The thing I really care about is the mission, making the world open.

Betting completely on HTML5 is one of the, if not THE biggest strategic mistake we've made.

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.

I made so many mistakes in running the company so far, basically any mistake you can think of I probably made. I think, if anything, the Facebook story is a great example of how if you're building a product that people love you can make a lot of mistakes

Advertising works most effectively when it's in line with what people are already trying to do. And people are trying to communicate in a certain way on Facebook - they share information with their friends, they learn about what their friends are doing - so there's really a whole new opportunity for a new type of advertising model within that.

I like to pride myself on thinking pretty long term, but not that long term.

Find that thing you are super passionate about. A lot of founding principles of Facebook are that if people have access to more information and are more connected, it will make the world better; people will have more understanding, more empathy. That’s the guiding principle for me. On hard days, I really just step back, and that’s the thing that keeps me going.