Privacy is no longer a "social norm," facebook CEO Mark Zuckerberg said last year. At first glance, it seems that Zuckerberg is right. More than half a billion people use his site to share all sorts of intimate details of their lives with others loosely defined as "friends." In your own life, you've likely noticed that people are broadcasting details that they used to reserve for small circles of friends. They announce when they break up with a romantic partner as casually as they mention what they are cooking for dinner or where they are shopping. Teens and twentysomethings seem particularly fond of such sharing, leading many people to conclude that younger people care little about privacy. But Zuckerberg is wrong, and the fact that you know what your cousin had for dinner doesn't change that. Privacy does matter to everyone, regardless of birth date. Even if you opt to tell many people when you are drunk or with whom you aresleeping, you care about privacy. It's not about what you share and where you reveal it. Privacy is about the fact that you have a choice in what you reveal and that you exercise the choice knowingly.