explain xkcd - User contributions [en]

1175: Moving Sidewalks

2025-02-04T20:27:58Z

172.71.147.141: Links to OK Go Video

{{comic
| number = 1175
| date = February 18, 2013
| title = Moving Sidewalks
| image = moving sidewalks.png
| titletext = I think I could spend hours just stepping on and off of conveyor belts moving at various speeds.
}}

==Explanation==
[[Cueball]] and [[Megan]] are getting ready to ride an array of mini-conveyor belts, each going at a speed multiple of the first ones. Assuming they both take the one in front of them, each conveyor belt will speed them up a little bit more with little effort on their part, ultimately reaching a point where they are going very fast and are close enough to be able to high-five each other.

For the most central conveyor belts, there is no speed indicated: it could still be 5x, or a further increase to 6x. No number could also indicate a mere 1x or even a non-moving belt, which would make the whole setup tricky for a much different reason.

The average moving walkway speed globally is 3 feet/second (~1m/sec), so Cueball and Megan would only be travelling about 2/3 average human running speed by the time they meet. Even with the opposing forces added to their high five, it would be very unlikely for them to injure each other (though the slap would more than likely be painful). If they are additionally running along their belt setups, it might hurt some more.

The title text may be a reference to a [https://www.youtube.com/watch?v=dTAAsCNK7RA music video] made by [https://en.wikipedia.org/wiki/Here_It_Goes_Again OK Go, "Here It Goes Again"], in which the band jumps on and off of various treadmills in a similar fashion.

A series of parallel accelerating conveyor belts is also a long distance travel mechanism used in Robert A. Heinlein's {{w|The Roads Must Roll}} and in Isaac Asimov's Robot Detective novels.

==Transcript==
:[Cueball and Megan on the opposite far ends of a bidirectional moving sidewalk. Arrows indicate that one half will carry Cueball from left to right, while the other half will carry Megan from right to left. In each direction, the sidewalk is made up of a series of individual conveyors.]
:Cueball: Ready?
:
:[A diagram labels various individual conveyors as follows.]
:[Outermost conveyors:] Moving Sidewalk
:[Second and second-last conveyors:] Moving Sidewalk (2x Speed)
:[Next conveyors:] 3x Speed
:[Next conveyors:] 4x Speed
:[Innermost conveyors:] 5x Speed
:[Spot between the two sidewalks, directly in the center:] High-Five Location
:
:Megan: Ready.

==Trivia==
This comic was originally uploaded with all the arrows facing in the opposite direction, before Randall updated it with the current image.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics edited after their publication]]

Talk:3007: Probabilistic Uncertainty

2024-11-04T20:30:30Z

172.71.147.141:

Emotional spirals are useless. I've been coping by pretending we're in scenario 1, it keeps me sane. If I'm wrong, I'll jump off that bridge when we come to it. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 20:23, 4 November 2024 (UTC)

I can't help but think that at preparing for the negative outcome regardless of which outcome is more likely (unless that outcome is *very* unlikely) is a healthy thing to do. [[Special:Contributions/172.71.147.141|172.71.147.141]] 20:30, 4 November 2024 (UTC)

3001: Temperature Scales

2024-10-26T14:54:38Z

172.71.147.141: /* Examples */ Felsius

{{comic
| number = 3001
| date = October 21, 2024
| title = Temperature Scales
| image = temperature_scales_2x.png
| imagesize = 740x535px
| noexpand = true
| titletext = In my new scale, °X, 0 is Earths' record lowest surface temperature, 50 is the global average, and 100 is the record highest, with a linear scale between each point and adjustment every year as needed.
}}

==Explanation==
{{incomplete|Created by an TOTALLY CONFORMING TEMPERATURE SYSTEM. Do NOT delete this tag too soon.}}

Since the invention of the {{w|thermometer}}, a number of different {{w|temperature}} scales have been proposed. In modern times, most of the world uses the 1742 {{w|Celsius}} scale for everyday temperature measurements. A small number of countries (the USA and {{w|Territories of the United States|its territories}}, the Bahamas, Belize, the Cayman Islands, Liberia, and Palau) retain the {{w|Imperial units|imperial system}} (or the related {{w|United States customary units|US customary system}}), which uses the 1724 {{w|Fahrenheit}} scale. The other widely used temperature scale is the 1848 {{w|Kelvin}} scale, which uses the same degrees as Celsius, but is rooted at {{w|absolute zero}}, making it both useful in scientific calculations and easy to convert to and from Celsius (which, along with degrees Fahrenheit, is now defined relative to kelvins.) The Kelvin scale has been part of the widely adopted official {{w|metric system}} since 1954. Even in countries that use Fahrenheit, scientific measurements are usually made in degrees Celsius or kelvins.

The comic compares these scales, and a number of others, on [[Randall]]'s scale of "cursedness." The joke is highlighting how different the temperature scales are, and how impractical most of them are. All of the listed scales (except Randall's new °X scale defined in the title text) are real, but most are obsolete. Please see also [[1923: Felsius]], a combination of degrees Fahrenheit and Celsius.

