WebAIM - Web Accessibility In Mind

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Re: Alternatives for the CAPTCHA


From: Chris Hoffman
Date: Mar 23, 2009 7:50PM

Why not flip the problem on its head, and ask, "What are people really
bad at that computers are good at?"

Then provide a problem that a computer algorithm would get _right_,
but that a human being would get _wrong_. Exploit the cognitive biases
that we have but computers don't.

Yet another approach would be to use natural language parsing
problems, which are very difficult for computers. For example, ask
"Which of the following is a valid English sentence: 'The dress Mom
bought Dad's sister fits' or 'The dress Mom bought myself fits' ?"