Hi friends, i think you are very familiar with the word captcha. When we are publishing a comment on others blog, the bot asks us to enter a set of characters to accept that comment. Thus a captcha ensures that the comment is not published by a spam or bot.... More clearly speaking
A CAPTCHA is a program that can generate and grade tests that humans can pass but current computer programs cannot. For example, humans can read distorted text as the one shown below, but current computer programs can't.
The term CAPTCHA (for Completely Automated Turing Test To Tell Computers and Humans Apart) was coined in 2000 by Luis von Ahn, Manuel Blum, Nicholas Hopper and John Langford of Carnegie Mellon University.
Thus if your website needs protection from abuse, it is recommended that you use a CAPTCHA. There are many CAPTCHA implementations, some better than others.
So use any one of them to save your site from spams.......
