Interactive television

Interactive television (also known as ITV or iTV) is a form of media convergence, adding data services to traditional television technology. Throughout its history, these have included on-demand delivery of content, as well as new uses such as online shopping, banking, and so forth. Interactive TV is a concrete example of how new information technology can be integrated vertically (into established technologies and commercial structures) rather than laterally (creating new production opportunities outside of existing commercial structures, e.g. the world wide web).

Interactive television represents a continuum from low (TV on/off, volume, changing channels) to moderate interactivity (simple movies on demand without player controls) and high interactivity in which, for example, an audience member affects the program being watched. The most obvious example of this would be any kind of real-time voting on the screen, in which audience votes create decisions that are reflected in how the show continues. A return path to the program provider is not necessary to have an interactive program experience. Once a movie is downloaded for example, controls may all be local. The link was needed to download the program, but texts and software which can be executed locally at the set-top box or IRD (Integrated Receiver Decoder) may occur automatically, once the viewer enters the channel.

The first patent of interactive connected TV was registered in 1994, carried on 1995 in the USA. It clearly expose this new interactive technology with content feeding and feedback through global networking. User identification allows interacting and purchasing.

The viewer must be able to alter the viewing experience (e.g. choose which angle to watch a football match), or return information to the broadcaster.

This "return path," return channel or "back channel" can be by telephone, mobile SMS (text messages), radio, digital subscriber lines (ADSL) or cable.

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