Britain’s publicly-funded broadcaster the BBC is to launch a range of web-based on-demand TV and audio services which could revolutionize the way people watch television.

The BBC Trust, which oversees the corporation, said on Monday it had approved the service after examining the public demand and any impact it would have on commercial rivals.

Broadcaster Channel 4 said on Monday that its on-demand service had been used by “well over” one million people watching a total of 20 million programs since it was launched six months ago, far exceeding expectations.

The BBC said the new iPlayer system would allow viewers to catch up with programs from the previous seven days and store them on a computer for 30 days, while cable viewers will be able to use this service on their televisions.

IPlayer, which will be located on the www.bbc.co.uk Web site, will also allow viewers to watch programming on the Internet and listen to some audio downloads without anti-piracy software known as digital rights management.