This is a perverse thing, personally, but I would rather be in the cycle where people are underestimating us. It gives us latitude to go out and make big bets that excite and amaze people.

People influence people. Nothing influences people more than a recommendation from a trusted friend. A trusted referral influences people more than the best broadcast message. A trusted referral is the Holy Grail of advertising.

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.

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

Our goal is not to build a platform; it's to be cross all of them.

If we want to have the biggest impact, the best way to do this is to make sure we always focus on solving the most important problems.

The thing that we are trying to do at Facebook is just help people connect and communicate more efficiently.