{| class=wikitable
! scope="col" | Unit
! scope="col" | Water freezes
! scope="col" | Water boils
! scope="col" | Notes
! scope="col" | Cursedness
! scope="col" | Explanation
|-
| {{w|Celsius}} || 0 || 100 || Used in most of the world || 2/10 || The Celsius (°C) scale, also known as "centigrade", was devised by Swedish astronomer {{w|Anders Celsius}} in 1742 and revised in 1745, a year after his death. 0°C represents the freezing point of water and 100°C represents the boiling point, both under {{w|standard atmospheric pressure}}. The Celsius scale is now defined in terms of kelvin. By the given "cursedness," it is regarded as one of the least problematic temperature scales.
|-
| {{w|Kelvin}} || 273.15 || 373.15 || 0K is absolute zero || 2/10 || Kelvins (plural with a lowercase 'k' as a temperature unit, like meters, ohms, watts, and amps; or as the symbol 'K', without the degrees symbol '°', unlike most other such units) are a unit of temperature devised by {{w|Lord Kelvin}} in 1848. It uses the same degrees as Celsius but is shifted by 273.15 to set absolute zero at 0K (based on the {{w|Boltzmann constant}}.)
<center>Celsius = kelvin - 273.15</center>
<center>kelvin = Celsius + 273.15</center>
While kelvins are very useful for calculations in {{w|thermodynamics}} and material physics, it can be unintuitive to laypersons.
|-
| {{w|Fahrenheit}} || 32 || 212 || Outdoors in most places is between 0–100 || 3/10 || Fahrenheit (°F) is officially used in a few countries and informally in several others. It originated in a time when factors of 360 were favored in science over powers of ten, which is why the freezing and boiling points of water are set 180° apart. Devised around 1724, {{w|Daniel Fahrenheit}} chose not to base 0° on the freezing point of water, instead originally setting it at the coldest temperature he could achieve: the freezing point of an {{w|ammonium chloride}} {{w|brine}} solution.
<center>Celsius = (Fahrenheit - 32) × 5/9</center>
<center>Fahrenheit = Celsius × 9/5 + 32</center>
Although those reference points are now considered arbitrary and outdated by modern scholars, the scale gained popularity in Anglophone countries, possibly because everyday weather conditions usually fall handily all across the range 0–100°F, and 100°F is {{w|Human body temperature#Historical understanding|coincidentally close to normal human body temperature}}. The Fahrenheit scale remains officially used only in Randall's home country (the U.S., and its territories), the Bahamas, Belize, the Cayman Islands, Liberia and Palau.
|-
| {{w|Réaumur scale|Réaumur}} || 0 || 80 || Like Celsius, but with 80 instead of 100 || 3/8 || Abbreviated as °Ré, this system devised by {{w|René Antoine Ferchault de Réaumur}} in 1730 was used in some places until the early 20th century, mostly for cheese-making.
<center>Celsius = Réaumur / 0.8</center>
<center>Réaumur = Celsius × 0.8</center>
The rating (3/8) is a joke on the boiling point of water in this system being 80 instead of 100 as it is in Celsius; converting this to an out-of-ten scale would give 3.75/10, labeling it as more cursed than Fahrenheit but less so than Rømer.
|-
| {{w|Rømer scale|Rømer}} || 7.5 || 60 || Fahrenheit precursor with similarly random design || 4/10 || Abbreviated as °Rø, this scale was created by the Danish astronomer {{w|Ole Rømer}} around 1702. Much like Fahrenheit, it originally used the freezing point of ammonium chloride brine as the benchmark for 0°, and the scale is built with factors of 360 in mind with the boiling point of pure water at 60°. Like the Fahrenheit scale, the freezing point of pure water was not originally considered significant by Rømer, but the scale was later updated to give the value of 7.5 at this point.
<center>Celsius = (Rømer - 7.5) × 40/21</center>
<center>Rømer = Celsius × 21/40 + 7.5</center>
The Rømer scale is considered the predecessor of both the Celsius and Fahrenheit scales, because Réaumur was inspired by Rømer's scale, Celsius based his work on Réaumur and Fahrenheit specifically designed his scale with more divisions than Rømer's to reduce the necessity for fractions.
|-
| {{w|Rankine scale|Rankine}} || 491.7 || 671.7 || Fahrenheit, but with 0°F [''sic;'' should be 0°Ra] set to absolute zero || 6/10 || The Rankine scale (°R or °Ra), devised in 1859 by {{w|William Rankine}}, is to Fahrenheit what kelvin is to Celsius, an absolute (rather than a relative) scale. The scale is mostly obsolete, but is still occasionally used in legacy industrial operations where absolute temperature scales are required. It is described as more cursed than the otherwise identical Fahrenheit scale, despite being rooted at a more universal zero point.
<center>Celsius = (Rankine - 491.67) × 5/9</center>
<center>Rankine = (Celsius + 273.15) × 9/5</center>
Another comic, [[2292: Thermometer]], expresses disdain for this scale.
|-
| {{w|Newton scale|Newton}} || 0 || 33-ish || Poorly defined, with reference points like "the hottest water you can hold your hand in" || 7-ish/10 || The famous scientist and mathematician {{w|Isaac Newton}} published this scale in 1701, which was referred to by the the °N symbol. Sadly, the degrees of temperature specified do not correlate exactly with amounts of {{w|heat}}. The cursedness rating (7-ish/10) is a joke about the vagueness of the scale's definition. So, as a linear appproximation:
<center>Celsius = Newton × 100/33</center>
<center>Newton = Celsius × 33/100</center>
Very few scientists other than Newton ever used this scale,{{Actual citation needed}} but it did appear on commercial thermometers around 1758.[https://www.scienceandsociety.co.uk/results.asp?image=10413117&wwwflag=&imagepos=43]
|-
| {{w|Wedgwood scale|Wedgwood}} || –8 || –6.7 || Intended for comparing the melting points of metals, all of which it was very wrong about || 9/10 || Created by the potter {{w|Josiah Wedgwood}} in 1782, the '°W' scale was based on the shrinking of clay when heated above red heat, but was found to be very inconsistent.
<center>Celsius = (Wedgwood + 8) × 100/1.3</center>
<center>Wedgwood = (Celsius × 1.3/100) - 8</center>
The comic has a typo, as the scale is called Wedgwood, without the second 'e'.
|-
| Galen || –4? || 4?? || Runs from –4 (cold) to 4 (hot). 0 is "normal"(?) || 4/–4 || The Greek physician {{w|Galen}} suggested a "neutral" temperature around 180 A.D.,[https://www.loebclassics.com/view/galen-temperaments/2020/pb_LCL546.3.xml] when he was a prominent physician in the {{w|Roman Empire}}. Created by mixing equal parts of boiling water and ice, on either side of this neutral point he described four degrees of heat and four degrees of cold.
<center>Celsius = (Galen × 100 / 8) + 22</center>
<center>Galen = ((Celsius - 22) / 100) × 8</center>
This range from +4 to –4 is humorously used as its rating, implying -100% cursedness. Technically this makes it the least cursed of all the listed scales, but the idea of negative cursedness (or cursedness itself) would be Randall's invention. There is no standard modern abbreviation for Galen's scale.
|-
| {{w|Celsius#History|''Real'' Celsius}} || 100 || 0 || In Anders Celsius's original 1742 specification, bigger numbers are ''colder''; others later flipped it || 10/0 || Most scales' temperatures can be indefinitely large, but have an absolute minimum temperature. By starting at a maximum value and counting down, this scale is indeed cursed, as nearly all possible temperatures through 1.42x1032K, the maximum attainable physical temperature,[https://doi.org/10.4236/jamp.2024.1210198] will be negative in this implementation. The cursedness rating (10/0) is a joke on the scale "flipping" the fixed points of modern Celsius. Division by zero is strictly undefined (see [[2295: Garbage Math]]) and may be interpreted in a number of counter-intuitive ways.
<center>Celsius = 100 - real_Celsius</center>
<center>real_Celsius = 100 - Celsius</center>
The original logic was that zero could be easily calibrated to the height of a {{w|Millimetre of mercury|column of mercury}} at the temperature of boiling water, and further measurements then made of the amount it ''reduced'' in height under cooler conditions. This orientation survives in the historic {{w|Delisle scale}} devised in 1732 by French astronomer {{w|Joseph-Nicolas Delisle}}, which arguably inspired the Celsius scale. The scale originally used by Professor Celsius was changed, to more or less the form already described above, after his death in 1745. Delisle's scale was never reversed.
|-
| [https://physics.stackexchange.com/questions/459851/john-daltons-temperature-scale#459863 Dalton] || 0 || 100 || A nonlinear scale; 0°C and 100°C are 0 and 100 Dalton, but 50°C is 53.9 Dalton || 53.9/50 || {{w|John Dalton}} proposed a logarithmic temperature scale in 1802 during his work on what became {{w|Charles's Law}}. The scale is defined so that absolute zero is at negative infinity, with the exponent chosen to match Celsius at 0 and 100:
<center>Celsius = 273.15 × ''e''(Dalton / 320.55) - 273.15</center>
<center>Dalton = 320.55 × {{w|Natural logarithm|''ln''(}} (Celsius + 273.15) / 273.15 )</center>
There is no standard abbreviation for Dalton's scale. While Dalton temperature is defined for all positive and negative numbers, the nonlinear scale is difficult to work with since the amount of heat represented by a change of one degree Dalton is not constant. Degrees Dalton differs from Celsius by as much as 3.9 degrees between 0 and 100, but diverges much more for more extreme temperatures. The rating (53.9/50) is a joke about the unit, as 53.9 Dalton equates to 50 degrees Celsius — i.e., it could be said to be 107.8% (even more than entirely) cursed.
|-
| °X || 42.9 || 151.4 || '''Title text:''' "In my new scale, °X, 0 is Earths' [''sic''] record lowest surface temperature, 50 is the global average, and 100 is the record highest, with a linear scale between each point and adjustment every year as needed." || Randall has not stated the cursedness of his new scale || The {{w|Lowest temperature recorded on Earth|record lowest surface temperature on Earth}} as of 2024 is –89.2°C (–128.6°F), recorded at the {{w|Vostok Station|Vostok Research Station}} in Antarctica on July 21, 1983.[https://wmo.asu.edu/content/world-lowest-temperature] The average surface temperature as of 2023, the most recent available, is 14.8°C (58.6°F.)[https://climate.copernicus.eu/climate-indicators/temperature] The {{w|Highest temperature recorded on Earth|record highest temperature}} is 56.7°C (134.1°F), recorded on July 10, 1913 at {{w|Furnace Creek, California|Furnace Creek Ranch}} in Death Valley, California.[https://wmo.asu.edu/content/world-highest-temperature]

{{cot|Derivation and graph}}
To break the scale into two linear parts (below and above 14.8°C), we define two separate equations for each range:

1. Below 14.8°C (from –89.2°C to 14.8°C):
* 0 °X corresponds to –89.2°C
* 50 °X corresponds to 14.8°C

We calculate the slope m₁:

<center>m₁ = (50 – 0) / (14.8 – (–89.2)) = 50 / (14.8 + 89.2) = 50 / 104 ≈ 0.48</center>

Now, using the point (14.8°C, 50 °X), we calculate the intercept b₁:

<center>50 = 0.48 × 14.8 + b₁</center>

<center>50 = 7.1 + b₁</center>

<center>b₁ = 50 – 7.1 = 42.9</center>

Thus, the equation for temperatures '''below 14.8°C''' is:

<center>'''X = 0.48 × C + 42.9'''</center>

2. Above 14.8°C (from 14.8°C to 56.7°C):
* 50 °X corresponds to 14.8°C
* 100 °X corresponds to 56.7°C

We calculate the slope m₂:

<center>m₂ = (100 – 50) / (56.7 – 14.8) = 50 / 41.9 ≈ 1.19</center>

Now, using the point (14.8°C, 50 °X), we calculate the intercept b₂:

<center>50 = 1.19 × 14.8 + b₂</center>

<center>50 = 17.6 + b₂</center>

<center>b₂ = 50 – 17.6 = 32.4</center>

Thus, the equation for temperatures '''above 14.8°C''' is:

<center>'''X = 1.19 × C + 32.4'''</center>

;Freezing and boiling points of water

Freezing point of water (0°C): Since 0°C is below 14.8°C, we use the equation X = 0.48 × C + 42.9:

<center>X = 0.48 × 0 + 42.9 = 42.9</center>

So, '''the freezing point is 42.9 °X.'''

