Definition:
A CAPTCHA™ is a part of a web form that attempts to ensure that the person filling out the form is indeed a person, and not a computer. The goal of a CAPTCHA is to reduce the amount of spam received by forms from
The term CAPTCHA is trademarked by Carnegie Mellon University and stands for Completely Automated Public Turing test to Tell Computers and Humans Apart.
Pronunciation: ˈkæptʃə
Also Known As:
CAPTCHAs are often refered to as reverse Turing tests because they are administered by a computer, attempting to prove that the test taker is a human.
A Turing test was invented by Alan Turing as a dialog between a human and a computer, where the human could not tell that they were talking to a computer. So a reverse Turing test would be determing when a computer is not human.
