By Ian Youngs Entertainment reporter, BBC News

Channel 4 has become the first major UK TV channel to be simulcast on the internet, allowing viewers to watch programmes on the net at the same time as they are broadcast on TV.

Most of Channel 4's homegrown shows are available on the simulcast

Channel 4 News host Krishnan became part of broadcasting history on Monday when he hosted his lunchtime bulletin.

Not only was it available on your common or garden TV set, it was also the first show broadcast live on Channel 4's website as part of the channel's new internet presence.

It is one of a number of significant developments from major broadcasters, which are shaping the way we will watch TV in the future.

The BBC and ITV are testing 24/7 simulcasts of their own and the corporation is already showing live internet broadcasts of the World Cup matches to which it owns the rights.

A total of 325,000 people tuned in to watch the BBC's three World Cup matches online on 13 June, the most popular day so far.

Live streaming is one way to offer TV over the internet. The other is to shows on demand - to watch when you want.

Desperate Housewives is among the shows available on iTunes in the US

Channel 4 is also offering episodes of Lost to download for 99p, and will open a more extensive TV download store this autumn.

This follows the lead of the US, where fans can already buy and download hundreds of programmes, including Desperate Housewives and The Office, for $1.99 (�1.09) on iTunes.

Sites such as Google Video are also beginning to offer commercial downloads.

But there are concerns about the video quality of the downloads being offered and the copy protection restrictions that are put in play to prevent piracy.

But as well as downloading shows to watch on a computer, services offering on-demand shows on a TV set are set to boom.

The BBC is planning its iPlayer, a free service allowing viewers to watch programmes on the web up to a week after they have been shown on TV, with the possibility of paying to watch them after that week is up.

HomeChoice already delivers video on demand straight from your broadband connection to your TV via a set-top box, while BT and Orange are planning similar high-profile services.

Viewers can now watch anything from live news and horse racing to sitcoms and cartoons on their mobile phones, while other pieces of kit are helping people choose where and when to watch.

Falling audiences

The use of personal video recorders (PVRs) - which record programmes onto a hard disk - is increasing.

And a new device called a Slingbox can transmit the TV signal from your living room to a computer or mobile phone anywhere in the world.

Stuart Collingwood, Sling Media's vice president Europe, says: "All the content owners are going to have to embrace multiple platforms.

"They're acknowledging that people want to access content where it suits them."

All these developments are being driven by a variety of developments, which are all pushing TV in the same direction.

On-demand - watching what you want when you want - will become increasingly important Guy Bisson Screen Digest

Firstly, the major TV channels are losing viewers and advertisers to digital broadcasters and the internet - meaning they have to find new ways to attract audiences.

The advance of technology means new methods of transmission are now possible, while the public is demanding increased variety, flexibility and control.

"On a European basis and even on a worldwide basis, most of the major broadcasters are rapidly developing some sort of online strategy," says Guy Bisson, senior TV analyst for industry journal Screen Digest.

"That may be simulcast, it may be limited catch-up service, it may be adding a paid-for element to an otherwise free channel, it may be adding a video-on-demand element.

"There are all sorts of opportunities here for channels which are finding their core revenue stream is being dented to bolster that revenue stream with new business models and new audiences."

People will still watch TV sets in their living rooms in 10 or 15 years, and shows will still be delivered by a variety of methods - not just the internet - he says.