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)