Every time you buy tickets on Ticketmaster, you help to digitize a book.

The current business model for language education is the student pays — in particular, the student pays Rosetta Stone $500. The problem with this business model is that 95 percent of the world’s population doesn’t have $500.

The question that motivates my research is, if we can put a man on the Moon with 100,000 [people], what can we do with 100 million?

One fact we're particularly proud of is that there are more people learning languages on Duolingo in the US than there are people learning languages in the entire US public school system.

Because education is such a broad area, I chose to focus on language learning.

[Captchas] are not only annoying, but they kill 10 seconds of your time.

Together with my advisor, Manuel Blum, I co-invented CAPTCHAs, or computer-generated tests that humans are routinely able to pass but that computers have not mastered (they are the squiggly computer letters that are prevalent across the web).