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 you what your rights are.
We asked you what you thought...
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I think terms and conditions should be shorter so that kids will actually read them.
Sienna, 12, England
One lesson isn't enough to tell people about being safe online. Even if you are a grown-up you still need to learn how to be safe online. You should be safe online because if someone messages you, you shouldn't text them back if you do not know them. We need to learn a lot about being online as when we are older we will be using online a lot more.
Year 4G, Knockhall Primary School, England
We all know about setting our privacy settings to private. We think we are only sharing with people we know. Facebook shows you how to set your settings to private when you log in.
It (lessons) would be good as long as it wasn't boring. We get told the same things every year and it gets repeated, we want new information. Perhaps the police or a visiting person could show us rather than our normal teachers.
We don't think some people understand that once you've shared something, you have no control over what happens to it next. It could be sold or shared with people we don't want to see it.
Class Q and class DP, Somerset
Teachers have talked about it at my school but because we are at home they can't control what we do neither can the government. I know a lot of people lie about their age to get into an inappropriate website that might be for a 12+ so I keep myself safe by not doing this. A lot of my friends have all the more grown-up apps for their age like instagram, facebook and twitter.
George, 9, Watford
A good idea would be to only be able to send/receive friend requests from people you know. We know that we should set our accounts to be private to strangers, and block or report suspicious activity. Facebook should have the power to automatically delete inappropriate content immediately from anyone's account.
Maybe it would be a good idea to not publicize your phone number on your profile page, although it was pointed out that you can make this private on your Profile if you select the right option.
Buddy System - We recommend older children (secondary school age) would buddy with primary age (our age) to share their knowledge about the internet, privacy, safe use, terms and conditions.
Apps should need an adult approval to confirm the child's age.
Primary 6/7, West Lothian, Scotland
I think that all kids should be taught in school how to stay safe on the internet because there are many social games on the internet that strangers can go onto.
Natasha, 10, England
When I share things online I always make sure that it is appropriate and it won't be hurtful to people.
Jessica, 15, London
I think that the terms and agreements should be shorter because people normally just want to get on with what they are doing and not read lots of pages.
Leah, 10, Leeds
Thanks to my school I know a lot about social media. I now feel safe on the internet and I can safely get in touch with old school mates.
Alix, 13, Grantham