ALL meanings of captcha
CAPTCHA
C c - variable noun captcha Captcha is a system for checking that a human and not a machine is using a computer. Captcha is an abbreviation for 'completely automated public Turing test to tell computers and humans apart'. 3
- noun captcha a test designed to determine whether a computer user is a person or a machine, eg by asking the user to decipher a distorted image 3
- noun Technical meaning of captcha (security) A type of test used to determine whether a request to a website comes from a human or a computer program, typically by asking the user to perform some kind of image recognition task such as reading distorted text. The term was coined in 2000 by Luis von Ahn, Manuel Blum, Nicholas J. Hopper (all of Carnegie Mellon University) and John Langford (of IBM) as a contrived acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart". CAPTCHA aims to prevent software tools from performing actions which might degrade the service, such as registering user accounts or automating the playing of a game. 1
- noun captcha an online test designed so that humans but not computers are able to pass it, used as a security measure and usually involving a visual-perception task: Site visitors must solve the “distorted text” CAPTCHA before posting comments. 1
- noun captcha a computer program that generates such tests. 1
- noun captcha A program or system intended to distinguish human from machine input, typically as a way of thwarting spam and automated extraction of data from websites. 1
- noun captcha Alternative letter-case form of CAPTCHA. 0