The Web represents the application of hypertext technology and a graphical interface to the Internet to retrieve information that is contained in specially formatted documents that may reside in the same computer or be distributed across many computers around the world. It consists of three main elements. The result is called the Web because it is made up of many sites, all linked together, with users traveling from one site to the next by clicking a computer's pointing device on a hyperlink. Each Web page can contain many screens or printed pages of text, graphics, audio, and even video, and the starting point for any Web site is called its home page. Although each page is an Internet site, it must be accessed via a special program called a Web browser, which can translate the HTML into the graphical images, text, and hypertext links intended by the creator of the page.
Interactive television is a generic term for a variety of technologies and products.
Typically, a home television receiver and a telephone line are connected through a small appliance that accesses the Internet through the telephone line and converts the downloaded Web pages into a form that can be displayed on the receiver. A remote control interface allows the user to navigate through the Web and select the information to be displayed. Ted Nelson, an American computer consultant, had promoted the idea of linking documents via hypertext during the 1960s, but the technology required was not to be available for another 20 years. This culminated in the introduction of a text-only interface, or browser, to the scientific community in 1990 and to the public in 1991. Because of the difficulty of using this version, acceptance outside the scientific and academic communities was slow.