You may have your own Facebook profile or Bebo account that lets you chat with friends or communicate with other users who share your interests. These 'social networks' let you create your own blog, upload photos and videos for others to see and add people to an online friends list.
Social networks are a great way of keeping in touch but you should think carefully before adding someone to your list of online friends or posting a blog entry that could get you into trouble at school, college or work.
If you are looking for more information about staying in control of your page and how to get the most out of social networking sites, the ThinkuKnow website has all the advice you need.
If you're concerned about something that may have happened online, talk to a trusted adult, such as a parent, teacher or youth worker, or visit the CEOP advice and help centre.