Thursday, April 17, 2008


Completely Automated Public Turing test to tell Computers and Humans Apart.

Well, that's the full form of CAPTCHA, something we're familiar with and encounter everyday. The definition, as cited by Nemesys goes like this: A test that is designed to be easy for a human to do, but be difficult to automate. An example of a captcha is the practice of displaying distorted letters and asking the user to type them into a form.

As I was about to download something from one of the so-called free hosts just a few minutes ago, I saw the weirdest CAPTCHA I've faced so far. Unaware of the underlying trap I simply typed all the characters displayed but immediately got an error message. Only then I read the funny instruction right above it and couldn't help laughing alone in my room, in the middle of the night.
Watch out for such dual purpose CAPTCHAs, smart enough to annoy humans apart from deceiving OCR software.

1 comment:

  1. I never encountered such a thing before - it's really innovative, and a cool idea to implement!