explain xkcd - User contributions [en]

1519: Venus

2016-03-25T10:27:11Z

162.158.153.113: /* Explanation */

{{comic
| number = 1519
| date = May 1, 2015
| title = Venus
| image = venus.png
| titletext = The sudden introduction of Venusian flowers led to an explosive growth of unusual Earth pollinators, which became known as the "butterfly effect."
}}

==Explanation==
[[Miss Lenhart]] is teaching a class on science about the planet {{w|Venus}}.

In the first panel we see her teaching the history of Venus. Venus may have had water on its surface billions years ago, but if that's true all hydrogen since then was eventually lost due to dissociation. However, there is no evidence that Venus ever had fields of flowers, or Venusians, or any other form of life.

The {{w|runaway greenhouse effect}} on the second panel is a play on words. Miss Lenhart uses the term literally and claims the existence of sentient greenhouses that actually ran away. In reality, the effect caused Venus to develop a thick atmosphere of carbon dioxide, which raised its temperature above to approx. 460 °C (860 °F), hotter than daytime on Mercury. This eventually destroyed all evidence of anything that had been on the surface of Venus billions of years ago.

The third panel ties the previous distortion of Miss Lenhart into the very real {{w|Tulip mania|historic reputation}} of the Netherlands as {{w|Netherlands#Agriculture|flower growers}} and as a further fabrication by Miss Lenhart the Dutch flower industry was in fact started by the Venusians.

In the final panel we see that she is a month away from retirement and doesn't care about relaying accurate information anymore. She just wants to have a laugh at the expense of the naive school children.

The title text jokes about the {{w|butterfly effect}}, the idea that a butterfly flapping its wings in Japan can cause a Tornado in the U.S.. In this case the {{w|Butterfly|butterflies}} would just help pollinate the flowers.

==Transcript==
:[Miss Lenhart is standing in front of an image, presumably a temperate Venus, with greenhouses, grass, flowers and a river flowing into a sea.]
:Miss Lenhart: Venus once was temperate. It had seas and rivers, and Venusians cultivated vast fields of beautiful flowers.

:[The image is now zoomed out to see the entirety of Venus, with continents and oceans. The greenhouses are shown fleeing ("running") away from Venus.]
:Miss Lenhart: Until their greenhouses fled the planet due to the runaway greenhouse effect.

:[Miss Lenhart is now standing in front of a classroom and addressing the students, we see one of these a girl with her hair in a bun, sitting at a desk.]
:Miss Lenhart: The Venusians pursued their greenhouses to Earth, settling in the Netherlands and kickstarting the Dutch floral industry. Any questions?

:Offscreen (Presumably Hairbun): Because you're retiring in a month, do you just not care what you say anymore?
:Miss Lenhart: ''What?!'' I '''''ride the skies''''' atop a screaming bird of truth! Also, yes, I do not.

==Trivia==
*It is not directly mentioned that it is Miss Lenhart teaching, but her looks and profession fits this character well enough to make this deduction.

{{comic discussion}}
[[Category:Comics featuring Miss Lenhart]]
[[Category:Space]]

35: Sheep

2016-03-25T10:22:28Z

162.158.153.113: Maractus did not yet exist when this comic was published

{{comic
| number = 35
| date = November 26, 2005
| title = Sheep
| image = sheep.jpg
| titletext = I think it's the sheep zapping the cactus and not vice-versa
}}

==Explanation==
Due to Randall's vacation he picked out comics from his old high-school notebooks. This is the second in a row. It was also released a day too late.

It is a very weird drawing, especially with the title text proclaiming that it may be the sheep that is zapping the cactus.

It may be a Pokémon reference, with the sheep being Mareep, and the cactus being Cacnea or Cacturne.

Also see this [[#Poem by Scott|poem by Scott]].

==Transcript==
:Another from my high-school notebooks.
:[A sheep and a potted saguaro cactus linked by an arcing yellow electricity bolt, drawn on graph paper.]

==Trivia==
*This was the 37th comic originally posted to [[LiveJournal]].
**The previous was [[41: Old Drawing]].
**The next was [[42: Geico]].
*Original title: "Friday's Drawing - Sheep"
*Original [[Randall]] quote: "I'm still on vacation, sorry this is a bit late. I forgot what day it was. Anyway, I'll be back Monday, possibly with new drawings about cereal!"
**This was the reason the Friday comic came out on a Saturday for the second week running.
**The one about cereal came out on Wednesday: [[38: Apple Jacks]]
*This comic was posted on [[xkcd]] when the web site opened on Sunday the 1st of January 2006.
**It was posted along [[:Category:First day on xkcd|with all 41 comics]] posted before that on LiveJournal as well as a few others.
**The latter explaining why the numbers of these 41 LiveJournal comics ranges from 1-44.
*One of the original drawings drawn on [[:Category:Checkered paper|checkered paper]].

