2496: Mine Captcha

2021-07-30T16:02:22Z

Lonefeather: Added introductory paragraph to provide more context regarding the reCAPTCHA system of which the comic is making a joke.

{{comic
| number = 2496
| date = July 30, 2021
| title = Mine Captcha
| image = mine_captcha.png
| titletext = This data is actually going into improving our self-driving car project, so hurry up--it's almost at the minefield.
}}

==Explanation==
{{incomplete|Created by a LIVE MINEFIELD. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

This comic, like [[1897: Self Driving]], references the approach of using {{W|CAPTCHA}} inputs to solve problems, particularly those involving image classification, which are not solvable by computers, specifically {{W|reCAPTCHA}} v2's fallback puzzle which is based on identifying road features and vehicles. A reCAPTCHA version of this puzzle might ask a user to "check all squares containing a STOP SIGN." The CAPTCHA in this comic, however, asks the user to "Click all the pictures of MINES" by, ironically, clicking on squares that do not show anything more than a gray square, with the understanding that some of those gray squares are hiding 'mines' in a [[wikipedia:Minesweeper (video game)|Minesweeper puzzle game]]. Furthermore, the CAPTCHA in this comic asks the user to click on the squares containing mines themselves, which is the opposite of the traditional goal in Minesweeper, which is to click on all boxes where there are *no* mines, and solving the puzzle is usually (although not in this case) impossible without revealing the information in those squares without mines. So the CAPTCHA in this comic would be especially difficult for a user who is familiar with how to play Minesweeper, in addition to being difficult for a user who is familiar with the normal CAPTCHA image-selection puzzle.

A captcha (also spelled CAPTCHA) is a challenge designed to be solvable by humans, but not by computer programs. It is used to protect websites from automated software. For example, editing the explain xkcd wiki without being logged in requires the user to solve a Captcha.

The captcha depicted in this comic is similar in layout to one of the challenges of ''reCAPTCHA'', a captcha system developed by Google. It requires the user to click on several of 16 tiles laid out in a 4x4 grid.

This comic expects users click on the mines in a minesweeper puzzle to proceed with their task. Traditionally, the goal in minesweeper is to click on boxes where there are NOT mines, so the puzzle would be especially difficult for anyone used to playing minesweeper.

The comic shows a 4x4 grid with mostly grey squares, and a few tiles showing colored numbers. The setup and colors suggest a gaming board of the popular minesweeper game, with a few tiles uncovered. Numbers would then show the number of mines in adjacent squares. Given the current board configuration, one can deduce that there are four mines (in squares A2, B2, B3 and D3, where letters (numbers) mark columns (rows)). For example, there are two mines within the squares A2,B1,B2, as signified by the 2 in A1, but only one of those can be in B1 or B2 (because of the 1 in C1). Therefore, A2 has to be a mine. The title suggests this as a CAPTCHA, where proving to be human involves first recognizing this as a minesweeper simile, and then solving for those squares with mines.

Traditionally, the goal in minesweeper is to click on boxes where there are NOT mines, and solving the puzzle is usually (although not in this case) impossible without revealing the information in those squares, so the puzzle could easily trip up anyone used to playing minesweeper.

The title text is similar to [[1897: Self Driving]] where the CAPTCHA solver is asked to "answer quickly – [the] self-driving car is almost at the intersection".

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[A "CAPTCHA" box.]

To proceed, click<br>all the pictures of<br>MINES

[A 4 by 4 ''Minesweeper'' field, with some cells revealed with numbers. Each number is drawn in a different font/style.]

<pre>
2 . 1 .
. . 3 .
3 . . .
. 1 . 1
</pre>

{{comic discussion}}

[[Category:CAPTCHA]]

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2496: Mine Captcha