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The creators of a website called Duolingo want to translate the world’s Web pages into new languages by harnessing the efforts of people who are learning those languages.

If the approach sounds familiar, it’s because a similar idea is the basis of the effort known as reCAPTCHA, which was invented by the same Carnegie Mellon computer science professor behind the new project: Luis von Ahn.

A recaptcha is a string of distorted text shown to a user trying to register for a new account or comment on a Web page; the text comes from electronically scanned print that could not be recognized by a computer. To gain permission, the user must reënter the words correctly. More than a hundred million recaptchas are solved each day. Von Ahn says that if he can capture even a small portion of that audience with Duolingo—say, a million users—he could translate all of Wikipedia’s English entries into Spanish in 80 hours.

Even though the Duolingo site has yet to launch—von Ahn says it will enter private beta “on the order of weeks” from now—he was able to reveal a few details about how it operates. The basic premise is simple: users, even those who have never spoken a particular language before, are presented with short phrases on which to practice. The system helps them by defining some of the words in the phrase.

Users’ attempts to translate the phrase are later voted on by other users, and the most accurate translation “wins.” In a talk given at a recent TEDx conference at Carnegie Mellon, he said that the results “are as accurate as translations from professional language translators.”

As for Duolingo’s capabilities as a language teacher, Von Ahn says his team’s tests indicate that users “do about as well as with other methods.”

Duolingo has one big advantage over other language tools: it’s free. This means its potential audience is enormous, encompassing anyone with a computer. Eventually, says von Ahn, he wants to make the system accessible by mobile phones, which would increase its reach by hundreds of millions, if not billions, of potential users.

“These guys are brilliant,” says Christopher O’Donnell, former head of product at Transparent, a maker of language-learning software whose customers include the U.S. Department of Defense. “They might be on to something super elegant and amazingly perfect, like recaptcha was. If they do the recaptcha of language, it’s massive.”

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Credit: Luis von Ahn

Tagged: Computing, languages, Duolingo, translations, CMU

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