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.

You can be so bad at so many things... and as long as you stay focused on how you're providing value to your users and customers, and you have something that is unique and valuable... you get through all that stuff.

People have really gotten comfortable not only sharing more information and different kinds, but more openly and with more people - and that social norm is just something that has evolved over time.

Virtual Reality is going to be an important technology. I am pretty confident about this.

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.

A squirrel dying in front of your house may be more relevant to your interests right now than people dying in Africa.

I hope that Facebook and other Internet technologies were able to help people, just like we hope that we help them communicate and organize and do whatever they want to every single day, but I don't pretend that if Facebook didn't exist, that this wouldn't even be possible. Of course, it would have.