Ever get stuck on one of those login screens where you have to pick out some hard-to-read text in a squiggly, multi-colored image? Those images are called CAPTCHAs, which is an acronym for Completely Automated Public Turing test to tell Computers and Humans Apart. What a deliciously geeky acronym. Wikipedia has a pretty good article on the history and current state of the captcha, with links to current captcha implementations.
It's interesting to note that by definition, the Captcha doesn't have to be an image with text. It just has to be some kind of task that's easy for a human to solve, but difficult for a machine. It could be a sound clip or an easily identified image, like a picture of an animal.
I find the social engineering used to trick people into deciphering captchas to be pretty amusing. It just goes to show that you just can't devise an algorithm to defeat human nature.
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You are great! But I still did good! Hey!
Posted by: Microsoft Office | December 16, 2011 at 03:52 AM