Are you a teenager who spends too much time on Facebook, MySpace, or other social networking sites? If you do, be cautious. Because while such sites can be great for teens looking  to keep up with trends, they can also pose risks. Once you’re networking online, you expose yourself in lots of ways.

On the positive side, you can find supportive communities that make you feel more connected to the world at large. But on the negative side, you might find people out there in cyberspace who aren’t so nice. They might even be your so-called “friends.”

Cyberbullying—a new online realm for an old problem

These days, because teens spend as much time socializing online as they do in person, they have found ways to bully online. Kids can be cruel; it’s why high school can be so hard. Now the Internet has made it even easier for teens to spread their cruelty in new ways. Teenagers can send mean emails or post nasty comments on social networking sites. Unfortunately, the freedom to be able to communicate online also makes it really easy to be mean online.

Cyber “control”

In some teen relationships, abusive romantic partners use the Internet to maintain control over their partner, says Nancy Willard, executive director of the Center for Safe and Responsible Internet Use. “They are always keeping in touch with the person so that the controlled partner is always under the electronic control of the other person,” she says. She adds that “the risk of predation by an online stranger is low.” It’s the people you know, she says, who you most need to worry about.

Don’t show your stuff

Sometimes teens ask their partners to send them nude pictures. Just remember: once you send a picture of yourself into cyberspace, it can go anywhere. And it’s there forever. “Sometimes this creation [of nude pictures] is just a stupid courtship ritual,” says Willard. “But other times it can be more malicious.” It’s not uncommon for such photos to get passed around among friends or acquaintances. Do you really want to take that risk?

Meeting online

Then there’s the online relationship. You may “meet” someone through friends on a social networking site or on an online teen dating site. If you meet someone this way, keep in mind that you don’t really know who they are—you just know who they say they are. Plus, if you decide to actually meet someone you’ve only met online, it’s best to meet in a public place, with friends around—just in case things don’t go well or you feel uncomfortable.

You call this “community”?

Probably the most dangerous online threat to teens, says Willard, are questionable online communities. “These groups focus on self-harm or aggression against others,” she explains. Such web sites often target children and teens who feel marginalized. They may promote self-cutting, anorexia, drugs, or suicide. Or they may contain racist, homophobic, or anti-Semitic content.

Word is out

According to a 2009 survey, nearly half of all teens with a social networking profile have a public profile viewable by anyone, and one in four know someone who has had something bad happen to them because of information posted electronically.

Staying safe in cyberspace

With all these minefields online, it can be hard to steer clear.

What can teens do? The simplest advice is to think before posting anything online—comments, pictures, whatever—because it might come back to haunt you. “The core things to focus on are what kind of image are you putting out there and how are you interacting with others,” Willard says, “There used to be a saying ‘On the Internet nobody knows you’re a dog,’ but today on the Internet, not only does everybody know you’re a dog, they know what breed you are, where you hide your bones, your thoughts on the hot poodle down the street. It’s all out there.”

Tips for staying out of online trouble