Ofcom has launched a campaign to help parents keep their children safe when surfing the internet.

The campaign follows research by the telecommunications regulator, which found that two-thirds of five- to seven-year-olds, more than three-quarters of eight- to 11-year-olds and more than four-fifths of 12- to 15-year-olds use the internet at home.

The advice has been released to coincide with the start of the summer holidays, which Ofcom said would see children spending a lot more time surfing the web.

Previous research from security companies such as Webroot found that nearly two-thirds of children spent more than three hours a day surfing the web. The security company said parents were often unaware about how much time their children spent online; three-quarters of parents in this survey claimed that their children spent only two hours or less.

Ofcom has put together 10 tips to help parents ensure their children surf the internet safely.

These include talking to children and having a look at some of their favourite sites. It also recommends helping children to understand how search engines work so that they don't stumble across unsuitable content.

Ofcom also recommended that parents made sure their children aware that there are things on the internet which may upset them and that they can always talk to them – or another trusted adult.

These tips and information on further resources such as contact details for Get Safe Online and the Internet Watch Foundation. These are included in a consumer guide on the Ofcom website, which can be downloaded.

Parents can also watch a step-by-step guide on how to use parental controls on a computer using. The advice also includes setting parental controls for digital TV services such as Sky, Virgin Media and BT as well as some Freeview boxes. Parents can also learn about setting up parental controls on a PC through Windows XP and Vista as well as on a Mac.