How do I add a CAPTCHA to my PHP form?

Question

My knowledge of php is not good and I need help.

I have this php form but I don't know how to add a CAPTCHA mechanism.

How do I achieve this?

Answer 1

Check out recaptcha

Answer 2

Recaptcha is probably best. But if you just want ot do it in PHP look at the GD libs in PHP to generate the images. I did one for a company with that

http://greenlee.com/Service/Forms/eb_req.shtml

Answer 3

I really like Securimage is seems to work really well and does not require a third-party external service or javascript (unless you enable the new image feature). Also it can be configured to provide audio captcha for accessibility.