HDTV leverages a set of standards referred to as Digital Television or
DTV. DTV consists of a set of eighteen different standards for
transmitting television signals. Digital television differs
significantly from the analog system that has been used since
TV was introduced in the 1950s.
Digital Television should not be confused with High Definition
Television. Many cable and satellite companies simply convert
standard analog television broadcasts to digital to improve
reception and to provide additional services. These
transmissions are not high definition, however, as the picture resolution is not HDTV quality and the picture format is not
wide-screen. Approximately two-thirds of HDTV owners in the United States subscribe to a
digital service today.
Digital Television (both non-HDTV and High Definition)
can provide the following benefits over the old analog system:
- Improved picture quality on conventional channels
- CD quality audio reception
- More television stations availability
- Onscreen program guides
- Video on-demand services (VOD)
- Pay-per-view services (PPV)
- Interactive services
- Parental control features
- Music services
Video on-demand services available from cable and
satellite TV service providers include:
- movies on-demand (MOD)
- subscription video on-demand (SVOD) - e.g. HBO on-demand
- free video on-demand (FVOD)
To receive Digital Television, the viewer normally requires a set-top box
that connects the television set to the cable outlet or satellite dish.
Some (but not all) digital boxes can support High Definition broadcasts.