Boiling point of water (100°C): Since 100°C is above 14.8°C, we use the equation X = 1.19 × C + 32.4:

<center>X = 1.19 × 100 + 32.4 = 119 + 32.4 = 151.4</center>

So, '''the boiling point is 151.4 °X.'''

[[File:XvsC.png|400px|center]]

See also [[2701: Change in Slope]] for a general discussion of separate linear scales between three points.
{{cob}}
<center>Celsius = (°X - 42.9) / 0.48 if °X < 50.0; or (°X - 32.4) / 1.19 if °X ≥ 50.0</center>
<center>°X = 0.48 × Celsius + 42.9 if Celsius < 14.8; or 1.19 × Celsius + 32.4 if Celsius ≥ 14.8</center>

Due to high temperature records increasing almost every year (and similarly the trend in average temperatures) as a result of {{w|climate change}}, Randall's new °X scale must be re-calibrated each year. While the subsequent °X value being given to everyday benchmark temperatures will vary over time, more extreme values like absolute zero or the {{w|Tungsten#Physical properties|melting point of tungsten}} will shift vastly more.

("Surface" temperatures are measured 1.5 meters above ground inside a shaded shelter, to accurately represent air temperature, because measurements closer to the ground are usually quite different due to sunlight, {{w|albedo}}, and the thermal capacity of soil.)
|}

[[File:Temperature Scales.png|center|600px]]

===Examples===

Here are some various temperatures in the above scales:

{| class=wikitable style="text-align: center;"
! Unit scale
! Typical {{w|room temperature}}
! {{w|Properties of water#Melting point|Freezing point of water}}
! {{w|Boiling point#Boiling point of water with elevation|Boiling point of water}} 
! {{w|Human body temperature}} (range midpoint)
! Recommended {{w|Refrigerator#Temperature zones and ratings|refrigerator temperature}}[https://www.realsimple.com/food-recipes/shopping-storing/food/refrigerator-temperature]
! Recommended {{w|Refrigerator#Freezer|freezer temperature}}[https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/freezing-and-food-safety]
! Typical warm bath temperature[https://www.kohlerwalkinbath.com/blog/everything-you-need-to-know-about-the-ideal-bath-temperature/]
! Typical {{w|Coffee#Brewing|hot coffee}} temperature
|-
| Celsius || 22 °C || 0 °C || 100 °C || 37 °C || 2.5 °C || -18 °C || 39 °C || 77 °C
|-
| Kelvin || 295 K || 273 K || 373 K || 310 K || 276 K || 255 K || 312 K || 350 K
|-
| Fahrenheit || 72 °F || 32 °F || 212 °F || 98.6 °F || 36.5 °F || 0 °F || 102 °F || 171 °F
|-
| Réaumur || 17.6 °Ré || 0 °Ré || 80 °Ré || 29.6 °Ré || 2 °Ré || -14.4 °Ré || 31.2 °Ré || 61.6 °Ré
|-
| Rømer || 19.1 °Rø || 7.5 °Rø || 60 °Rø || 26.9 °Rø || 8.8 °Rø || -2 °Rø || 28 °Rø || 47.9 °Rø
|-
| Rankine || 531 °Ra || 492 °Ra || 672 °Ra || 558 °Ra || 496 °Ra || 459 °Ra || 562 °Ra || 630 °Ra
|-
| Newton || 7.3 °N || 0 °N || 33 °N || 12.2 °N || 0.8 °N || -5.9 °N || 12.9 °N || 25.4 °N
|-
| Wedgwood || -7.71 °W || -8.00 °W || -6.70 °W || -7.52 °W || -7.97 °W || -8.23 °W || -7.49 °W || -7.00 °W
|-
| Galen || 0.00 || -1.76 || 6.24 || 1.20 || -1.56 || -3.20 || 1.36 || 4.40
|-
| ''Real'' Celsius || 78 || 100 || 0 || 63 || 98 || 118 || 61 || 23
|-
| Dalton || 24.8 || 0 || 100 || 40.7 || 2.9 || -21.9 || 42.8 || 79.6
|-
| °X || 59 °X || 43 °X || 151 °X || 76.4 °X || 44.1 °X || 34.3 °X || 78.8 °X || 124 °X
|-
| [[1923: Felsius|Felsius]] (XKCD comic 1923) || 46.8 || 16.0 || 156 || 67.8 || 19.5 || -9.2 || 70.6 || 123.8
|}

==Transcript==

:Temperature Scales

:[A table with five columns, labelled: Unit, water freezing point, water boiling point, notes, cursedness. There are eleven rows below the labels.]

:[Row 1:] Celsius, 0, 100, Used in most of the world, 2/10
:[Row 2:] Kelvin, 273.15, 373.15, 0K is absolute zero, 2/10
:[Row 3:] Fahrenheit, 32, 212, Outdoors in most places is between 0–100, 3/10
:[Row 4:] Réaumur, 0, 80, Like Celsius, but with 80 instead of 100, 3/8
:[Row 5:] Rømer, 7.5, 60, Fahrenheit precursor with similarly random design, 4/10,
:[Row 6:] Rankine, 491.7, 671.7, Fahrenheit, but with 0°F set to absolute zero, 6/10
:[Row 7:] Newton, 0, 33-ish, Poorly defined, with reference points like "the hottest water you can hold your hand in", 7-ish/10
:[Row 8:] Wedgewood, –8, –6.7, Intended for comparing the melting points of metals, all of which it was very wrong about, 9/10
:[Row 9:] Galen, –4?, 4??, Runs from –4 (cold) to 4 (hot). 0 is "normal"(?), 4/–4
:[Row 10:] ''Real'' Celsius, 100, 0, In Anders Celsius's original specification, bigger numbers are ''colder''; others later flipped it, 10/0
:[Row 11:] Dalton, 0, 100, A nonlinear scale; 0°C and 100°C are 0 and 100 Dalton, but 50°C is 53.9 Dalton, 53.9/50

{{comic discussion}}

[[Category:Charts]]
[[Category:Physics]]
[[Category:Science]]

Talk:3001: Temperature Scales

2024-10-23T04:37:08Z

172.71.147.141:

Shouldn't Rankine say "0ºR is set to absolute zero"? {{unsigned ip|172.70.230.29|22:58, 21 October 2024 (UTC)}}
:Yep. [[Special:Contributions/162.158.186.253|162.158.186.253]] 04:38, 22 October 2024 (UTC)

yo,i thought comic 300
0 was anticlimactic so randall would make this one COOL but sadly not
Same. Hope he does something cool for 3072.[[Special:Contributions/172.69.134.225|172.69.134.225]] 23:44, 21 October 2024 (UTC)

really he didn't do anything special for this either? come ON randall if you don't do something cool for comic 3072 i will come to your house personally and yell at you [[User:RadiantRainwing|RadiantRainwing]] ([[User talk:RadiantRainwing|talk]]) 23:57, 21 October 2024 (UTC)

 
What's random about Fahrenheit? (Answer: nothing.) 0F is the freezing point of brine, 100F (or 98.7) is the human body temperature. [[Special:Contributions/172.68.54.65|172.68.54.65]] 00:00, 22 October 2024 (UTC)
:What concentration of brine? (And which specific salt... No, not NaCl, as you might presume but NH4Cl!)
:And body temperature varies a lot ('typically' 36.5–37.5°C or 97.7–99.5°F, though even this range is thought to be too small), across genders, individuals, time of day ''and'' which orifices/surfaces you try to measure it from. (Originally, it was set so that '''90°F''' was to be the 'best guess' of human body temperature. It gradually changed, including via various {{w|Human body temperature#Historical understanding|compounded misunderstandings}} so that the best you can say is that 100°F is arbitrarily ''slightly above'' most afebrile human body temperature measurements.)
:Celsius might be a bit off (arguments about triple-point or STP freezing, etc), but it still has far more physical logic to it. [[Special:Contributions/172.70.160.188|172.70.160.188]] 01:14, 22 October 2024 (UTC)

