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.

The question I ask myself like almost every day is: ‘Am I doing the most important thing I could be doing?' Unless I feel like I’m working on the most important problem that I can help with, then I’m not going to feel good about how I’m spending my time. And that’s what this company is.

Connecting the world is really important, and that is something that we want to do. That is why Facebook is here on this planet.

We are working hard to build a service that everyone, everywhere can use, whether they are a person, a company, a president or an organisation working for change

It only took me two weeks to build the first version of Facebook because I had so much stuff before then.

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.

Of course the Silicon Valley is unique and Berlin is not yet comparable. But of all the different cities that are building a startup infrastructure, Berlin is the one with the most similar energy.