It is really important for us that people understand what the strategy is and that the real approach is to make everything social, not to build a vertical approach.

I mean, we've built a lot of products that we think are good, and will help people share photos and share videos and write messages to each other. But it's really all about how people are spreading Facebook around the world in all these different countries. And that's what's so amazing about the scale that it's at today.

The biggest risk is not taking any risk.

We want Facebook to be one of the best places people can go to learn how to build stuff.

We're really at this point where we can take a step back and think about the next big things that we want to do.

When I'm introspective about the last few years I think the biggest mistake that we made, as a company, is betting too much on HTML5 as opposed to native... because it just wasn't there. And it's not that HTML5 is bad. I'm actually, on long-term, really excited about it. One of the things that's interesting is we actually have more people on a daily basis using mobile Web Facebook than we have using our iOS or Android apps combined. So mobile Web is a big thing for us.

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