You've probably learned a long list of important safety and privacy lessons already: Look both ways before crossing the street; buckle up; hide your diary where your nosy brother can't find it; don't talk to strangers.

The Federal Trade Commission, the nation's consumer protection agency, is urging kids to add one more lesson to the list: Don't post information about yourself online that you don't want the whole world to know.

The Internet is the world's biggest information exchange: many more people could see your information than you intend, including your parents, your teachers, your employer, the police -- and strangers, some of whom could be dangerous.

Social networking sites have added a new factor to the "friends of friends" equation. By providing information about yourself and using blogs, chat rooms, email, or instant messaging, you can communicate, either within a limited community, or with the world at large.

But while the sites can increase your circle of friends, they also can increase your exposure to people who have less-than-friendly intentions. You've heard the stories about people who were stalked by someone they met online, had their identity stolen, or had their computer hacked.

For more information on digital safely, please visit NetSmartz.org.