It used to be the case, like, you'd switch jobs, and then maybe you wouldn't keep in touch with all the people that you knew from that old job. Just because it was too hard. But one of the things that Facebook does is it makes it really easy to just stay in touch with all these people.

You know, you really don't need a forensics team to get to the bottom of this. If you guys were the inventors of Facebook, you'd have invented Facebook.

If a product costs $10,000 or $20,000 it has limited use. This is what the first computers cost! Only when almost everyone is able to afford it will it be a real thing.

You hear these stories about people who take apart their radio and put it back. Or just learn a lot from taking it apart. But I wasn't as into that stuff as I was just into how computer programs work.

Companies face a handful of different risks, whether it is competitors or different market environments. But I think that people focus way too much on competitors and not enough on their own execution.

Facebook is all about information and helping people share it.

The web is at a really important turning point right now. Up until recently, the default on the web has been that most things aren’t social and most things don’t use your real identity. We’re building toward a web where the default is social.