memory contents. A hypothetical cracker (Meg) sends heartbeat requests to the server, the server responds to the heartbeat request by returning the contents of the body of the request up to the number of letters requested. The first two requests are well formed, requesting exactly the number of characters in the request body. The server is shown "thinking" about Meg's request with many other thoughts going on at the same time, analogous to the internal memory contents of a real web server. The last request sends "HAT" but requests 500 letters, the server - unaware that 500 letters is larger than the request body - returns "HAT" plus 497 letters that happened to be next to the word "HAT" in its memory. Included are many sensitive bits of information, including a master key and user passwords. One of the passwords shown is "CoHoBaSt", a reference to [[936]].

Often popular explanations of security bugs require the issue to be simplified a lot and to leave out a lot of details. But in this case the bug is actually that simple. Also, note that any client which can connect to the server can typically exploit this bug in the underlying OpenSSL software - the use of the term "User Meg" does not imply that Meg had to authenticate first.

The hover text is a reference to ''{{w|Are You There God? It's Me, Margaret.|Are you there God? It's me, Margaret.}}'' a novel by Judy Blume. The name Meg may also be intended as a variant of the conventional Mallory/Mallet "malicious attacker" from {{w|Alice_and_Bob#Cast_of_characters|cryptography's Usual Suspects}}.

==Transcript==
{{incomplete transcript}}
:'''How the Heartbleed bug works:'''
:Megan: Server, are you still there? If so, reply "POTATO" (6 letters).
:Server (amongst other thoughts): User Meg wants these 6 letters: POTATO.
:Server: POTATO
:Megan: Server, are you still there? If so, reply "BIRD" (4 letters).
:Server (amongst other thoughts): User Meg wants these 4 letters: BIRD.
:Megan: Hmm...
:Server: BIRD
:Megan: Server, are you still there? If so, reply "HAT" (500 letters).
:Server (amongst other thoughts): User Meg wants these 500 letters: HAT.
:Server: HAT. Lucas requests the "missed connections" page. Eve (administrator) wants to set server's key to "14835038534". Isabel wants pages about "snakes but not too long". User Karen wants to change account password to "CoHoBaSt". User Amber requests pages...
:[Megan is seen writing this down.]

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Computers]]

1354: Heartbleed Explanation

2014-04-11T15:36:21Z

173.245.54.67: /* Explanation */

{{comic
| number = 1354
| date = April 11, 2014
| title = Heartbleed Explanation
| image = heartbleed_explanation.png
| titletext = Are you still there, server? It's me, Margaret.
}}

==Explanation==
The {{w|Heartbleed bug}} has received a lot of news coverage recently and was also the topic of the previous comic ([[1353]]). This comic explains how the bug may have been discovered and can be exploited to reveal a server's memory contents. A hypothetical cracker (Meg) sends heartbeat requests to the server, the server responds to the heartbeat request by returning the contents of the body of the request up to the number of letters requested. The first two requests are well formed, requesting exactly the number of characters in the request body. The server is shown "thinking" about Meg's request with many other thoughts going on at the same time, analogous to the internal memory contents of a real web server. The last request sends "HAT" but requests 500 letters, the server - unaware that 500 letters is larger than the request body - returns "HAT" plus 497 letters that happened to be next to the word "HAT" in its memory. Included are many sensitive bits of information, including a master key and user passwords. One of the passwords shown is "CoHoBaSt", a reference to [[936]].

Often popular explanations of security bugs require the issue to be simplified a lot and to leave out a lot of details. But in this case the bug is actually that simple. Also, note that any client which can connect to the server can typically exploit this bug in the underlying OpenSSL software - the use of the term "User Meg" does not imply that Meg had to authenticate first. The name Meg may be intended as a variant of the conventional Mallory/Mallet "malicious attacker" from {{w|Alice_and_Bob#Cast_of_characters|cryptography's Usual Suspects}}.

The hover text is a reference to ''{{w|Are You There God? It's Me, Margaret.|Are you there God? It's me, Margaret.}}'' a novel by Judy Blume.

