People love photos. Photos originally weren't that big a part of the idea for Facebook, but we just found that people really like them, so we built out this functionality.

Facebook was not originally created to be a company. It was built to accomplish a social mission - to make the world more open and connected.

Facebook is really about communicating and telling stories... We think that people can really help spread awareness of organ donation and that they want to participate in this to their friends. And that can be a big part of helping solve the crisis that's out there.

I mean, we've built a lot of products that we think are good, and will help people share photos and share videos and write messages to each other. But it's really all about how people are spreading Facebook around the world in all these different countries. And that's what's so amazing about the scale that it's at today.

The main Facebook usage is so big. About 20 percent of the time people spend on their phone is on Facebook.

The thing that we are trying to do at facebook, is just help people connect and communicate more efficiently.