High-definition TV (HDTV) is being touted as the next big thing in broadcasting but what exactly is it and what does it mean for viewers?
High definition is coming - but what does it mean?
Q. What is high-definition television?
HDTV is a new format that promises improved pictures and audio, with widescreen broadcasts.
Q. I thought digital TV gave me the best picture quality? What is the difference between digital and HDTV?
Think of digital TV like a car and HDTV as a type of passenger.
Digital TV is the method of transmitting and receiving different television signals while HDTV is a format.
HDTV programming is received via digital TV - either through cable, satellite or terrestrial.
There are also plans to deliver HDTV via broadband connections.
Q. Why is HDTV better than current, or standard-definition, television?
Television signals broadcast in high definition have four to five times as much picture information than a standard television signal.
That extra information results in sharper pictures. According to BBC research, viewers can tell the difference once they have television screens sized 28 inches or 69cm or more.
HDTV broadcasts can also include audio recorded in 5.1 surround sound and are also in widescreen - which is suited to films and sport broadcasts.
Q. This all sounds great. So do I just switch on and sit back?
In order to receive HDTV you must have three things:
an HD-ready television set
a decoder (set top box) to receive the HD signals
a TV service offering high-definition programmes
Q. What kind of TV do I need?
HD compatible TVs sport this logo
HD television sets range in price and features but can now be bought from about £500. In order to simplify the range of features, HD TVs which meet agreed standards boast a black HD Ready badge.
The logo ensure that the TV supports the preferred picture quality of HD broadcasts and supports the correct connector needed to hook up to HD products such as set top boxes, games consoles and next generation DVD players - called HD-DVD and BluRay.
This connector is called a HDMI input and must also support a copy protection system called HDCP.
TVs with the HD Ready logo should have these features.
Q. Can I use my existing digital set top box?
No. Existing set-top boxes such as a Freeview box or a Sky Plus box will not work with HDTV.
Digital satellite company Sky and digital cable firm Telewest are both offering high-definition services and the necessary HD set-top box.
Both firms have an added monthly charge on top of existing subscription costs while Sky also charges a one-off fee for its set top box.
A high-definition service via Freeview - digital terrestrial - is currently in the testing stages.
But due to limitations on how much information can be sent via digital terrestrial TV is not likely that HD services via Freeview will begin until analogue services are switched off from 2008 to 2012.
Q. What can I watch in high-definition?
Programmes have to be recorded in high-definition in order to be broadcast and received in high-definition. The amount of content recorded in HD is small but growing.
Sky will be offering some films and TV content from the end of May.
The BBC will be delivering free-to-air HD content of some of its dramas and documentaries to Sky and Telewest from mid-2006.
Satellite viewers do not need a Sky subscription to watch the BBC HD content and can also buy a HD compatible set top box from manufacturers other than Sky.
The BBC will also be offering all of its football World Cup matches in high-definition.
Video gamers with an Xbox 360 or with plans to buy a PlayStation 3 later this year can also play their games in high-definition.
Q. Should I be worried if I only have a "standard" TV and digital service?
No. Standard TV broadcasts will continue for many, many years. None of the broadcasters have announced any plans to only deliver HD content in the future.