The Internet may be a global tool, but it’s still segmented into pieces. If you don’t speak Chinese, French, Spanish, or any number of other languages, you’re only getting a glimpse of the entire thing. Luis Von Ahn, one of the creators of CAPTCHA –the incredibly annoying system that asks you to type words and numbers into a little box to ensure that you’re human–is wielding his considerable Internet mojo to eliminate the web’s language barrier. Anyone who wants to learn a new language can help.

Von Ahn’s brainchild is Duolingo, a project that teaches users a language of their choosing (Spanish, German, and in the future, Chinese, Italian, and French) and allows them to translate websites and documents in the process. “You can try to use computers to translate, but that doesn’t really work, and it won’t for the next 20 to 30 years. With humans, you need to find a way to motivate them to translate at a very large scale,” explains Von Ahn. “You can’t ask people to translate the whole web because it would be way too expensive. Teaching a language is a way to motivate, and a lot of learning happens through translation.”

Duolingo’s translation ability is surprisingly accurate. The site asks users to go through language lessons so it can determine skill level. That way, only skilled users are asked to translate complicated sentences. Beginners only have to deal with simple translations–sentences like “I am a girl.” Lessons requiring more skill (and their accompanying translations) are locked until users successfully complete the simpler tasks.

Users also have the opportunity to vote on the quality of other people’s translations, and Duolingo compiles input from multiple users to make its final translations. The system is accurate, as you can see in the picture above. The second sentence was translated by a professional translator, and the third was done by Duolingo.

So far, Duolingo has translated over 10,000 sentences, all from documents with Creative Commons licenses. By early 2012, Von Ahn hopes Duolingo can start accepting items from users to be translated. Duolingo may also one day allow native speakers of languages other than English to contribute–translating a Spanish document into Chinese, for example.

Duolingo is slowly accepting users from its waiting list, which contains over 100,000 eager translators. If you want to sign up, check out the site here. And just think about the potential impact: with one million users signed up, Duolingo could translate Wikipedia from English to Spanish in 80 hours.