Make Captcha using php in 5 minutes

Here is a small PHP tutorial for you ….Hope you have noticed Image verification used in many sites to avoid spam.This is called CAPTCHA.I will tell you how you can make an Image verification for your website in PHP.I will guarantee you,its very simple and can make you in 5 min.What we a re doing is, we are generating a random number and writing it into an image and displaying it