Building a mission and building a business go hand in hand.

A guy who makes a new chair doesn't owe money to everyone who ever built a chair.

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.

The basis of our partnership strategy and our partnership approach: We build the social technology. They provide the music.

We have a pretty ambitious goal for the world. What we think will make the Web better. What we think will make all these businesses that integrate with us run more effectively. I think if we stay focused on doing that, that's really the main thing that we need to do.

If the original Facebook was the first five minutes [of a conversation] and the stream was the next 15, what I want to show you today is the rest-the next few hours of a deep engaging conversation.

I think as a company, if you can get two things right--having a clear direction on what you are trying to do and bringing in great people who can execute on the stuff--then you can do pretty well.