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.

When I'm introspective about the last few years I think the biggest mistake that we made, as a company, is betting too much on HTML5 as opposed to native... because it just wasn't there. And it's not that HTML5 is bad. I'm actually, on long-term, really excited about it. One of the things that's interesting is we actually have more people on a daily basis using mobile Web Facebook than we have using our iOS or Android apps combined. So mobile Web is a big thing for us.

Facebook is inherently viral.

Today we can only hear the voices and witness the imaginations of one-third of the world's people. We are all being robbed of the creativity and potential of the two-thirds of the world not yet online. Tomorrow, if we succeed, the Internet will truly represent everyone.

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.

If people want change, then they will find a way to get that change. So, whatever technology they may or may not have used was neither a necessary nor sufficient case for getting to the outcome that they got to, but having people who wanted change was.

Move fast, take risks, it's okay to try big things you're better off trying something and having it not work and learning from that than having not done anything at all.