A lot of the time the experts, the people who are supposed to be able to tell you what to do, will tell you that you can't do something even when you know you can. And a lot of the time it's your friends ... who tell you you can do it.

We used to write this down by saying, 'move fast and break things.' And the idea was, unless you are breaking some stuff you are not moving fast enough. I think there's probably something in that for other entrepreneurs to learn which is that making mistakes is okay. At the end of the day, the goal of building something is to build something, not to not make mistakes.

Some of the best ideas throughout the company's evolution have been from places all throughout the company whether it's an engineer or someone on the customer support team. Just different areas around the company.

I think as a company, if you can get two things right--having a clear direction on what you are trying to do and bringing in great people who can execute on the stuff--then you can do pretty well.

Our mission is to make the world more open and connected. We do this by giving people the power to share whatever they want and be connected to whoever they want, no matter where they are.

Google, I think, in some ways, is more competitive and certainly is trying to build their own little version of Facebook.

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.