The latest version of the Opera web browser promises to be a boon for anyone wanting to download large files from the internet. This is because of its support for a technology called BitTorrent that is used to share files.

Rather than downloading a file from one computer, BitTorrent splits the download between several computers across the internet saving time and resources.

BitTorrent has been around for some time but recently hit the headlines when the test version of Windows Vista was made available on a BitTorrent website.

Microsoft demanded that the website stop this, claiming that it was "offering unlicensed copies of, or is engaged in other unauthorised activities relating to, copyrighted works published by Microsoft".

Part of the controversy surrounding BitTorrent is that because the download comes from different computers, the original publisher of the file may not be involved, as was the case with Windows Vista.

BitTorrent techology is widely used in the Open Source community, but it also has a reputation for being used by software and movie pirates.

In one recent case, police in Sweden raided the offices of a website that gave out BitTorrent links. The reason given was that they were "on suspicion of breaking copyright law or abetting the breaking of copyright law".

A representative for the British Video Association refused to comment specifically on Opera but said that any peer-to-peer sharing technology was a concern.