===Poem by Scott===
In the comment to the original [[LiveJournal]] post there was a user called Scott who posted this original poem:
:I had a little cactus and I treasured it with pride,
:admiring its spines and dainty flowers.
:Until the day - oh tragic day! - when it was RAMIFIED,
:by a ram with strange psychokinetic powers.

:Baaing deep, this shaman sheep came whiffling through the brambles.
:It gazed upon my cactus and, with yellow flash and thudrous crash,
:with dashing, brash, and rash panache,
:it blew the plant to shambles.

:I was, I confess, horrified - I sat and cried my eyes out!
:Oh stupid sheep, satanic sheep, so wrong and rash and willful!
:I nursed the cactus best I could, till finally it came about.
:It grows apace now, once again, but all it blooms is steel wool!

[And then in another post beneath this posted four minutes after the poem at 4:57 UTC (AM?) he finished with:]
:Oh God I need sleep!

If this is the [[Scott]] that is a friend of Randall is not entirely clear...

===Other poems===
:Mary had a little lamp
:She tied it to a pylon
:Ten thousand volt went up its a**
:And turned its wool to nylon.

{{Comic discussion}}

[[Category:Comics posted on livejournal| 37]]
[[Category:First day on xkcd]]
[[Category:Checkered paper]]
[[Category:Comics with color]]
[[Category:Scott]]

Talk:454: Rewiring

2016-03-23T21:40:36Z

162.158.153.113:

As well as physically 'threading' the mail system, an email (or other messaging) client that keeps track of what messages reply to which others (often as a linear progression or cascade, or a tree-view where multiplie participants can be expected to branch the conversation) is said to show 'threaded' messages. Or was. (These days it's probably got some other name, and everyone seems to just want to top-post anyway. Thank you, Eternal September!!!) [[Special:Contributions/178.107.249.215|178.107.249.215]] 13:12, 14 June 2013 (UTC)

:If there were so many homes with phone wiring and no ethernet wiring and they were complaining, why didn't they just use the phone wiring for ethernet. It is a little less stable because of lack of addditional grounding/isolation wiring, but ethernet does only actually use 4 wires. [[User:Tharkon|Tharkon]] ([[User talk:Tharkon|talk]]) 19:35, 1 December 2013 (UTC)

:: The RJ11 jacks in more than half the houses I've lived in only had 2 wires connected. The most common reason to have 4 wires is that someone ordered two handsets in the 70s--sometimes dialing on one handset would cause the other one to ring, in which case AT&T would install an "anti-tinkle system", which required another wire pair. I also lived in one house whose owner had ordered a business phone when he lived there, and the lights on the business phone were powered by a second pair. [[Special:Contributions/162.158.255.69|162.158.255.69]] 18:44, 14 September 2015 (UTC)

I believe that there needs to be more explanation about the title text, particularly about what "threading" and a mail system are. [[User:Codefreak5|Codefreak5]] ([[User talk:Codefreak5|talk]]) 05:20, 16 July 2014 (UTC)

Hey folks, when I check the comic on my computer the title text reads "Finn", not "Elizabeth". Is this an error on this site, or is it one of Randall's meta-jokes? [[Special:Contributions/198.41.235.185|198.41.235.185]] 13:41, 4 January 2016 (UTC)
:Added an explanation. It contains all the facts of the situation that I'm aware of, but someone who frequents the chat more than I do may be able to correct me. --[[Special:Contributions/162.158.153.113|162.158.153.113]] 21:40, 23 March 2016 (UTC)

454: Rewiring

2016-03-23T21:39:52Z

162.158.153.113:

{{comic
| number = 454
| date = July 25, 2008
| title = Rewiring
| image = rewiring.png
| titletext = My friend Finn tried to mail one end of the cable to me and thread the mail system.
}}

==Explanation==
At the time this comic was written, most residential buildings in North America were wired for {{w|Analog device|analog devices}} using the old {{w|plain old telephone service|landline telephone service}}s, although thanks to the growth of {{w|internet telephone}} and wireless telephone technologies, including {{w|cordless telephone|cordless}} and {{w|mobile phone|mobile}} phones, this in-house wiring was increasingly redundant. See also {{w|Wireless telephone#Use of mobile phones|Use of mobile phones}}.

