The word "broadband" has been bandied around a lot over the past year but what is it and what does it do?

I asked BT's technical experts to explain.

What is broadband?

Broadband refers to services that provide high-speed communications, usually to access the internet.

Large companies have been using high-speed services for years but the development of cheaper technologies means broadband is now an affordable option for homes and smaller businesses.

Broadband lets you transfer large amounts of data, such as email attachments, video or Digital music, far more quickly than using a standard modem and phone line or even Integrated Services Digital Network (ISDN).

The term broadband encompasses a range of technologies including cable, mobile, satellite and Asymmetric Digital Subscriber Line (ADSL) technology.

It has come to stand for faster, cheaper, always-on internet access.

Who has it? Last month, telecoms watchdog Oftel said the take-up of new broadband subscriptions had risen to almost 30,000 per week and that the UK had more than 1.4 million broadband users.

Its research also indicated:

One in ten of UK homes with internet access use broadband services.

The average household spends about nine hours a week online.

Nine out of ten households are satisfied with the service they get from their internet service provider.

The benefits of broadband.

The faster speeds available from broadband mean users can go online more often, stay online for longer and use more services.

Like electricity or tap water, broadband is always on. You need never dial-up to the internet again.

Access to the internet is immediate and email is likely to arrive as soon as it is sent.

Internet pages containing large files, pictures or multimedia packages can be downloaded in seconds.

You can also make ordinary phone calls or use the fax machine while you are online without needing a second line.

Users pay a fixed rate so you can be online all day, every day for a monthly subscription fee.

The combination of speed, a permanent connection and interactivity has the potential to transform the way we live, learn, work and communicate.

How to get broadband?

ADSL broadband is available to 70 per cent of the population in Sussex. There are two main ways to sign up for broadband - via ADSL, which runs over your existing phone line or via cable modem.

The first step to ADSL is to find out if it is available in your area, which will depend on how far from the telephone exchange you are and what quality of telephone line you have to your premises.

If you live outside the existing catchment areas for ADSL broadband, BT Wholesale has launched a demand registration scheme.

This allows you to register via your preferred service provider if you would like ADSL broadband in your area.

For example, the Selsey exchange has a trigger level of 350 registrations to indicate demand that is needed to make it viable for upgrading.

As soon as this is reached, BT Wholesale will put broadband into that exchange, bringing the service to a further 5,500 homes and businesses.

A list of participating service providers can be seen on www.bt.com/broadband, as can the level of demand already registered in each area.