captcha

can anyone recommend a good captcha script that's free and doesn't require credits?

(when i say captcha I mean the image that a person has to type the characters to prevent spammers from filling out the form)

If you don't have the ability to install a component then you won't be able to use a proper captcha script.

You can make a fake work around.

Create images that contain numbers and letters.
Read these into an array
Create a random number script to output 5 of them as images.

all the captcha scripts i know are in php