Carnegie Mellon University computer scientists have spun off a new, free website called Duolingo, where language learners translate real-world texts from the Internet while they're building vocabulary and grammar skills.
A beta test with 100,000 people showed that the quality of the translation equals that of a professional translator. Learners are given sentences at their ability level. They can click on words they don't understand and get a definition. They can see others' translations. Groups of ten learners eventually vote for the translation they think is the best.
Since Internet users can only understand content in the language or languages they know, CMU Professor Luis von Ahn said, "We would like to translate the entire Web into every major language." Right now, Duolingo offers lessons in English, Spanish, French and German, with Portuguese and Chinese to be added soon.
Professor von Ahn won a 2006 MacArthur Genius Grant for his work in harnessing the brain power of human beings to accomplish useful tasks that digital computers cannot perform. He developed the CAPTCHA tests, in which Internet users must type distorted characters to prove they're human beings, not computers out to exploit a site.
When he learned a CAPTCHA was being typed 200 million times a day, von Ahn was initially proud of the far-reaching effect he had had, but then he regretted the 500,000 hours people were wasting everyday and wondered if something useful could be accomplished in the process. The result was a spinoff company, reCAPTCHA Inc., acquired by Google in 2009. The distorted characters used now are from old books that computers cannot scan, so people are helping to digitize previously inaccessible material.
Humanity's great achievements — the Pyramids, the Panama Canal, landing on the moon — have all involved about 100,000 people, according to von Ahn. "That's because before the Internet, coordinating more than 100,000 people was impossible … But now with the Internet, we can coordinate millions of people, and the question is, if we can put a man on the moon with a hundred thousand, what can we do with a hundred million?"