For example, you could ask the person to stop - tell them you don't feel comfortable sending sexual images of yourself.
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Grooming online When people are online, they can hide who they really are.
People like this can be very convincing and will try really hard to get you to do what they want.
If something doesn't feel right, it's a good idea to tell someone you trust.
So it's important to be really careful and not trust people online if you can't be sure who they are.
Sometimes the person might pretend to be like you and have the same interests or problems as you.
Many different kinds of people have used the internet to trick, force or persuade young people into sharing sexual images of themselves.