At the time, people who took their internet access seriously would have preferred that at least some of the phone wiring and phone jacks in their residences were {{w|Ethernet}} ({{w|Cat-5}} or {{w|Cat-6}}) wiring and ({{w|Modular_connector#8P8C|RJ45}}) jacks for providing wired internet access throughout their home, or in this case, to their neighbour's home, so that they wouldn't have to resort to {{w|Wi-Fi}}, which was then slower and less reliable than a wired connection ([http://www.google.ca/trends/explore?q=wireless+g%2C+wireless+n#q=wireless%20g%2C%20wireless%20n&cmpt=q Google Trends]).

The title text suggests it shows a fanciful way of converting analog phone lines to {{w|digital}} ethernet lines by simply faxing an ethernet cable, since a fax machine is a tool for {{w|digitizing|converting}} analog content into digital.

Since the faxing of the ethernet cable is apparently successful, the comic is not really about the conversion, but is instead a subtle {{w|computer network}} joke about {{w|Tunneling protocol|tunneling}}, whereby you can embed one kind of network access protocol within a very different protocol. Herein lies the humour: [[Cueball]] and [[Megan]] are apparently under the impression that they can achieve a faster connection by tunnelling a high-speed protocol (ethernet) through a slower (landline telephone service) one. Generally speaking, this is not true. The only exception is when embedding a compressed data stream within a non-compressed standard. The performance boosts, however, are typically modest for {{w|lossless compression}}, and not the orders of magnitude difference our novices apparently hope for.

The title text, which is a reference to foonetic user relsqui, was changed to correct "Elizabeth" to "Finn" after they came out as agender.

==Transcript==
:[Cueball is feeding cable into a device on a desk labeled "fax".]
:Fax: ''zzzzzz''
:[Outdoors, showing a plant and a lamp (indicates panels 1 and 3 are separate locations).]
:[Megan, laptop behind her, is pulling a cable out of a fax machine.]
:Fax: ''zzzzz''

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

1659: Tire Swing

2016-03-23T13:46:28Z

162.158.153.113:

{{comic
| number = 1659
| date = March 23, 2016
| title = Tire Swing
| image = tire_swing.png
| titletext = If we find one of those tire dumps, the next time he tries to get his truck back we can just retreat and let him have it.
}}

==Explanation==
In this comic, two characters (possibly [[Hair Bun Girl]] and [[Megan]]) have just completed a tire {{w|swing (seat)|swing}}: A common (or at least stereotypical) makeshift swing created by hanging a car (or larger) tire from a length of rope, typically tied to the branch of a tree.

Vehicle tires have a limited lifespan. The natural end of their life is when the pattern of raised treads on the circumference of the tire, which promote traction on the road, are worn down to a point where they are no longer effective enough. Tires can also become damaged in other ways, such as puncture.

Used tires are a {{w|Tire recycling}} notable ecological problem for a number of reasons (e.g. their size, the quantity produced, their relatively short lifespan, and the fact that they are difficult and slow to break down). A tire swing represents a functional use for otherwise useless old tires.

In the second panel of this comic, Hair Bun Girl muses that there are huge dumps filled with old tires that have no use. In the third panel, she continues that maybe they should use a tire from such a dump next time they make a tire swing. The presumption is that perhaps they used a brand new tire, or a tire from some other source. However, Megan's response (coupled with the title text) suggests that, in fact, the tire they used was stolen. Hair Bun's reply suggests the victim put up a fight and they had to take the tire by force.

The title text goes further, suggesting that they stole the victim's entire truck - possibly just to harvest the tire needed for the swing - and that he may have attempted unsuccessfully to recover the truck.

==Transcript==
:[Hair Bun Girl and Meagan are standing under a tree as Hair Bun Girl adjusts a tire swing hanging from one of the branches.]
:Hair Bun Girl: Ok, looks good.

:Hair Bun Girl: I read that there are these huge dumps everywhere full of millions of old tires that no one knows what to do with.

:Hair Bun Girl: We should use one of those next time.
:Meagan: Yeah. That guy was real mad.
:Hair Bun Girl: I would ''not'' want to fight him again.

{{comic discussion}}

[[Category:Comics featuring Megan]]
[[Category:Comics featuring Hair Bun Girl]]