The world is very disparate, in terms of the US using the most energy per person, and then the other rich countries - Europe, Japan, New Zealand - using about half of what we do, and then the world average being about a fifth of what we use, with China just now surpassing the world average.

There are no significant bugs in our released software that any significant number of users want fixed.

Don't wallow in failure. Instead, learn from it.

We have two other countries, Pakistan and Afghanistan - again it's the instability that is a problem there. So over the next several years, we expect to drive the number of [polio] cases back down to zero because that is likely to be the second disease after smallpox that we completely eradicate.

By 2035, there will be almost no poor countries left in the world.

[We in Microsoft] are not the only software company but we are a great software company doing some unique work.

The most important work I got a chance to be involved in, no matter what I do, is the personal computer... I even knew not to get married until later because I was so obsessed with it. That's my life's work.