A type of test used mostly for interaction with a website designed to tell humans apart from computers. Since the ability for software has grown it often can present problems in situations where any input is made available online, developers can create robots to fill out forms automatically and with impressive speeds. This circumvention of actual human input often creates massive problems for the service provider, forcing the use of a Captcha to test the authenticity of the input. Usually a Captcha can be recognized as an image containing somewhat distorted string of words or letters.
The term CAPTCHA is a contrived acronym which stands for “Completely Automated Public Turing test to tell Computers and Humans Apart.”
