Have you ever tried logging in or registering to a website and you were asked to identify some distorted numbers and letters and type it into the provided box? That is the CAPTCHA system.

The CAPTCHA helps to verify whether your site's visitor is an actual human being or a robot. Not a robot like you see in the Terminator movie but an automated software to generate undesired electronic messages (or content). In short, CAPTCHA protects you from SPAM.