A CAPTCHA is a type of challenge-response test used to determine whether a user is human. Because a computer program is unable to solve the CAPTCHA, any user entering a correct solution is presumed to be human.
That being said, how many times have you gone to a site only to be presented with a CAPTCHA image so distorted that it took you 3 tries just to get by it? How many times have you said the hell with it and just left the site? The problem is that the OCR systems used by the automated systems are getting better and better and the images we humans are expected to recognize are getting more and more difficult to make out.
Well, instead of relying on distorted images that are hard for even a human to read I decided to create a CAPTCHA system that is extremely easy for a human to deal with yet very difficult for an automated computer program to sort out. My system uses no distorted image, but instead tests you in a more human way. In addition to that (http referrer checks), (iframes), (randomization), and (color shuffling) are utilized to Prevent BOTS from being able to solve the test.
The best part is that this system is Pure ASP code and no special components are needed on the server. You can add the CAPTCHA to your existing forms and start enjoying less spam submissions right away.