The companies that work are the ones that people really care about and have a vision for the world so do something you like.

When I was in college I did a lot of stupid things and I don't want to make an excuse for that. Some of the things that people accuse me of are true, some of them aren't. There are pranks, IMs.

Find that thing you are super passionate about. A lot of founding principles of Facebook are that if people have access to more information and are more connected, it will make the world better; people will have more understanding, more empathy. That’s the guiding principle for me. On hard days, I really just step back, and that’s the thing that keeps me going.

Our strategy is very horizontal. We're trying to build a social layer for everything. Basically we're trying to make it so that every app everywhere can be social whether it's on the web, or mobile, or other devices.

On engagement, we're already seeing that mobile users are more likely to be daily active users than desktop users. They're more likely to use Facebook six or seven days of the week.

We also have a dog. His name's Beast. He's a sheepdog. He's super cute. I love him.

My number one piece of advice is: you should learn how to program.