Sorry, Randall, for my comfort, Fahrenheit is the least cursed. It's the best scale to use for my personal use, especially when hearing the weather report and deciding what to wear outdoors: temp in the 80's - no jacket. temp in 70's - maybe a windbreaker if it's breezy. 60's - sweater weather. 50's - medium weight coat. 40's - winter coat. 30'3 - winter coat with scarf and gloves. 20's - multiple layers. teens - stay indoors. None of the other scales provide such convenient distinctions for my daily life. Kelvin is great for astro physics or super conductivity, but useless for any common uses. Celsius is great for hanging out with the Euro crowd but still not so useful to scale my home thermostat. I judge Fahrenheit as 1.0 for cursedness. [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 14:19, 22 October 2024 (UTC)
:I conveniently use Celsius in tens, also. Negative °C: Cold; 0-10°C: Nippy; 10-20°C: Generally pleasant; 20-30°C: Too warm to exert oneself; 30°C+: ''Definitely'' too warm. [[Special:Contributions/172.70.86.205|172.70.86.205]] 15:24, 22 October 2024 (UTC)

Personally, I'm most disappointed that {{w|Delisle scale}} was not represented... [[Special:Contributions/172.70.160.188|172.70.160.188]] 01:14, 22 October 2024 (UTC)
: I was so hoping for a {{w|Planck temperature}} quip. Like: "Water freezing point: 0; Water boiling point: 0; Notes: 1 = highest possible temperature (1.4E32K) where thermal radiation creates black holes; Cursedness: 0/0" [[Special:Contributions/162.158.164.184|162.158.164.184]] 01:27, 22 October 2024 (UTC)
:: Same here. Freezing is 0.000000000000000000000000000001928 and boiling is 0.0000000000000000000000000000026338. [[User:DanielLC|DanielLC]] ([[User talk:DanielLC|talk]]) 03:38, 22 October 2024 (UTC)
::: Wow, those are even smaller than the IEEE floating point representations of 1-1.0/3*3! [[Special:Contributions/162.158.90.109|162.158.90.109]] 03:59, 22 October 2024 (UTC)

I guess I was wrong in my comment on the last comic. sigh. -[[User:Psychoticpotato|P?sych??otic?pot??at???o ]] ([[User talk:Psychoticpotato|talk]]) 01:16, 22 October 2024 (UTC)

It's actually spelled {{w|Wedgwood scale}}, not Wedgewood. [[User:Wilh3lm|Wilh3lm]] ([[User talk:Wilh3lm|talk]]) 01:17, 22 October 2024 (UTC)

I still call the modern version of the "Celsius" scale "centigrade", but if people start nitpicking, I'm happy to switch to "Carolus" to avoid ambiguity. For some reason that tends to annoy people more though. [[Special:Contributions/172.68.22.191|172.68.22.191]] 01:32, 22 October 2024 (UTC)

Every temperature scale is equally "random" as every other scale. People always say that Celsius is so much better because it's defined by the phase changes of water. Okay, cool...why should THAT of all things be what we use as the base for a system of temperature measurement? And, who cares? I'm a ''Homo sapiens'', not a water molecule. If anything we should use the freezing and melting points of humans as our two reference points for temperature (which, I must say, Fahrenheit approximates better than Celsius, assuming 0 and 100 are your points "A" and "B"). [[User:Pie Guy|Pie Guy]] ([[User talk:Pie Guy|talk]]) 03:42, 22 October 2024 (UTC)
: Every temperature scale is arbitrary, but since boiling and freezing water is a thing humans have a lot of experience with it makes sense to use that as the reference point. At least it makes more sense than whatever the coldest recorded temperature in Fahrenheit's home town was, because he didn't like negative numbers [[Special:Contributions/172.70.250.23|172.70.250.23]] 03:56, 22 October 2024 (UTC)
::Planck temperature (as above) is probably the least arbitrary, and some would say it is to some extent free from arbitrariness. However, it's completely impractical for everyday use (as above.) [[Special:Contributions/172.69.34.138|172.69.34.138]] 04:31, 22 October 2024 (UTC)
:::Do the physics of black holes or neutron stars involve Planck temperatures greater than 0.0000001? [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 07:23, 22 October 2024 (UTC)
::::Chat Gippity told me:

:::::Black holes and neutron stars do not typically involve temperatures reaching the Planck scale. While both objects exhibit extreme physical conditions, their temperatures are far below the Planck temperature, even though they can be incredibly high compared to everyday phenomena.

::::: - **Neutron stars** have surface temperatures in the range of millions of Kelvin, and the core can reach even higher, possibly up to a few billion Kelvin. These temperatures are still vastly lower than the Planck temperature.

::::: - **Black holes**, especially the smaller ones, can emit Hawking radiation, with temperatures inversely proportional to their mass. However, the temperature of even a very small black hole is still far below the Planck temperature. Hawking radiation is not expected to reach temperatures close to the Planck scale under normal circumstances.

::::: The Planck temperature (TP=1) represents an energy scale so extreme that no known physical models, including those describing black holes and neutron stars, operate near or above this threshold. Temperatures reaching **0.0000001 TP** (or 1.416 × 10^26 K) would still be beyond current observational and theoretical frameworks related to these cosmic objects. A quantum theory of gravity would be required to describe physics at or near the Planck temperature, which remains speculative and is far beyond the conditions found in black holes or neutron stars.

::::[[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 08:46, 22 October 2024 (UTC)

If the °X scale is based on the temperatures of Earth from all time (for some definition of "Earth"), then the scale is very hard to define and highly impractical. The earth appears to have gotten to more than 2,300 Kelvin (hot enough to melt steel and platinum and to boil lead) and while I can't find any sources for the lowest temperature, I imagine it is lower than -100°C. The recorded minimum, maximum and average temperatures appear to be around -89.2 °C, 56.7 °C and 15 °C respectively. This would make the scale somewhat useful, but this would make typical values between 41 °X (cold winter's day) and 68 °X (hot summers day) which I think is pretty cursed. I recommend the clearly superior °Y, based around average temp at 0 °Y, low at -100 °Y and high at 100 °Y. These would be measured by the yearly high, low and mean temperatures averaged per person. Then saying "It's 2 times colder than yesterday" would have some reasonable meaning. --[[Special:Contributions/198.41.236.147|198.41.236.147]] 04:01, 22 October 2024 (UTC)
:"''Record'' ... surface temperature" implies it was recorded. [[Special:Contributions/172.68.22.9|172.68.22.9]] 04:08, 22 October 2024 (UTC)

How do you all feel about adding an additional column for room temperature 22C/72F?
{| class=wikitable style="text-align:right;"
! scope="col" | Unit
! scope="col" | Room temperature
|-
| Celsius || 22
|-
| Kelvin || 295
|-
| Fahrenheit || 72
|-
| Réaumur || 18
|-
| Rømer || 18
|-
| Rankine || 531
|-
| Newton || 7
|-
| Wedgwood || -7
|-
| Galen || 0
|-
| ''Real'' Celsius || 78
|-
| °X || 58
|}

Or 0.00000000000000000000000000000208 °Planck, lol. [[Special:Contributions/108.162.245.211|108.162.245.211]] 05:36, 22 October 2024 (UTC)
:I feel like decigalens would be the most practical unit. Who's with me? [[Special:Contributions/162.158.186.5|162.158.186.5]] 06:20, 22 October 2024 (UTC)
::It's interesting; calculating the equilibrium temperature (with 2.05 and 4.24 being used for the heat capacities of ice and boiling water) gives 67... If I use water that's about to freeze and steam, I get 31. [[Special:Contributions/172.69.0.178|172.69.0.178]] 07:59, 22 October 2024 (UTC)
:::Would you please explain in more detail? [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 09:03, 22 October 2024 (UTC)
:::: The equilibrium temperature of a mixture (?) of equal quantities of ice at 0 C and water at 100 C (with the heat capacities 2.05 and 4.24) is 67 C; if I use the data for water at 0 C and steam, I get 31 C. Additionally, if I use equal volumes, I get 68 (which isn't much different.) [[Special:Contributions/172.69.0.178|172.69.0.178]] 17:15, 22 October 2024 (UTC)

Question regarding the X scale - when it‘s defined by *three* (somewhat, implying average is real and not just calculated by (max-min)/2)) independent points, how will linearity be achieved? [[Special:Contributions/162.158.155.76|162.158.155.76]] 05:43, 22 October 2024 (UTC)
[[File:Explanation length.png|right|thumb|Or click "[Expand]" in the bottom right table cell Derivation.]]
:Please see [[2701: Change in Slope]]. [[Special:Contributions/172.70.206.179|172.70.206.179]] 05:50, 22 October 2024 (UTC)
:Sure, "a linear scale between each point":
[[File:XvsC.png|thumb|left|Here you go. [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 06:33, 22 October 2024 (UTC)]]
{{clear}}

