Ethan Zuckerman

When you sign up for Facebook, the service first searches for any mentions of your name and suggests you befriend anyone who has mentioned you in their posts. It then asks to access your e-mail account so you can connect with anyone with whom you regularly correspond.

What do cells do when they see a broken piece of DNA? Cells don't like such breaks. They'll do pretty much anything they can to fix things up. If a chromosome is broken, the cells will repair the break using an intact chromosome.

When people said Africa would change me, I didn't understand what they meant. To see the poverty in the townships, for instance, is overwhelming. I found it heart-wrenching to see young children walking barefoot and hungry in the dirt. I'm the kind of person who wants to change the world right here and now, so I got frustrated.