I finished reading High Output Management by Andrew Grove, which had such valuable insights for leaders that I've been forcing managers at Duolingo to read the book.

I finished reading High Output Management by Andrew Grove, which had such valuable insights for leaders that I've been forcing managers at Duolingo to read the book.

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?

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.

Before the Internet, coordinating more than 100,000 people, let alone paying them, was essentially impossible. But now with the Internet, I've just shown you a project where we've gotten 750 million people to help us digitize human knowledge.

This sounds strange to many people, but I work out for exactly 16 minutes every day, and do so at maximum speed by running 2.5 miles. This keeps me healthy without taking up too much time so I can stay focused on other things. It's one of the most efficient things I do each day.

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).