The reference for the average surface temperature, https://www.space.com/17816-earth-temperature.html, suggests it has increased above 15°C. What value should we use in late 2024? [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 07:30, 22 October 2024 (UTC)
:The [https://wmo.int/media/news/earth-experiences-warmest-day-recent-history World Meteorological Organization], [https://www.carbonbrief.org/state-of-the-climate-2024-now-very-likely-to-be-warmest-year-on-record/ Carbon Brief], and [https://climate.copernicus.eu/new-record-daily-global-average-temperature-reached-july-2024 Copernicus Climate Change Service] suggest 17.16°C. [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 07:42, 22 October 2024 (UTC)
::Updated water temperatures, Derivation, and graph. So we've already had more than the +2°C warming we were trying to avoid in 2019? [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 08:05, 22 October 2024 (UTC)

Regarding [https://www.explainxkcd.com/wiki/index.php?title=3001%3A_Temperature_Scales&type=revision&diff=353635&oldid=353632], are the average surface temperatures from the sources supposed to be yearly or overall averages? [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 09:06, 22 October 2024 (UTC)

where is the interactive epic 3000 comic we should've gotten? This one's cool but 1000 seemed to have more effort in it and 2000 was at least tangetially related. Does Randall just not like making these anymore and is only making more comics as a business? [[Special:Contributions/108.162.238.185|108.162.238.185]] 12:14, 22 October 2024 (UTC)
:The comic is free on the website and it doesn't have ads; although the comic is part of his "brand" there are many more profitable things he could be doing with his time, and yet he continues to update it every Monday, Wednesday, and Friday. I just don't like the idea of claiming that a creative person "should" produce any particular thing to satisfy their fans. He's a busy guy! Maybe he's working on a book, or a Scientific American article, or a TV show. He's under no obligation to give us anything, and maybe one day he'll stop making xkcd altogether; that's his choice. Sorry to single you out; I know a lot of people feel the same way as you do, but to me it doesn't make sense. He's not a content machine--he's a guy who started posting sketches on the internet. [[User:Dextrous Fred|Dextrous Fred]] ([[User talk:Dextrous Fred|talk]]) 15:23, 22 October 2024 (UTC)

Sorry if I sounded overly brash, I wasn't trying to imply "wahhh no special entry wahhh", I was just wondering if Randall still likes to make these or if he doesn't, mainly because he just didn't do anything special, which feels like he just didn't care. I wasn't trying to imply Randall should just do it for the fans[[Special:Contributions/108.162.238.80|108.162.238.80]] 17:52, 22 October 2024 (UTC)

Is this the first list-style comic where every single entry is real? (Usually he has several joke entries.) [[Special:Contributions/172.70.114.182|172.70.114.182]] 14:26, 22 October 2024 (UTC)

2993: Ingredients

2024-10-03T15:16:18Z

172.71.147.141:

{{comic
| number = 2993
| date = October 2, 2024
| title = Ingredients
| image = ingredients_2x.png
| imagesize = 417x473px
| noexpand = true
| titletext = Add main-belt asteroids to taste.
}}

==Explanation==
{{incomplete|Created by a THE FIVE BEST EXPLAINXKCD USERS COMBINED INTO ONE - Table of each moons with its special ingredients as well as the volume and surface area, and compare the combined volume and combined surface area to that of Mars (also check both the actual surface area of the five as well as the surface area of a sphere with the total moons volume, which would be a much smaller surface area than of the five moons sum of surface area... Do NOT delete this tag too soon.}}
This comic jokes that it is possible (and perhaps intended) to use the five largest moons in the outer solar system (the Galilean moons + Titan) as ingredients, to create a “better” planet, that has the “coolest features”. Apparently, though, Randall couldn't actually think of anything cool that Ganymede and Callisto could contribute, so these have just been used as 'filler'.

Note that Earth's moon is the fifth-largest moon of the solar system overall (Europa is the sixth), so would have been included had "outer solar system" not been specified.

The title text takes it further, treating asteroids as a “to-taste” ingredient in this “recipe”, treating it more like preparing a food dish, rather than making a new Mars sized planet.

There are a number of science fiction works that posit that advanced alien civilizations left puzzles in the solar system for future humans to solve. [Examples needed]

==Transcript==
:[A planet is shown with several different features like oceans and large lakes as well as and craters. It seems like the continent is fused together from five different segments, with cracks between where there is either ocean or rivers. There are four labels above the planet with lines going down to different areas of the planet, but not necessarily pointing to any particular part on the surface, but rather to the entire planet:]
:Sulfur chemistry from Io
:Cool oceans from Europa
:Hydrocarbons from Titan
:Ganymede and Callisto (filler)

:[Caption beneath the panel:]
:Scientists now think the five biggest outer solar system moons are actually just ingredients; we're supposed to combine them to create a single Mars-sized planet that's cooler than any of them.

{{comic discussion}}

[[Category:Space]]
[[Category:Food]]

Talk:2941: Cell Organelles

2024-06-05T03:21:18Z

172.71.147.141:

I'm a little disappointed there isn't a continuous endoplasmic reticulum with a zigzag in it.
Rogue mathematician away [[Special:Contributions/172.71.154.77|172.71.154.77]] 19:20, 3 June 2024 (UTC)

Sorry about the edit conflicts, attempting to fix.... [[Special:Contributions/108.162.245.237|108.162.245.237]] 20:12, 3 June 2024 (UTC)

Re [https://www.explainxkcd.com/wiki/index.php?title=2941:_Cell_Organelles&diff=343629&oldid=343628] is LLM use forbidden? I recall we have several ChatGPT-authored explanations, and had an ongoing discussion back when it was new. In any case, I've proofread and vouch for it, so I'm replacing the text. I encourage anyone who's bothered by it to paraphrase instead of delete. [[Special:Contributions/108.162.245.237|108.162.245.237]] 21:22, 3 June 2024 (UTC)

:If you've got the time to check AI-generated content properly and agree that it's what ''you'' would have written, you've got time to write it from scratch exactly how you'd have written it. And you get dangerously close to just putting in AI-content without checking at all, which right now is remains foolhardy.
:But, most of all, anything anyone submits can be changed by anyone else, and I don't know who picked up on it being AI and dealt with it the way they did, but only consensus can truly resolve where any attempt to impose an edit leads. [[Special:Contributions/162.158.74.119|162.158.74.119]] 22:36, 3 June 2024 (UTC)

::I almost completely agree with you for Wikipedia (I'd just change 'would' to 'could') and similar wikis, but it's undeniable that ExplainXkcd is different in some very substantial and obvious ways, many of which bear on whether to utilize AI. In particular, I would accept pretty much anything that helps explain the comic whether authored by human, machine, animal, or alien, but not hesitate for a second to, as the text below the Summary text input box says, edit it "mercilessly" whether I thought it was LLM-generated or not. But I wouldn't delete an even barely serviceable explanation ''just'' because I thought it came from an LLM, even if it was objectively low quality. I would try to improve it, which almost never means starting over from scratch. I'm not sure I believe the same is true for humans, who often insert, e.g., vandalism, trolling, or extremely undue and/or fringe topic passages. If an LLM is doing that, there's probably a human behind it. [[Special:Contributions/108.162.245.17|108.162.245.17]] 00:21, 4 June 2024 (UTC)

:Both the paragraphs and the table have been edited far enough from what ChatGPT pretty obviously came up with (almost all of which I would say merit inclusion unaltered, [https://www.explainxkcd.com/wiki/index.php?title=2941:_Cell_Organelles&diff=343604&oldid=343601 looking at the initial edits; although there is evidence that the LLM output was copyedited and wikilinked in a way that it would probably not do,] i.e., we use the {{tl|w}} template here which is not at all a Mediawiki standard, the Wikimedia wikis having a different form <nowiki>[[w:...]]</nowiki>) so that whatever deleterious LLM contamination they had has surely been beat out of them at this stage. Perhaps the GenAI deletionist is trying to encourage others to not fall prey to reliance on LLMs? A worthy goal, but I agree paraphrasing is far superior. [[Special:Contributions/172.69.34.180|172.69.34.180]] 01:57, 4 June 2024 (UTC)

