As a government policy, it's a vote-catcher on a par with Anne Robinson standing for the Welsh Assembly. No politician would dare be the one to turn off the nation's TV sets and leave viewers all over the country with blank screens.

The situation is not quite "the digital disaster" headlined by one national newspaper but it is causing as many furrowed brows as any Agatha Christie whodunit.

Around a third of households in the UK who have access to digital already, need not worry. They're ready for Culture Secretary Chris Smith to pull the plug on the analogue system most of us use at present to receive TV programmes. But sometime in the not-too-distant future the big switch from analogue to digital transmissions will happen, although probably not as early as the 2006 to 2010 time scale originally set by the Government.

They have to honour their pledge to keep the analogue signal switched on until 95 per cent of viewers who can receive the main free-to-view channels now can do so digitally. There's a promise too to help those on low incomes make the changeover.

All of this leaves the future of digital in doubt. The ITC (Independent Television Commission) notes in its annual report, published this week, that 2000 saw digital television taking off faster than any other recent technology has done. It reports that over 30 per cent of households have access to digital. This compares with Internet access in 33 per cent and 60 per cent mobile phone use. As with cable and satellite services, households with children and younger households are more likely to have adopted digital TV. Viewers over the age of 55 show a much lower level of interest. Nobody is doubting the advantages of digital TV which include clearer wide-screen pictures, better sound quality and interactive services such as home banking and shopping. But no politician can be seen to be forcing voters to change, especially as it may cost them money.

A recent Consumer Association report called the Government's plan "fatally flawed", claiming proposals to have all households on the digital system by 2010 were "unrealistic" and doomed to failure.

The survey found that a third of those without digital television said they would never get it. Two-thirds who don't have it, have not even considered switching to digital TV. Many weren't even aware of the Government's intention to shut down the present analogue signals.

None of this takes into account whether viewers actually want the extra channels - as many as 200 - that digital would be able to offer. That's because digital is able to squeeze several channels into the space used to carry a single analogue channel, creating opportunities for many more new channels and programme services. It will also free up channels for other purposes, such as mobile communications, to ease problems in the currently-overcrowded airwaves.

Despite greater choice and many more channels on offer, the ITC found that people aren't watching more TV. The average amount of time spent in front of the box last year remained three-and-a-half to four hours a day.

The digital confusion extends to people not even realising that as many as a dozen channels, such as BBC Choice and ITV2, are free on digital along with the existing five terrestrial channels BBC1, BBC2, ITV, Channel 4 and Channel 5. These UK free-to-view broadcasters have, in a rare spirit of co-operation, joined forces to remind viewers that they can more than double the number of channels they receive without paying subscription fees, by switching to digital.

These are some things you need to know to avoid switching off at talk of the big switch. There are three ways of accessing digital TV - an existing rooftop aerial, a satellite dish or a cable connection (for which you'll have to pay a subscription).

You will need a digital television set, preferably wide-screen for the best viewing experience, or a set-top box decoder. For services for which a charge is made, and for some free satellite services, you need a smart card to allow reception.

The main terrestrial channels will remain free-to-view on digital along with a dozen other channels. You will be able to add others by buying various packages of extra channels, costing from around £10 a month upwards. You can tailor what you buy to whether you want to watch sports, movies, children's channels or whatever. There is also pay-per-view - one-off events for which a separate charge is made.

TV Internet is available now on some systems, with all digital cable operators hoping to provide it soon. Digital satellite and digital terrestrial are also planning some form of Internet access. All offer a mix of e-mail, home shopping and information.

The chances are that once you have digital TV, you'll need help picking your way through the maze of programmes - which is where the EPG (electronic programme guide) comes in. Digital TVs have EPG to show what is on now and the rest of the day, plus allow you to search for shows by type. Who knows, once you master the technology you might even find time to watch a programme.