The BBC is to launch a range of web-based on-demand TV and audio services which could revolutionise the way people watch television.
The BBC Trust, which oversees the corporation, said today it had approved the service after examining the public demand and any impact it would have on commercial rivals.
The BBC said the new iPlayer system would allow viewers to catch up with programmes 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.ukwebsite, 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.
Broadcaster Channel 4 said today its on-demand service had been used by "well over" one million people watching a total of 20 million programmes since it was launched six months ago, far exceeding expectations.
The BBC, which will provide the content for free, dominates the broadcasting and radio industry in Britain and the media regulator Ofcom had warned that its entry into a nascent market such as on-demand could harm the competition.