Free Securing Web Forms with PEAR’s Text_CAPTCHA Tutorial

Note: According to Wikipedia, a Turing test is a proposalfor a test of a machine’s capability to perform human-like conversation.You have probably seen the CAPTCHA project in action at some of your Webdestinations. Its principal tool is a randomly created image that contains aphrase unmentioned in computer-readable text on the rendered page. The formasks the user to provide the phrase. If the form post does not contain thecorrect phrase, you can safely assume either the human made  
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