In the past 15 years, nothing has given entertainment publishers quite as many sleepless nights as internet piracy. Starting with the rise of Napster, the music-sharing service, in the 1990s, the rapidly increasing speed of broadband connections has allowed consumers to share and copy media files in vast quantities.

Music was the first to feel the lash of piracy, largely because each track is a fairly small file, taking only a minute or two to download even on the slower broadband of the mid90s. Today entire movies (hundreds of times larger than a music track) and videogames (thousands of times larger) can be transferred easily between computers anywhere in the world.

For the predominantly young and techno-savvy audience who use file-sharing services, this makes the internet a cornucopia of free, easily accessible media. Some enterprising artists and creators have tapped into that enthusiasm – but for most big media companies, this is nothing more than criminal behaviour on a huge scale.

Today’s announcement of widespread legal threats to file-sharers in Britain is just the latest in a long line of increasingly desperate attempts to hold back the tide of file-sharing. It mirrors similar efforts by the music and movie businesses in North America, where legal threats have been sent to thousands of people.

The general perception of a file-sharer is of someone in their 20s – the archetypal “computer hacker”. The reality is different: programs are so simple that many sharers are children. For their parents – the registered owners of the broadband line – receiving a legal letter accusing them of piracy will come as a shock.

It is common for a hoarding mentality to take root among those who use file-sharing services. Many download dozens of games they have no intention of playing, but they may swap them with friends to build up their collections further. Simply by storing these games on their computers while using a file-sharing service, they risk being taken to court.

Unfortunately, there is no easy solution to suggest to parents on how to avoid such legal threats. It may be an old chestnut, but the only way to know if your children are using file-sharing services is to talk to them and to learn more about the software they are using.

What if you get £300 bill?

— Seek specialist legal advice

— If you are satisfied that the company owns the rights to the game and that you have infringed those rights, then pull the game off the file-sharing site and write promising never to do it again

— Do not pay the £300 unless you consider the sum to be reasonable. Work out how much the game costs in the shops and multiply that by the number of people who downloaded it from you

— Consider how likely you are to be pursued. The figures suggest that you have a 2 per cent chance of being taken to court. But if you are, you could get a real hiding

— Davenport Lyon says that it will not usually take action against students or the unemployed, so if you are one, tell them

Rob Fahey is a computer games analyst

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