If Facebook were a country, it would be the 8th most populated in the world, just ahead of Japan.

There are a few other things that I built when I was at Harvard that were kind of smaller versions of Facebook.

In a lot of ways Berlin is a symbol for me of Facebook's mission: bringing people together, connecting people and breaking down boundaries.

It only took me two weeks to build the first version of Facebook because I had so much stuff before then.

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.

It is important for young entrepreneurs to be adequately self-aware to know what they do not know.

I look at Google and think they have a strong academic culture. Elegant solutions to complex problems.