I don't think of Twitter as a social network. I think of it as a messaging system that has a lot of social components to it.

I started as an artist and I had a side job moving some heavy boxes for a publishing company. They had just gotten a Mac for their art department, the department that creates the book covers. I was kind of showing the art director a thing or two about how to use a Mac. And one day everyone went out to lunch and I jumped on the computer and designed a book jacket and slipped it in the pile to go to the review board in New York. They picked my jacket and when the art director got back to Boston, he wanted to know who designed it and I said, "Me." He was like, "The box guy?"

The two things I use the most are the MacBook Air and my iPhone. Those are my two most-used gadgets that are dented, scratched and smashed.

Positive culture comes from being mindful, and respecting your coworkers, and being empathetic.

Investors are employees you can never hire. We made sure to pick investors that thought like us.

You can shut down a service, and yet people will find ways to communicate.

I think Twitter has brought something totally new to the table.