Re: the chloroplasts explanation: how do we know that this is an animal cell? (Would be good to say why...) -- [[User:Dtgriscom|Dtgriscom]] ([[User talk:Dtgriscom|talk]]) 22:18, 3 June 2024 (UTC)
:The cell has a membrane instead of a wall. [[Special:Contributions/162.158.90.199|162.158.90.199]] 22:24, 3 June 2024 (UTC)
::No, that’s human skin. [[User:Usb-rave|Usb-rave]] ([[User talk:Usb-rave|talk]]) 00:48, 4 June 2024 (UTC)
:: There are lots of organisms out there that have plastids (chloroplasts) and do not have cell walls ... that, in fact, do not fit the common conception of either 'plant' or 'animal'. Euglena might still be the most famous example - Euglena is more closely related to the protozoa that cause trypanosomiasis than to either plants or animals - but there are many others, and it's a deep rabbit hole. [[Special:Contributions/162.158.41.117|162.158.41.117]] 18:52, 4 June 2024 (UTC)
:: And speaking of "lucky to have them", did you know that plastids are [https://en.wikipedia.org/wiki/Kleptoplasty worth stealing]? [[Special:Contributions/172.68.23.200|172.68.23.200]] 21:14, 4 June 2024 (UTC)

:::Yeah, the rule of thumb is of course a generalization worthy of chemistry "rules" -- the {{w|bone cell}} being perhaps the most obvious uncategorizable corner case of several. [[Special:Contributions/172.71.150.236|172.71.150.236]] 02:12, 4 June 2024 (UTC)

Why does Golgi look like an alien, he's so little and cute. Wtf. [[User:Psychoticpotato|Psychoticpotato]] ([[User talk:Psychoticpotato|talk]]) 23:11, 3 June 2024 (UTC)

:You know what I would like to see from AI? A tiny white Grey Golgi alien working in the cytoplasm to build his apparatus. Please see below. [[Special:Contributions/172.71.147.106|172.71.147.106]] 03:50, 4 June 2024 (UTC)

Should 2732: Bursa of Fabricius be referenced? It feels like the Golgi Apparatus is making a similar joke, if somewhat inverted. [[User:Dkfenger|Dkfenger]] ([[User talk:Dkfenger|talk]]) 01:19, 4 June 2024 (UTC)

To me, 'Drain plug' is an engine oil-drain plug. Yes it is a bolt, rarely used in biological systems. But a cell and an engine are normally full of fluid, while plumbing sinks are normally empty. --[[User:PRR|PRR]] ([[User talk:PRR|talk]]) 02:10, 4 June 2024 (UTC)
:To me it's about as often something you would find in a kitchen or bathroom sink, especially if the plumbing was from the 1970s or earlier. Honestly I'm too young to know when sink plugs fell out of favor to levers. In any case, an actual hole in the cell membrane is almost always a potentially mortal wound, and few cells have any means of repairing all but the smallest tears. [[Special:Contributions/172.70.207.197|172.70.207.197]] 02:47, 4 June 2024 (UTC)

Hello there! 👋 I think you guys mixed up midichlorian and mitochondria explanations. 👋 You surely will want to fix that. 👋 Also, you want to make me a sandwich. [[Special:Contributions/172.70.85.177|172.70.85.177]] 05:13, 4 June 2024 (UTC)
:LGTM. [[Special:Contributions/172.71.146.218|172.71.146.218]] 09:29, 4 June 2024 (UTC)

I'm a little bit disappointed that there's no Sulawesi hidden in there. This is the sort of comci you'd expect it in. [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 06:48, 4 June 2024 (UTC)
: I'm disappointed that, alongside the drain plug, there isn't a pain drug.[[Special:Contributions/172.69.195.183|172.69.195.183]] 12:52, 4 June 2024 (UTC)
:: It would have had to have been a generic. [[Special:Contributions/172.71.147.141|172.71.147.141]] 03:21, 5 June 2024 (UTC)

I dislike that this table is in alphabetical order instead of the top-down order they were meant to be read.[[Special:Contributions/172.70.231.39|172.70.231.39]] 10:08, 4 June 2024 (UTC)
:"Fixed." Click the column heading to return to alphabetical order. [[Special:Contributions/162.158.186.196|162.158.186.196]] 17:19, 4 June 2024 (UTC)

I'm going to fail my Biology exam tomorrow because of this :( ([[User talk:SectorCorruptor|talk]]) 11:52, 4 June 2024 (UTC)

=== Golgi by AI art contest ===

Survey questions: (1) Which of these do you like the best? https://ibb.co/album/68tCSn Can you do better?

(2) Does anyone know how to make AI animations like those? [[Special:Contributions/172.71.142.181|172.71.142.181]] 03:49, 4 June 2024 (UTC)

== Nucleolus ==

Wouldn't "Nucleololus" be a better continuation to "Nucleus" and "Nucleolus", with each term getting one more "ol" between "e" and the second "u"? [[Special:Contributions/172.71.222.50|172.71.222.50]] 08:04, 4 June 2024 (UTC)

Talk:2659: Unreliable Connection

2023-03-06T23:51:34Z

172.71.147.141:

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1692: Man Page

2023-02-09T04:26:06Z

172.71.147.141:

{{comic
| number = 1692
| date = June 10, 2016
| title = Man Page
| image = man_page.png
| titletext = For even more info, see blarbl(2)(3) and birb(3ahhaha I'm kidding, just Google it like a normal person.
}}

==Explanation==
This comic shows a {{w|Unix}} manual page, i.e. a ''{{w|man page}}'' (hence the title), for a fictional program called "[http://www.urbandictionary.com/define.php?term=blerp blerp]". Unix man pages are meant to provide a brief reference on the usage of a command, not extended explanations with tutorials as may be found in many hardcopy product manuals. Unfortunately, some Unix commands tend to be very bloated and include lots of optional behavior that is often irrelevant to the original intent of the command and can be done much more easily using shell features like piping and redirection, and thus the manpage grows to explain all of the features. This example exaggerates the obscurity and terseness found in many man pages, making fun of the typical style of the genre.

It follows the prescribed format for a man page, with the following sections:
*Command Name: self-explanatory
*Synopsis: a synopsis of the valid command line formats
*Description: a summary of the purpose and operation of the command
*Options: detailed description of all the available command line arguments
*See Also: references to other man pages with relevance
*Bug Reports: contact details for the support group (if any)
*Copyright: details of the ownership and rights status of the man page (not the program)

For comic effect, most of this particular man page is not meaningful, and sometimes doesn't obey the expected syntax.

The Synopsis section is supposed to be in a {{w|Regular Expression|regex}}-like language called {{w|Wirth Syntax Notation}}, with structures like

*{<list of valid alternatives>}, e.g. blerp {A,B,C}
*[<optional element>], e.g. blerp [-o [<output file>]]
*<something>... meaning repeat <something> as many times as you need

But the two Synopsis lines given do not have valid Wirth syntax; they randomly mix objects and syntactic characters, and the brackets and braces are not properly nested or paired.

The Description section provides an unhelpful summary that could apply to almost any Unix command. Processing input files (or output of other commands in a pipeline) is a generic function for Unix shell tools, as is specifying their behaviour with command line arguments, environment variables and flags. The text leaves to the reader's imagination what the program actually ''does'', and what behavior the various options modify, which gives maximum scope for humorous possibilities.

The options are in conventional alphabetical order, except that lower case is placed before upper case, and an em-dash is inserted between b and c.

{{w|Command-line_interface#Command-line_option|Command-line options}}, also known as flags, are typed after the program's name to change how the program runs. For example, a user of ''blerp'' might type:

<code>blerp -a -d -t -p "AVIGNON"</code>

According to the man page, this would run blerp in attack mode, piping its output to DEBUG.EXE, with tumble dry, and the true Pope set to "AVIGNON". In most cases, any number of flags can be used in any order, and flags can be followed by argument (such as "AVIGNON" in this example).

For a walkthrough of all possible flags see the '''[[#Table of flags|table of flags]]''' below.

Below the flags there is a ''see also'' list with other ludicrous program names (blirb, [http://www.urbandictionary.com/define.php?term=Blarb blarb] and [http://www.urbandictionary.com/define.php?term=Blorp blorp]), each followed by a number in parentheses. This is a common way to refer to a command in Unix environments, where the number denotes the documentation section the program is found in. This serves to disambiguate man pages with the same name, in this instance those for the blerp command (section 1, "General commands") and the blerp() C library function (section 3, "C library functions").

It is unknown which section the man page in this comic resides in. It looks like it could be in section 1, "General commands", which would make it self-referential. Section numbers only go up to 8, so blarb(51) is not a valid section number. The last blorp(501)(c)(3) is not a valid section number either, it is however a slightly covert reference to {{w|501(c)_organization#501.28c.29.283.29|501(c)(3)}} which is an organization that is {{w|Tax exemption|tax-exempt}}.

Then follows a bug report site. www.inaturalist.org is a site working to extend biological research, and the exact address given, http://www.inaturalist.org/taxa/47744-Hemiptera, points to the same page as http://www.inaturalist.org/taxa/Hemiptera. {{w|Hemiptera}} is the order classifying ''true bugs'', making it a good place to report any biological bugs discovered while running a program (Like the bees found without using -b.) Insects got into some early computers, causing them to malfunction, and hence computer malfunctions are often called "bugs".