==Transcript==
{{incomplete transcript}}
:'''How the Heartbleed bug works:'''
:Megan: Server, are you still there? If so, reply "POTATO" (6 letters).
:Server (amongst other thoughts): User Meg wants these 6 letters: POTATO.
:Server: POTATO
:Megan: Server, are you still there? If so, reply "BIRD" (4 letters).
:Server (amongst other thoughts): User Meg wants these 4 letters: BIRD.
:Megan: Hmm...
:Server: BIRD
:Megan: Server, are you still there? If so, reply "HAT" (500 letters).
:Server (amongst other thoughts): User Meg wants these 500 letters: HAT.
:Server: HAT. Lucas requests the "missed connections" page. Eve (administrator) wants to set server's key to "14835038534". Isabel wants pages about "snakes but not too long". User Karen wants to change account password to "CoHoBaSt". User Amber requests pages...
:[Megan is seen writing this down.]

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Computers]]

690: Semicontrolled Demolition

2014-01-29T13:34:09Z

173.245.54.67: The explanation seems complete

{{comic
| number = 690
| date = January 18, 2010
| title = Semicontrolled Demolition
| image = semicontrolled demolition.png
| titletext = I believe the truth always lies halfway between the most extreme claims.
}}

==Explanation==
The {{w|World Trade Center}} towers were destroyed on September 11, 2001 (9/11 in American date notation). The planned attack was for two planes to collide with the north and south towers simultaneously, but what ended up happening was that [http://www.youtube.com/watch?v=7g6V8KZE3GA&t=35s plane 1 hit the north tower at 8:46 am], and [http://www.youtube.com/watch?v=7KYE4zViAAg&t=11m44s the second plane hit the south tower a little less than 20 minutes later]. In the ensuing investigation many people raised questions that didn't seem to get a satisfactory answer for several months, if not years. Many people, who called themselves {{w|9/11 Truthers}}, began to claim that the whole thing was a government conspiracy, in what has come to be known as the "controlled demolition plot" (referenced by the title of this comic), which alleges that the towers were brought down not by the fires caused by the planes but by demolition charges intentionally placed there by the government.

[[Randall]] proposes a compromise to make both those who believe in the conspiracy and those who don't happy. Since there is no video of a plane flying into the north tower (as no one expected the crash), that was a government conspiracy. But it just so happened that the government decided to demolish the north tower on the same day that terrorists decided to demolish the south tower.

The title text is a restatement of the {{w|Argument_to_moderation|Golden Mean fallacy}}: that the truth can be found in a compromise between two opposite positions. In this comic, one of the positions is a fanciful conspiracy theory and the other is a sober fact-based conclusion. The error of this fallacy is apparent here, as it can lead to even more ridiculous conclusions.

==Transcript==
:[Cueball is holding up a pointer to a screen with an image of the World Trade Center towers mid-disaster.]
:Cueball: Based on my analysis, I believe the government faked the plane crash and demolished the WTC north tower with explosives.
:Cueball: The south tower, in a simultaneous but unrelated plot, was brought down by actual terrorists.

:The 9/11 truthers responded poorly to my compromise theory.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Public speaking]]
[[Category:Comics presenting a compromise]]
[[Category:Conspiracy theory]]

Talk:1300: Galilean Moons

2013-12-06T20:34:40Z

173.245.54.67: /* Animation is incorrect */

"most likely Callisto, the outermost of the four" - seems that it's definitely Callisto, since its drawn with little craters - no?

Hmmm. The animation just added agrees with another animation I've seen, in that the three innermost moons never line up all on one side of Jupiter at the same time. So if "Hi" (Io) and "What's your name" (Europa) conjoin on the right side as we're looking, then "What's your name" and "MOOOON!" (Ganymede) should conjoin on the left side. Not that I'm being critical of course...

