Facebook is uniquely positioned to answer questions that people have, like, what sushi restaurants have my friends gone to in New York lately and liked? These are queries you could potentially do with Facebook that you couldn't do with anything else, we just have to do it.

If you recognize that self-driving cars are going to prevent car accidents, AI will be responsible for reducing one of the leading causes of death in the world.

We have a pretty ambitious goal for the world. What we think will make the Web better. What we think will make all these businesses that integrate with us run more effectively. I think if we stay focused on doing that, that's really the main thing that we need to do.

The question I ask myself like almost every day is: ‘Am I doing the most important thing I could be doing?' Unless I feel like I’m working on the most important problem that I can help with, then I’m not going to feel good about how I’m spending my time. And that’s what this company is.

I think that people just have this core desire to express who they are. And I think that's always existed.

Facebook is inherently viral. There are lots of sites that include a contact importer, and for lots of them it doesn't really make sense. For Facebook it fits so well. It wasn't until a few years in that we started building some tools that made it easier to import friends to the site. That was a huge thing that spiked growth.

Nothing influences people more than are commendation from a trusted friend.