Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Viewdata is a Videotex implementation. It is a type of information retrieval service in which a subscriber can access a remote database via a common carrier channel, request data and receive requested data on a video display over a separate channel. Samuel Fedida was credited as inventor of the system. The access, request and reception are usually via common carrier broadcast channels. This is in contrast with teletext.

Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.