I was fascinated with jeans, because you can impress your life upon the jeans you wear. The way you sit imprints on the jeans.

The interesting products out on the Internet today are not building new technologies. They're combining technologies. Instagram, for instance: Photos plus geolocation plus filters. Foursquare: restaurant reviews plus check-ins plus geo.

There's an entire universe in every single tweet, and it all really depends on the content as far as how it's going to spread.

I think Twitter is the future of communications and Square will be the payment network.

Twitter is the world.

You don't have to start from scratch to do something interesting. You don't have to start from scratch to have a massive impact on the world. You have to have a good idea. You have to convince other people of those good ideas. And you have to push as quickly as possible.

Build what you want to see in the world.