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Author: Jorge Peña

What is reCAPTCHA?

reCAPTCHA is an anti-spam method originating from Carnegie Mellon University which uses CAPTCHAs in a genius way. Instead of randomly generating useless characters which users grow tired of continuosly typing in, risking the possibility that spammers will eventually write sophisticated spam bots which use OCR libraries to read the characters, reCAPTCHA uses a different approach.

While the world is in the process of digitizing books, sometimes certain words cannot be read. reCAPTCHA uses a combination of these words, further distorts them, and then constructs a CAPTCHA image. After a ceratin percentage of users solve the 'uknown' word the same way it is assumed that it is the correct spelling of the word. This helps digitize books, giving users a reason to solve reCAPTCHA forms. Because the industry level scanners and OCR software which are used to digitize the books can't read the words with which the CAPTCHAs are constructed, it is safe to assume that in-house spam-bot OCR techniques will not be able to bypass the CAPTCHA either.

reCAPTCHA has earned a very prestigious reputation among the various CAPTCHA systems available and is used by such sites as Facebook, Twitter, StumbleUpon, and a few U.S. Government Websites such as the TV Converter Box Coupon Program Website.

This plugin is WordPress MU compatible.

For more information please view the plugin page..