Understand that you dont have all the answers, you just have to start somewhere and keep an open mind.

At Twitter, mobile is in our DNA ... For us, it's all about mobile, and it always has been.

You have to have an emotional investment in what you're doing. If you don't love what you're doing, failure is pretty much guaranteed.

In any leadership position, you're always going to be disappointing somebody.

It's important to credit the brave people that take chances to stand up to regimes. They're the star.

I started designing book jackets, which was great because I was good at it. And then from there I decided to become a freelance graphic designer and I needed to expand beyond book jackets, so I taught myself web design, and then in 1999 some friends of mine decided to start a company called Xanga.com, which was a very early kind of social network slash blogging community.

Lesson number one: opportunity can be manufactured. Yes, you can wait around for the right set of circumstances to fall into place and then leap into action but you can also create those set of circumstances on your own. In so doing, you manufacture your own opportunities. This has helped me immeasurably.