Facebook is inherently viral.

On engagement, we're already seeing that mobile users are more likely to be daily active users than desktop users. They're more likely to use Facebook six or seven days of the week.

There have been misperceptions that we're trying to make all the information open on Facebook, and that's completely false. There are big buckets of information that we recommend that you share with only your friends privately. Then some of the more basic information, we recommend that that's visible to everyone.

In a lot of ways Berlin is a symbol for me of Facebook's mission: bringing people together, connecting people and breaking down boundaries.

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

It is really important for us that people understand what the strategy is and that the real approach is to make everything social, not to build a vertical approach.

A guy who makes a new chair doesn't owe money to everyone who ever built a chair.