In a lot of ways Berlin is a symbol for me of Facebook's mission: bringing people together, connecting people and breaking down boundaries.

This is our commitment to users and the people who use our service, is that Facebook's a free service. It's free now. It will always be free. We make money through having advertisements and things like that.

It's not because of the amount of money. For me and my colleagues, the most important thing is that we create an open information flow for people. Having media corporations owned by conglomerates is just not an attractive idea to me.

When I started Facebook from my dorm room in 2004, the idea that my roommates and I talked about all the time was a world that was more open.

Our mission is to make the world more open and connected. We do this by giving people the power to share whatever they want and be connected to whoever they want, no matter where they are.

Don't discount yourself, no matter what you're doing.

In addition to building better products, a more open world will also encourage businesses to engage with their customers directly and authentically. More than four million businesses have Pages on Facebook that they use to have a dialogue with their customers. We expect this trend to grow as well.