Berlin is one of my favorite cities in the world. I feel like the energy is very youthful. It has such an important history, including its recent history of unification.

It took 10 years to go from building the initial Smartphone to reaching the mass market. BlackBerry came out in 2003 and it didn't get to about a billion units until 2013. So I can't imagine it would be much faster for VR.

There is a huge need and a huge opportunity to get everyone in the world connected, to give everyone a voice and to help transform society for the future. The scale of the technology and infrastructure that must be built is unprecedented, and we believe this is the most important problem we can focus on.

There are many machines throughout history that were built to do something better than a human can.

I got my first computer in the 6th grade or so. As soon as I got it, I was interested in finding out how it worked and how the programs worked and then figuring out how to write programs at just deeper and deeper levels within the system.

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.

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