Police Scotland is urging young people to be wary of who they send pictures or explicate messages - known as 'sexting' - to as they could go viral.
Officers have warned school children against sending out images that they wouldn't pass around school or show their mum or dad.
The force has launched a new campaign called Stay Safe Online which they hope will raise awareness of the risks and help children, parents, teachers and carers improve their knowledge and understanding of how to keep children safe.
The new campaign features a hard-hitting video involving pupils aged 13 to 16 from Clyde Valley High School in Wishaw, North Lanarkshire, who recount their personal online experiences.
Superintendent Stevie Wilson of the specialist crime division, based in North Lanarkshire, said: "We want teens to think about what they share; and to think about the consequences as thousands of school children are being bullied, blackmailed or harassed because photos they thought were private, became viral and went public.
"All children and young people need to understand they should only share pictures online that they are happy with friends, family and others seeing.
"They also need to know how to keep their personal information private and to contact an adult if they feel threatened.
"Any child who feels at risk or is worried should speak to a parent, guardian or teacher or they can phone Police Scotland on 101 or ChildLine on 0800 1111."
As part of the campaign, Police Scotland has published tips for 13 to 16-year-olds. These include:
l Keep your phone, laptop or tablet secure and use a password or PIN.
l Don't do anything online that you wouldn't do face to face.
l Think about what you post, would you be happy for people to still see it in 10 or 20 years? Comments, photos and videos share make up your digital footprint, even if you delete it, so there is still a record of it.
l Never feel forced into doing anything you don't want to do.
l Never arrange to meet someone who has contacted you on the internet.