CAPTCHA codes are used by computers to tell bots and humans apart (CAPTCHA stands for "Completely Automated Public Turing test to tell Computers and Humans Apart").
A CAPTCHA frequently appears as a line of warped text and numbers that a human must read and type in in order to proceed.
Drawing inspiration from the tech tool, architect Aram Bartholl has created "CAPTCHA graffiti" that he posts throughout the urban landscape.
Check it out in the video below, then see the funniest, most inappropriate CAPTCHAs ever.
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