Wednesday, October 01, 2008

Using word verification to help digitize books

Everyone has had to type a word or sequence of symbols to verify that they are a human before signing up for an online account like Facebook, Flickr, Gmail etc. I will have to type these words/symbols before posting this to various blogs. These verifications are also known as CAPTCHA (Completely Automated Turing Test To Tell Computers and Humans Apart).

A Carnegie Mellon University scientist, Luis von Ahn, calculated that people waste close to 500,000 hours every day typing these characters. Luis von Ahn consequently developed reCAPTCHA which connects all of this immense brain power to help digitize old books and he and his colleagues reported in Science that “over the last year Web users have transcribed enough text to fill up more than 17,600 books, with better than 99 percent accuracy.”

To read/listen to the story visit

To learn more about reCAPTCHA visit

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