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?"

I think we definitely want to focus on the simplicity aspect because it's something that's built into the culture even here at Twitter. Constraints inspire creativity.

A personal belief is that if you're not personally invested in what you're working on, you'll fail.

When you think of a social network, you have these two-way interactions: "Are you my friend? Yes? No? Yes?" Like LinkedIn, it's business oriented, but it's all about establishing connections. You connect to me through my other connections, and that sort of thing, and you sort of define who your friends are. Twitter doesn't have that.

Both my wife and I have a lot of compassion for animals in general.

I've probably overused this analogy of a flock of birds moving around an object in flight, but, in reality, it's so simple, real time communication of individuals that allow for this super organism type of organism to happen.

Embrace your constraints.