(16:9) Widescreen - 16 units wide by 9 units high
This format for a television screen is based around cinema style and is used to describe the width of tv screen whether is be LCD or Plasma

Widescreen Signalling is an automatic process by which the screen format is switch from widescreen TV to 16:9 cinema style mode whenever a signal is detected from either a broadcaster, a VCR or a DVD player.

Screen Ratio Size
4:3 72x54
3:2 81x54
16:9 96x54
1.85:1 100x54
2.39:1 129x54

Widescreen TV information

A widescreen image is a computer, film, or television image with a broader and shorter aspect ratio with what was considered standard in the classical Hollywood cinema era.
Silent film was projected at a ratio of four units wide to three units tall, often expressed as 4:3 or 1.33:1. The addition of sound-on-film soundtracks and a thicker frame line in order to hide physical splices in prints caused the frame dimensions to standardize by 1932 to Academy format, which is actually 1.37 but often erroneously called 1.33. Widescreen was first widely used in the late 1920s in some shorts and newsreels.

Anamorphic widescreen is a video technique that utilizes rectangular (wide) pixels to store a widescreen picture into standard 4:3 aspect ratio. It was originally devised for widescreen television sets with a 16:9 aspect ratio but not in use before the advent of DVD and DVB.

Major digital television channels in Europe are often broadcast in anamorphic widescreen in standard definition. In almost all cases, there is also the ability for the channel to switch between 4:3 and 16:9 as necessary, depending on programming. Set-top boxes, including Sky Digiboxes have the ability to switch the television set to the correct aspect ratio by means of SCART. The main five terrestrial networks in the UK are broadcast in 16:9 on digital.