Social network websites are ways of linking people who share interests and activities over the internet.

Many parents remain in the dark about sites such as Facebook and Twitter, how their children are using them and the security issues involved.

Used safely, social networking sites are a fun way to stay in touch with friends and discuss shared interests. But without proper precautions children can be exposing details of their lives to anyone who logs on.

As adoptive mum Molly warns: "Be very careful about what information is out there."

Sharing personal information

Social networking websites allow users to create a profile of themselves, including information about them, their interests and activities, contact details and a photograph.

They can decide how much or little information to give, and adjust privacy controls to choose who can view their profile or contact them.

For example Jenny, aged 14, decides to set up a profile on Facebook. She uploads a photo of herself, writes about her interests, enters her email address and mobile phone number and gives her home town as 'Bristol'.

Jenny can choose whether only people she knows and has confirmed are her 'friends' can see her details, or she can choose to leave her profile open – allowing anyone who searches for her to look through this information.

Even if she chooses that only friends should see her full profile, unless she restricts how her details appear when people search the site, if someone searches for her, they will be able to see her name, photo and the names of any 'networks' to which she belongs, such as 'Bristol'.

The risks

Molly and her family did not use Facebook, but information placed on it by other people still meant they could be traced by her son's birth family.

Her son Fred, eight, had face to face contact with his two brothers and letterbox with his birth parents. He was considered too traumatised for direct contact with his birth parents and was adopted out of their authority, to avoid accidental meetings.

During contact he let slip his new surname, and this enabled his brothers to track down photos of Molly on Facebook, posted by her college students despite her requests, and which the brothers recognised from the contact visit.

They passed this information on to their birth parents, who found the family's address on 192.com.

Molly explained: "Then the phone calls started. It caused a lot of trauma really. Fred started to ask why am I here and my brothers there?"

Where to go for help?

For general guidance on internet safety for children and young people:

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