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.

We want Facebook to be one of the best places people can go to learn how to build stuff. If you want to build a company, nothing better than jumping in and trying to build one. But Facebook is also great for entrepreneurs/hackers. If people want to come for a few years and move on and build something great, that's something we're proud of.

I literally coded Facebook in my dorm room and launched it from my dorm room. I rented a server for $85 a month, and I funded it by putting an ad on the side, and we've funded ever since by putting ads on the side.

Don't discount yourself, no matter what you're doing.

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.

For the first time we're allowing developers who don't work at Facebook to develop applications just as if they were. That's a big deal because it means that all developers have a new way of doing business if they choose to take advantage of it. There are whole companies that are forming whose only product is a Facebook Platform application.

There are a few other things that I built when I was at Harvard that were kind of smaller versions of Facebook. One such program was this program called Match. People could enter the different courses that they were taking, and see what other courses would be correlated with the courses they are taking.