Facebook is inherently viral. There are lots of sites that include a contact importer, and for lots of them it doesn't really make sense. For Facebook it fits so well. It wasn't until a few years in that we started building some tools that made it easier to import friends to the site. That was a huge thing that spiked growth.

Our strategy is very horizontal. We're trying to build a social layer for everything. Basically we're trying to make it so that every app everywhere can be social whether it's on the web, or mobile, or other devices.

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

We are working hard to build a service that everyone, everywhere can use, whether they are a person, a company, a president or an organisation working for change

You could probably go all the way back to the first books. I bet people said 'why should you read when you could talk to other people?' The point of reading is that you get to deeply immerse yourself in a person's perspective. Right? Same thing with newspapers or phones or TVs. Soon it will be VR, I bet.

I think that people just have this core desire to express who they are. And I think that's always existed.

When you think about it, there's no way to input things into a computer. It's all... the holes only go out, right? Like you can plug a keyboard or a mouse in but that's a trick because the computer thinks the inputs are outputs. That's a programmer trick, basically magic. The key to the future is to make holes that go in too.