Prestel — the UK’s pioneering Viewdata videotex service

Technical characteristics

The system used the public switched telephone network to connect users to centralized databases. Customers either bought a dedicated Prestel terminal or used a small adapter attached to a TV and a keyboard; later, software for personal computers enabled access as well. Pages were composed of character cells with restricted graphic capability, making the service efficient for the low-bandwidth modems of the era but limited in visual sophistication compared with later graphical networks.

History and development

Developed in the late 1970s by the Post Office as part of experiments with electronic information services, Prestel moved into commercial operation in 1979. It was one of several national videotex efforts worldwide, alongside systems such as France's Minitel. Over the following decade the service grew modestly and was later incorporated into the telecommunications company British Telecom; the platform was eventually sold by BT in 1994. At its peak Prestel had on the order of tens of thousands of subscribers, illustrating both early consumer interest and the limitations of pre-Internet technology.

Content, uses and examples

Prestel carried a wide range of information categories intended for home and business users. Typical offerings included:

• consumer information and shopping catalogues;
• news headlines and weather reports;
• financial quotations, stock market summaries and banking services;
• travel timetables, directories and public service notices.

Commercial organisations and public bodies paid to create pages, and interactive features such as simple forms and transaction requests foreshadowed later online commerce and banking.

Legacy and distinctions

Prestel is important as an early example of an online information service aimed at the general public. It demonstrated practical techniques for remote information retrieval over telephone lines and influenced the design of subsequent interactive services. It is often mentioned in the same context as other videotex projects and early online communities that set the stage for the rise of personal computing and the Internet.

Further information

For historical context and technical descriptions consult postal and telecommunications archives, contemporary accounts and technical surveys of videotex systems. Related resources include material about the transfer to BT, terminal hardware and adapters (computer interfaces and television adapters), dial-up networking over the telephone system and contemporary accounts of user experience via early online services.