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.

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

I am an early riser, and always wake up between 5 and 6am.

If you get asked to do something that would take place down the road (say you get asked to speak at a conference that's a year away) and you wouldn't want to do it if it were taking place next week, then don't do it. This advice has helped me evaluate the opportunities that I truly want to dedicate my time to and those that I don't.

People are good at figuring out what's attractive, and computers are good at quickly searching and finding. You put them together, and bang!

I co-founded Duolingo with the mission of bringing free language education to the world.

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?