Any version of Windows is going to have lots of great new things that people use and things that are tough.

(On being the world's richest man) I wish I wasn't ... There's nothing good that comes out of that. You get more visibility as a result of it.

You know, development sometimes is viewed as a project in which you give people things and nothing much happens, which is perfectly valid, but if you just focus on that, then you'd also have to say that venture capital is pretty stupid, too. Its hit rate is pathetic. But occasionally, you get successes, you fund a Google or something, and suddenly venture capital is vaunted as the most amazing field of all time. Our hit rate in development is better than theirs, but we should strive to make it better.

For all these infectious diseases, the goal is to eventually get rid of them. And to do that we need to invent new tools, but nobody was doing that because there was no money to buy on behalf of the poorest, even the existing tools.

In poor countries, we still need better ways to measure the effectiveness of the many government workers providing health services. They are the crucial link bringing tools such as vaccines and education to the people who need them most. How well trained are they? Are they showing up to work?

To succeed, you also have to know how to make choices and how to think more broadly.

Security guys break the Mac every single day. Every single day, they come out with a total exploit, your machine can be taken over totally.