CAPTCHA
A CAPTCHA is a program that protects websites against bots by generating and grading tests that humans can pass but current computer programs cannot. For example, humans can read distorted text as the one shown below, but current computer programs can’t.
A free, secure and accessible CAPTCHA implementation is available from the reCAPTCHA project. Easy to install plugins are available for WordPress, MediaWiki, PHP, Perl, Python, and many other environments. reCAPTCHA also comes with an audio test to ensure that blind users can freely navigate your site. reCAPTCHA is our officially recommended CAPTCHA implementation.
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