I literally coded Facebook in my dorm room and launched it from my dorm room. I rented a server for $85 a month, and I funded it by putting an ad on the side, and we've funded ever since by putting ads on the side.

No one has done a study on this, as far as I can tell, but I think Facebook might be the first place where a large number of people have come out. We didn't create that - society was generally ready for that. I think this is just part of the general trend that we talked about, about society being more open, and I think that's good.

My friends are people who like building cool stuff. We always have this joke about people who want to just start companies without making something valuable. There's a lot of that in Silicon Valley.

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

Facebook is inherently viral. There are lots of sites that include a contact importer, and for lots of them it doesn't really make sense. For Facebook it fits so well. It wasn't until a few years in that we started building some tools that made it easier to import friends to the site. That was a huge thing that spiked growth.

There are people who are really good managers, people who can manage a big organization, and then there are people who are very analytic or focused on strategy. Those two types don't usually tend to be in the same person. I would put myself much more in the latter camp.

I like to pride myself on thinking pretty long term, but not that long term.