What is CAPTCHA?
A response test used to ensure that the response is not produced by a computer. The process involves asking a user to complete a simple test which is then graded. A correct solution is presumed to be human because computers are supposedly unable to solve a CAPTCHA test.
CAPTCHA stands for Completely Automated Public Turing test to tell Computers and Humans Apart and was created by four colleagues at Carnegie Mellon University.
This is an example of a form that collects basic user information and utilizes a CAPTCHA to ensure that all submitters are “human”. Good CAPTCHA implementation requires a balance of outsmarting captcha bypassers and making the user experience as simple as possible.