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.

I've been going through photos of my mother looking back on her life and trying to put it into context. Very few people age gracefully enough to be photographed through their aging.