Social media is everywhere but do you think you know enough about who can see and use the images and information you send or upload?
A project called Growing Up Digital spent a year looking into how children use the internet and whether you feel you know enough about the websites and apps you use.
It's been done by the Children's Commissioner for England, whose job it is to understand what children think about the things that affect them.
Her report found that kids are left to learn about the internet on their own and that it's not always easy to understand what happens to photos and information sent on social media. She also thinks that the rules you sign up to when you use apps are far too complicated to be understood.
The report says schools should give lessons to pupils on how to use social media, apps and websites safely, and teach them what their rights are. You've been telling Newsround what you think about this idea.