Finally there is a "{{w|copyright}}" line which references several variously open-source content licenses, which is a recurring theme on xkcd (see [[225: Open Source]]). For instance, GPL references {{w|GNU General Public License}} and the (2) and (3+) refers to {{w|GNU_General_Public_License#Version_2|GPL 2}} and {{w|GNU_General_Public_License#Version_3|GPL 3 or higher}}. ''CC'' refers to {{w|creative commons}} where ''BY'' is the {{w|Creative_Commons_license#Types_of_licenses|type of license}}, ''5.0'' refers to the attribution and ''RV 41.0'' refers to revision 41.0. However there were no higher attribution than [https://creativecommons.org/licenses/by/4.0/legalcode 4.0] at the time of this comic's release. xkcd is released under [http://creativecommons.org/licenses/by-nc/2.5/ CC BY-NC 2.5] as can be seen at the bottom of the {{xkcd}}  homepage. A few comics have been released under the [[:Category:CC-BY-SA comics|CC-BY-SA license]] or [http://creativecommons.org/licenses/by-sa/3.0/ 3.0]. BSD refers to {{w|BSD licenses}}, another [[:Category:BSD|recurring theme]] in xkcd. "Like Gecko" is a reference to a web browser user-agent string; modern user-agent strings include a [http://webaim.org/blog/user-agent-string-history/ lot of text designed] to allow browsers to masquerade as different browsers/renderers, and "(like Gecko)" is the standard text for a browser that wants to be treated as if it were {{w|Gecko (software)|Gecko}} while admitting, if you look closely, that it isn't really Gecko. This copyright line, which includes a lot of mashed-together text that might appear to match any of several different licenses, resembles a {{w|user agent}} string.

"Or best offer" is usually seen on a notice of a private sale, where it proclaims the intent to be flexible on asking price in the hope of expediting the sale, with a suggestion that the seller will sell to the highest bidder even if the offer is nowhere near the asking price. In the context of the comic, it suggest that the rights for the program are available for purchase by anyone who makes the "best" offer. Since the other licenses listed would allow free usage without incurring any royalty charge, it would be pointless to buy the rights to this program. It is possible to revoke the other licenses though. Perhaps the program's creator is suggesting the rights could be given to someone making him a different sort of offer, perhaps romantic or sexual?

In the title text there is a list with even more info, again with silly names like [http://blarbl.blogspot.dk/ blarbl] and [http://www.urbandictionary.com/define.php?term=birb birb]. Again there are section numbers. While writing about birb, and without bothering to close the brackets around (3), the writer breaks off to laugh at the reader, telling them that he is kidding and suggesting that they ''just Google it like a normal person''. The implication is that anyone trying to pick through a man page to find out what a program does is going the long way round, when it's much simpler to get Google to tell you.

Man pages were part of the subject of [[293: RTFM]], [[912: Manual Override]] and [[1343: Manuals]] and were mentioned in [[434: xkcd Goes to the Airport]] and [[456: Cautionary]].

===Table of flags===
*There are 28 'defined' flags.
**Only these five letters are not used: l, m, w, x, z.
**j and k are used together as jk.
**The following seven capital letters are used: D, I, O, R, S, U, V.
***That makes it one capital letter for every lower case letter that is not used by itself.
**Finally the em dash "—" is used as the only non-letter character. Also the only that breaks the strict alphabetical sorting of the list, with lower case before upper case letters.
**As well as the general expansion of flag-use 'definitions', -f is explicitly featured in the first usage example of the Synopsis. See below.
**Additionally, either "-{}" or "- {}" is featured in the Synopsis's second usage example. This could indicate a flag of further type (an ill-defined set of further possibilities or ''literally'' a curly-bracket pair) or else specifies STDIN as a possible file input (and ''then'' ill-defined/curly-bracketted continuations of the parameter-listing).
{| class="wikitable"
!Flag!!Description!!Explanation
|-
| -a||ATTACK MODE||This sounds like a command for a robot or something similar. Strange for a command line program. Possibly this is designed to break something? Sounds as if you have to ''really'' know what you're doing to use this option. Could also be a reference to Yu-Gi-Oh or other similar games where a card can be played in "Attack Mode".
|-
| -b||SUPPRESS BEES||Nonsensical option. This is a word play, meaning either to suppress {{w|Bee|Bees}} (the insects) or the letter '''B'''. A possible implication is that running the program without this flag would somehow result in the user being attacked by bees. This is also a possible {{w|Discworld}} reference, as the ''{{W|Hex_(Discworld)#Structure_and_technology|long-term storage}}'' of the only recurring computer in the series, ''{{w|Hex (Discworld)|Hex}}'', is composed of a beehive. (Note that the actual computer runs on ants.) Another explanation is that there will be smoke (perhaps {{w|magic smoke}}?), which is used by beekeepers to suppress bees.
|-
| -—||FLAGS USE EM DASHES||Command line options (flags) typically use {{w|Hyphen|hyphens}} (short horizontal lines largely used within words). {{w|Dash#Em_dash|Em dashes}} (longer, with the same length as the letter "m") can't always be easily typed into a command line interface, so by invoking ''blerp'' with this flag you are intentionally making things difficult for yourself.

This may be a play on how a lot of commands accept both single-dash options, like -h for help, as well as double-dash options like --help also for help. In word processors, a double-dash (--) is often replaced with the longer em dash (—), making them kind of synonymous.

Also implies a paradox where if flags were to use em dashes, this flag would be invalid.
|-
| -c||COUNT NUMBER OF ARGUMENTS||Most likely not useful, but the only function of ''blerp'' whose behaviour is at all well defined, although there is no indication whether it would count duplicate flags or only distinct ones.
|-
| -d||PIPES OUTPUT TO DEBUG.EXE||{{w|DEBUG.EXE}} is the old 16-bit debugger that came with MS-DOS. On a Unix system it is much more likely that one would use the {{w|GNU Debugger}} (GDB). A debugger is usually called by calling the debugger with the program (or script) to be debugged as parameter.
{{w|Pipeline (Unix)|Piping}} in Unix means that the output of one program serves as input for another program.
|-
| -D||DEPRECATED||Many programs contain legacy options to avoid breaking scripts that use them. While the option should still work, the documentation is changed to say "deprecated" to discourage further use. Eventually such options usually get removed. (However, given the nature of this comic, it's likely that -D has always stood for "deprecated".)
|-
| -e||EXECUTE SOMETHING||Vague. Also a possible pun on a kill-switch.
|-
| -f||FUN MODE||Strange and slightly ominous, given some of the other options. How does the program know what the user would consider fun? Perhaps ''blerp'' is sentient, and has its own concept of "fun". See under -O.
The presence of an -f and then "FLAGS" in the usage Synopsis suggests that this flag can be used to flag that ''subsequent'' command flags are explicitly under the FUN MODE context, but with nothing to prevent -f (also?) being a standalone flag in the general ARGS (argument options, including flag parameters) ''or'' being further included in such a FUN MODE's hierarchical list of flags. This is just a further ambiguity to the Synopsis format, where it is often explicitly expanded into separate interpretations where the program has a complex but defined-in expectation of how to deal with such varied parsing possibilities.
|-
| -g||USE GOOGLE||As an actual program flag, a bit hackjob-ish, but it is possible it is telling the user to use Google to find out what this tag does. Or, the program might actually use Google functionality (e.g. a code library online) or even simply the search mask to achieve the filtering it is supposed to do. The fact that this is optional suggests that there is also a 'native' implementation that does not use Google.
Possible reference to the title text, which could mean that the title text is telling the user to use this flag.
|-
| -h||CHECK WHETHER INPUT HALTS||The {{w|Halting problem}} is the problem of determining, from a description of an arbitrary computer program and an input, whether the program will finish running or continue to run forever. {{w|Alan Turing}} proved in 1936 that a general algorithm to solve the halting problem for all possible program-input pairs cannot exist. Halting problem also featured in the comic [[1266: Halting Problem]].

