Sonali checks out Facebook privacy settings
There's a massive row going on about what happens to all the personal information and pictures you put up on social sites like Facebook and Bebo.
About a quarter of eight to 12-year-olds are signed up to social networking sites, even though most say you have to be 13 or older to have a profile.
Some people say the sites don't make it clear how to protect the stuff you post online and stop strangers seeing it.
But now the man who set up Facebook says he's made things a lot simpler.
There's been lots of pressure for the site to make it easier for you to decide who you want to share your details with.
Some people still don't think they've gone far enough, and want profiles to be automatically hidden so no-one can read stuff about you unless you decide they can.
There are about 400 million people on Facebook.
The advice is to check your privacy settings to make sure you've got them right.