Facebook was not originally created to be a company. It was built to accomplish a social mission - to make the world more open and connected.

Right now, with social networks and other tools on the Internet, all of these 500 million people have a way to say what they're thinking and have their voice be heard.

Move fast and break things. Unless you are breaking stuff, you are not moving fast enough.

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.

The world is changing so quickly, with mobile stuff and different platforms emerging, that I think it's more likely that the biggest competitor for Facebook is someone that we haven't heard of. What that means for us is that we should just really stay focused on what we're doing.

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.

The world isn't set up equally, and the first billion people using Facebook have way more money than the rest of the world combined.