Video on Demand (VOD) are systems which allow users to select and watch
to video content on demand. IPTV technology is often used to bring video on demand to televisions and pcs
Television VOD systems either stream content through a set-top box, a computer or other device, allowing viewing
in real time, or download it to a device such as a computer, digital video recorder (also called a personal video
recorder) or portable media player for viewing at any time. The majority of cable- and telco-based television providers
offer both VOD streaming, including pay-per-view and free content, whereby a user buys or selects a movie or television
program and it begins to play on the television set almost instantaneously, or downloading to a DVR rented from the provider,
or downloaded onto a pc, for viewing in the future. Internet television, using the Internet, is an increasingly popular form
of video on demand.
Some airlines offer VOD as in-flight entertainment to passengers through individually-controlled video screens embedded
in seatbacks or armrests or offered via portable media players. Airline VOD systems offer passengers the opportunity to
select specific stored video or audio content and play it on demand including pause, fast forward, and rewind.