[[User:Just some guy|Just some guy]] ([[User talk:Just some guy|talk]]) 05:39, 6 December 2013 (UTC)

Some javascript application available on the net to see the 4 moons orbits around [http://www.skyandtelescope.com/observing/objects/javascript/jupiter jupiter]

[[User:HmmmHmmm|HmmmHmmm]] ([[User talk:HmmmHmmm|talk]]) 06:48, 6 December 2013 (UTC)

If the inner moons are tidally locked with Jupiter, can you ostensibly state that they're mooning the outer moons, whenever two such moons line up? lol [[Special:Contributions/108.162.222.209|108.162.222.209]] 08:57, 6 December 2013 (UTC)

Even with the resonance, "MOOOOOON!" appears still not to have been able to escape with that effect alone until Cueball's own close approach to Megan brought his own gravity well close enough to hers to give rise to a viable transfer orbit. And appears to be now retrograde, relative to its last orbit. Or possibly on a free-return path, unless Cueball steps back before the return transfer happens or makes an appropriate sideways move to quash the orbital potential. [[Special:Contributions/141.101.99.229|141.101.99.229]] 09:34, 6 December 2013 (UTC)
:Hang on... "MOOOOOON!" isn't the "Ugh/So annoying/Almost/Yes!" one. Forgot to note the hint of shading. Still, the above applies to the disgusted/elated moon, clearly not liking either of the Valley Girls ''or'' the loudmouth Jock. [[Special:Contributions/141.101.99.229|141.101.99.229]] 09:38, 6 December 2013 (UTC)

Is it just me or does "MOOOOOON!" have a subtle [http://knowyourmeme.com/memes/moon-moon "MOON MOON"] undertone? [[Special:Contributions/141.101.96.4|141.101.96.4]] 12:26, 6 December 2013 (UTC)

Am I the only one thinking that the "MOOOOOON!" is a reference to the "SPAAAAACE!" module from portal 2?
No
*I saw a possible reference to [http://www.wondermark.com/302 "Wondermark"]. [[Special:Contributions/173.245.54.5|173.245.54.5]] 15:14, 6 December 2013 (UTC)

Maybe moons converse with Cueball, not between them itself?
[[Special:Contributions/173.245.53.180|173.245.53.180]] 13:14, 6 December 2013 (UTC)

Or with Megan, when opposite to her face?
[[Special:Contributions/173.245.53.180|173.245.53.180]] 13:39, 6 December 2013 (UTC)

:I think the moons are clearly conversing with Cueball. Remember that Io executes a full orbit between every panel. --[[User:BlueMoonlet|BlueMoonlet]] ([[User talk:BlueMoonlet|talk]]) 17:27, 6 December 2013 (UTC)

== Animation is incorrect ==

The current animation has the wrong speed of the outermost moon, which is currently orbiting at a 5:1 ratio to the innermost. They should all line up along a vertical line once every four rotations. In fact the current animation never lines up all three moons at the same time (at least, not on the same side of the planet). -Greg
[[Special:Contributions/108.162.215.10|108.162.215.10]] 16:06, 6 December 2013 (UTC)
:The animation is correct. If you look closely at only Europa and Ganymede, you'll see that they are also in a 2:1 resonance, with conjunctions always taking place at the "6 o'clock" position. Io and Ganymede are in a 4:1 resonance, with conjunctions taking place at 12 o'clock, 4 o'clock, and 8 o'clock. The comic is incorrect in having all three moons on the same side of Jupiter at the same time. That never happens in the actual system, though I don't mind it in the name of artistic license. --[[User:BlueMoonlet|BlueMoonlet]] ([[User talk:BlueMoonlet|talk]]) 17:27, 6 December 2013 (UTC)
::The innermost orbit completes 5 rotations for each 1 of the outermost. How is that a 4:1?
::[[Special:Contributions/108.162.215.10|108.162.215.10]] 18:16, 6 December 2013 (UTC)
:::I think you need to count more carefully. Start when both moons are at "12 o'clock". In the time it takes for Ganymede to get back to that position, I see Io go around 4 times. --[[User:BlueMoonlet|BlueMoonlet]] ([[User talk:BlueMoonlet|talk]]) 18:19, 6 December 2013 (UTC)
::: You're probably counting from 1 to 5, instead of from 0 to 4. I.e. When they're lined up to start, you could call that conjunction #1, but they've done 0 orbits. [[User:Wwoods|Wwoods]] ([[User talk:Wwoods|talk]]) 19:42, 6 December 2013 (UTC)
::If it was five to one the planets would line up every other orbit of Ganymede [[Special:Contributions/173.245.54.67|173.245.54.67]]