We have a new feature here at our little blog site, captcha with a purpose :-). Hopefully this will combat spam problems and promote literacy at the same time! And for those who have a hard time reading the text, there is an audio option. Happy commenting!
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.