I usually make to-do lists with timelines, and pen and paper does the trick for me.

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.

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

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

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.

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