CAPTCHA

CAPTCHA (Completely Automated Public Turing Test) is a system that is specifically designed to differentiate between humans and internet robots. It does this by setting a specific criteria that is easily performed by humans, yet difficult and time consuming for bots to complete. A CAPTCHA is most commonly used to prevent bots and other automated software from using blogs and social networking sites as a spamming platform. It frequently uses an image file of slightly scrambled or distorted alphanumeric characters to prove validation. These characters are usually easily read by human eyes. While a bot is able to detect the presence of an image, it has no idea of what the image actually is, preventing it from entering the correct data and gaining access. Once a user has successfully completed a specific CAPTCHA challenge, they are granted access. Their information may then be logged to elude the CAPTCHA for future requests.