Unlike similar implementations, this PHP CAPTCHA class works without cookies. It is extremely easy to integrate into existing sites and your <form> processing logic. And it requires no database.

It strives to be more user-friendly. It gives visual feedback while you enter a solution (AJAX). And it accepts a few misguessed letters. Additionally it has an accessible riddle built in, optional modules and many configuration settings.

Following is a pseudo blog comment field - only here for testing:

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