In television technology, widescreen signaling (WSS) is a digital stream embedded in the TV signal describing qualities of the broadcast, in particular the intended aspect ratio of the image. This can be used by a widescreenTV to switch to the correct display mode. A digital system is one that uses discrete values rather than a continuous spectrum of values: compare analog. ... The aspect ratio of a two-dimensional shape is the ratio of its longest dimension to its shortest dimension. ... A 32inch CRT widescreen television A widescreen image is a film image with a greater aspect ratio than the ordinary 35 millimeter frame. ... Television is a telecommunication system for broadcasting and receiving moving pictures and sound over a distance. ...
References
ETSI EN 300 294 "Television Systems: 625-Line Television Wide Screen Signaling (WSS)"
A widescreen image is a film, computer, or television image with a wider aspect ratio than the standard Academy frame developed during the classical Hollywood cinema era.
Widescreen was first widely used in the late 1920s in some shorts and newsreels, including Fox Grandeur News and Fox Movietone Follies of 1929, both released on May 26, 1929 in New York City in the Fox Grandeur process.
One rationale for widescreen is that, since the human eye has a field of view that extends farther to the sides than it does above or below, a widescreen image makes more effective use of the field of view, thereby producing a more immersive viewing experience.