Possible Duplicate:
PHP Captcha without session
That after I send a form I get to captcha page - than I go back to the form? How to do it? Should I use session?
I know how to implement captcha on form page but I wonder how it's done: that I get redirected to verification page ex. https://stackoverflow.com/captcha?s=f689274e-e760-482d-a008-31d4bd469f80
I don't need any specific explanation - I would like to get an idea.
Recaptcha has easy-to-install plugins, all you have to do is get it and follow the instructions.