PHP Captcha Security

This script generates images (known as “Captcha’s”) which contain security codes used for protecting a form from spam bots. By encoding a ‘password’ inside an image and asking the user to re-enter what they see you can verify the user is a human and not automated software submitting your form. Why not try out the following form with valid and invalid codes to see how it works.

Xem ví dụ


Mã xác nhận:
Xem bài viết ở đây http://www.white-hat-web-design.co.uk/articles/php-captcha.php 

Download code http://www.white-hat-web-design.co.uk/articles/captcha.zip