from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A distorted image of letters and numbers used to prevent automated use of websites.
  • n. Anything that a human must do to prove that they are not a computer.


Coined by a team of researchers at Carnegie Mellon University in 2000 as a loose Acronym of "Completely Automated Public Turing test to tell Computers and Humans Apart". (Wiktionary)


  • The term CAPTCHA is an acronym that means "Completely Automated Public Turing test to tell Computers and Humans Apart". The Ad-Free Personal Finance Blogs Aggregator

  • Solving the CAPTCHA is the final step in creating a new Facebook account.

    Facebook users unwittingly spread Koobface worm

  • Luis von Ahn, the reCAPTCHA founder who co-authored Google's blog post, is one of the Carnegie Mellon researchers who coined the term CAPTCHA, short for Completely Automated Public Turing test to tell Computers and Humans Apart.

    The Register

  • If you have ever re-typed two squiggly words on websites like Craigslist, Facebook, or Ticketmaster during an online registration or purchase process, then you already know one of von Ahn's previous start-ups. reCAPTCHA reduces spam on email and social media sites as well as e-commerce fraud by preventing automated bots from signing up for thousands of new accounts, hence the acronym CAPTCHA, which stands for "Completely Automated Public Turing test to tell Computers and Humans Apart."

    Joe Kutchera: Translate the Web While Learning a New Language

  • The whole premise behind the CAPTCHA is you want to allow users to access your service, as long as they're an actual person.

    Spammers Use The Human Touch To Avoid CAPTCHA

  • For people who use screen-reading software, CAPTCHA is actually an image and can't be read by that software.

    Petition for better accessibility of Yahoo!

  • You must ALWAYS fill in the two word CAPTCHA below to submit a comment.


  • A CAPTCHA is a simple test to determine if a user is human or computer.


  • The primary hindrance to mass purchasing is an authorization mechanism known as CAPTCHA - images of random words, usually presented in an unusual font or with lines running through the letters, that the user must re-type before proceeding.

    The Globe and Mail - Home RSS feed

  • She further dismissed the relevance of the Lori Drew case, saying the Wiseguy case is more substantive and involves not only allegations of breaches of contract but also of code-based restrictions, that is, the CAPTCHA features.

    Wired Top Stories


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