More than four million businesses have Pages on Facebook that they use to have a dialogue with their customers.

At Facebook, we're inspired by technologies that have revolutionized how people spread and consume information. We often talk about inventions like the printing press and the television - by simply making communication more efficient, they led to a complete transformation of many important parts of society. They gave more people a voice. They encouraged progress. They changed the way society was organized. They brought us closer together.

I don't have an alarm clock. If someone needs to wake me up, then I have my BlackBerry next to me.

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.

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

Berlin definitely has one of the most vibrant of the startup scenes that I have seen. Not really just across Europe, but across the whole world in terms of cities. It's an interesting dynamic.

The trick isn't adding stuff, it's taking away.