Windows 8 is key to the future, the Surface computer.

We all learn best in our own ways. Some people do better studying one subject at a time, while some do better studying three things at once. Some people do best studying in structured, linear way, while others do best jumping around, surrounding a subject rather than traversing it. Some people prefer to learn by manipulating models, and others by reading.

I think we knew that this would be just like raising the kids together, this would be a fun thing to do in partnership. And you know, we're so lucky because we get to hire in very smart people. We get to partner with governments like the Canadian Development Organization - CIDA, USAID - tonnes of scientists doing this work. This is fascinating.

Nobody spends any money on smallpox unless they worry about a bio-terrorist recreating it.

The returns from investing in poor people are just as great as the returns from investing in the business world... and have even more meaning

I do think this next century, hopefully, will be about a more global view. Where you don't just think, 'Yes, my country is doing well,' but you think about the world at large.

We have over 60 million machines that can take the same diskette, plug it in and immediately ah, that that software's working. And so it's created the worldwide software industry that... that is so very competitive and moving so quickly.