When you say that after World War I there was a pandemic that killed more people than the war itself, most will say: "Wait, are you kidding? I know World War I, but there was no World War 1.5, was there?" But people were traveling around after the war, and that meant the force of infection was much higher. And the problem is that the rate of travel back then was dramatically less than what we have nowadays.

During the past two centuries, innovation has more than doubled our life span and given us cheap energy and more food. If we project what the world will be like 10 years from now without continuing innovation in health, energy or food, the picture is dark.

Take agriculture, where we haven't done much, or sanitation; saying, "okay, we will be able to make a really huge effort there." It really energized the foundation and half of what we've gotten done in this last decade is because Warren [Buffett] trusted us.

You may have heard of Black Friday and Cyber Monday. There's another day you might want to know about: Giving Tuesday. The idea is pretty straightforward. On the Tuesday after Thanksgiving, shoppers take a break from their gift-buying and donate what they can to charity.

Depending on where you live, cooking, sex and pooping are either 3 of life's pleasures or what kills you

If your goal is to make the world a better place, one thing you can do is pick a specific challenge that you really care about. Then, learn as much as you can about it and try to volunteer your time to help an organization that is working in this area. While you're doing that, look for creative new ways to use technology to tackle parts of the problem that you come in contact with.

DOS is ugly and interferes with users' experience.