Many Unix and Linux commands reserve -h for help, so using it for a different function is non-standard. The ''shutdown'' command is a real example of an exception: it uses -h to cause the computer to halt.
|-
| -i||IGNORE CASE (LOWER)||Usually, ignoring case means that a program will run without differentiating between upper- and lowercase. This flag suggests that blerp will run ignoring all the lowercase characters completely, or ignoring all the uppercase characters with the next flag "-I". Alternatively it will ignore the case of all lower case characters, but not upper case ones. Or perhaps this option makes the program ignore the case of flags like -i and -I...
|-
| -I||IGNORE CASE (UPPER)||See above. Also possible that all text is converted to upper case, or that upper-case requirements only are ignored.
|-
| -jk||KIDDING||A common acronym for [http://www.urbandictionary.com/define.php?term=jk Just Kidding], not usually a program flag! Also note that standard behavior of Unix command line options is that a single "-" can be followed by multiple one-letter options, making -jk equivalent to -j -k. Perhaps this is a reference to the -WhatIf flag provided by many programs written in {{w|powershell}}. Some UNIX programs do offer a "simulation mode" before important, irreversible operations, such as the "-n" switch of mke2fs.
|-
| -n||BEHAVIOR NOT DEFINED||Who would ever knowingly run a program, knowing that {{w|Nondeterministic programming|its behaviour was non-deterministic or random}}? Doing such a thing seems potentially sinister. (Possible debug/unstable feature flag.)
|-
| -o||OVERWRITE||Standard program flag, usually meaning that the program will overwrite a file rather than make a new one when data is output. But the text does not indicate ''what'' the program will overwrite, it could be anything. May work strangely with -d.
|-
| -O||OPPOSITE DAY||Strange flag, a reference to {{w|Opposite Day}}. Perhaps indicates that it would make all other flags have the opposite effects as usual. If so, a lot of strange things would happen, especially with -b, -e, -f, -jk, -O, -S, and -y. On the other hand, it may simply indicate that absent flags are treated as if they were present and vice versa.
|-
| -p||SET TRUE POPE; ACCEPTS "ROME" OR "AVIGNON"||This refers to a {{w|Western_Schism|historical schism}} in the {{w|Catholic Church}}. In the 14th century, the Pope briefly ruled from Avignon, France, instead of Rome. After the Papacy was returned to Rome in 1377, the Church split (the so-called Western Schism) as not everyone accepted the move or the authority of the Pope who ordered it. This flag apparently allows the user to select a preferred Pope. A possible feature request for ''blerp'' would be to allow "PISA". It is the second time this week that Popes have been mentioned, last time was two comics before in [[1690: Time-Tracking Software]] regarding the Pope's sexual activity.
|-
| -q||QUIET MODE; OUTPUT IS PRINTED TO STDOUT INSTEAD OF BEING SPOKEN ALOUD||In most cases, a program will output basic information to the console, and running it in quiet mode will make it run without outputting anything. Blerp, on the other hand, apparently outputs information through audio, and the quiet flag causes it to run like a normal program. "STDOUT" is short for "standard output".
|-
| -r||RANDOMIZE ARGUMENTS||Pointless and possibly damaging. Presumably the randomization takes the form of any flag randomly causing the behavior of another. This would perhaps be similar in effect to the -n flag.
|-
| -R||RUN RECURSIVELY ON <nowiki>http://*</nowiki>||The star (*) symbol is often used as a wildcard to match any string of characters. "<nowiki>http://*</nowiki>" suggests that blerp will be run recursively on every (unsecured) webpage on the internet. Programming requirements that might make this a valid thing to want to do are ominous.
|-
| -s||FOLLOW SYMBOLIC LINKS SYMBOLICALLY||A {{w|symbolic link}} is a filesystem feature that allows the creation of "fake" files which when accessed redirect to another file path. Many commands offer an option to follow filesystem links and operate on the actual file rather than the fake pointer; this option however seems to suggest that it will only politely pretend to do so.
|-
| -S||STEALTH MODE||Similar to -a, in that it sounds more like an option for some kind of robot. In this mode it appears the program will attempt to make sneaky changes without drawing any attention to itself.
|-
| -t||TUMBLE DRY||Perhaps useful for a program that runs on a clothes dryer. Refers to [https://img1.etsystatic.com/000/0/5254504/il_570xN.184726893.jpg directions like these]. Many clothing items are marked "do not tumble dry" in the care instructions, but this would be extremely difficult to make relevant to a program. Given the other flags, this may be less nonsensical than it would first appear. This flag could also be a reference to the dry-run flags that are sometimes available to make command line tools do a simulation run without making any actual modifications to the system.
|-
| -u||UTF-8 MODE; OTHERWISE DEFAULTS TO ANSEL||{{w|ANSEL}} is an old and obscure character encoding that predates ASCII. Using ANSEL as a default would be strange and largely incompatible with most modern systems. By comparison, UTF-8 is standard in the mainstream. Similar in this regard to -q, blerp does something non-standard by default. The problem with using different modes (where the original was also UTF-8) is shown in the title text of [[1683: Digital Data]].
|-
| -U||UPDATE (DEFAULT: FACEBOOK)||Update usually refers to replacing an old software with a newer version. The default here suggests posting a status update to Facebook, sourcing an update from Facebook, or updating Facebook itself.
|-
| -v||VERBOSE; ALIAS TO find / -exec cat {}||Almost standard flag, in ordinary programs the opposite of -q - instead of silencing output, it generates more, usually to help with debugging. For ''blerp'', this flag gets replaced with a command that prints the contents of all files in the filesystem tree. However, it will never complete, as certain device files never end (/dev/urandom contains random bytes). In any case, the "find" command is missing <code>\;</code> and will not run, instead complaining <code>find: missing argument to `-exec'</code> .
|-
| -V||SET VERSION NUMBER||Many programs will have a flag to view their version number. This flag ''changes'' the version number instead. Version number should only be changed when the program is updated (because it's used for distinguishing which edition of a program you have), so manually changing the version number like this is strange and potentially damaging.
|-
| -y||YIKES||{{Wiktionary|yikes}} is an interjection which can express fear or empathy with unpleasant or undesirable circumstances. It is unclear how this would influence the program.
|}

==Transcript==
:[A terminal screen; the background is black and the text is white.]
<div style="background-color:black;color:white;white-space:pre-wrap;font-family:monospace;padding: 0 2em;max-width:50em;">
;NAME
:blerp
;SYNOPSIS
:blerp {[ OPTION | ARGS ]...[ ARGS ... -f [FLAGS] ...}
:blerp {... DIRECTORY ... URL | BLERP} OPTIONS ] -{}
;DESCRIPTION
:blerp FILTERS LOCAL OR REMOTE FILES OR RESOURCES USING PATTERNS DEFINED BY ARGUMENTS AND ENVIRONMENT VARIABLES. THIS BEHAVIOR CAN BE ALTERED BY VARIOUS FLAGS.
;OPTIONS
:-a ATTACK MODE
:-b SUPPRESS BEES
:-— FLAGS USE EM DASHES
:-c COUNT NUMBER OF ARGUMENTS
:-d PIPES OUTPUT TO DEBUG.EXE
:-D DEPRECATED
:-e EXECUTE SOMETHING
:-f FUN MODE
:-g USE GOOGLE
:-h CHECK WHETHER INPUT HALTS
:-i IGNORE CASE (LOWER)
:-I IGNORE CASE (UPPER)
:-jk KIDDING
:-n BEHAVIOR NOT DEFINED
:-o OVERWRITE
:-O OPPOSITE DAY
:-p SET TRUE POPE; ACCEPTS "ROME" OR "AVIGNON"
:-q QUIET MODE; OUTPUT IS PRINTED TO STDOUT INSTEAD OF BEING SPOKEN ALOUD
:-r RANDOMIZE ARGUMENTS
:-R RUN RECURSIVELY ON <nowiki>http://*</nowiki>
:-s FOLLOW SYMBOLIC LINKS SYMBOLICALLY
:-S STEALTH MODE
:-t TUMBLE DRY
:-u UTF-8 MODE; OTHERWISE DEFAULTS TO ANSEL
:-U UPDATE (DEFAULT: FACEBOOK)
:-v VERBOSE; ALIAS TO find / -exec cat {}
:-V SET VERSION NUMBER
:-y YIKES
;SEE ALSO
:blerp(1), blerp(3), blirb(8), blarb(51) blorp(501)(c)(3)
;BUG REPORTS
:<nowiki>http://www.inaturalist.org/taxa/47744-Hemiptera</nowiki>
;COPYRIGHT
:GPL(2)(3+) CC-BY/5.0 RV 41.0 LIKE GECKO/BSD 4(2) OR BEST OFFER
</div>

==Trivia==
Actual UNIX manpages exist on some systems which are written in a similar, nonsensical style to these.
Manual pages distributed for the ''<n>fun'' sections describe similarly humorous "commands" with unusual options.
On some systems, these manual pages are available in funny-manpages or asr-manpages packages.

{{comic discussion}}

[[Category:Programming]]
[[Category:Computers]]
[[Category:BSD]]
[[Category:Bees]]
[[Category:Man pages]]
[[Category:Scientific research]]