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).

In 2011, after spending a couple of years working at Google, I decided that I wanted to dedicate myself to helping to transform education. I was particularly inspired by my upbringing in Guatemala, a poor country where high-quality educational opportunities are limited to those who have money.

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.

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?

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

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

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