In today’s terms, viewdata will look old fashioned and primitive. Many people will immediately associate it with teletext, which, while not an incorrect assumption, downplays the possibilities somewhat.
Teletext is a broadcast medium, especially suited to transmitting a relatively small set of fixed pages, usually of news and information, whereas viewdata can be much more comprehensive and far more interactive. Originally starting with the same aims: to offer information on demand, it quickly became apparent that simply because it is a computer in direct communication with it’s users, it would be quite possible to react to what those users want.
In the early days of Prestel, interaction was limited to “response frames” – a means where the IP (information provider) could present a page that the user could enter details into pre-prepared fields, which would then be “sent” to the IP (actually, stored until the IP went looking for them!) These were intended to be used for enquiry or order forms, and were often featured in videos promoting the services, booking theatre tickets or ordering cases of wine. I wonder whom the GPO thought their target audience was…
This was quickly developed into an electronic mail service (called, simply, “Mailbox”) whereby users could send messages to anybody, be that an IP or another user.
Some enterprising publishers automated the processing of their messages, publishing them back online so any user of the service could see them, and react in turn! Thus was born the chatline. In many ways similar to bulletin boards, and today’s Internet forums, there were specialist and general examples, moderated and unmoderated, free to use or pay-to-post, and all combinations thereof.
By utilising direct links, galled Gateways, from the Prestel network to their own systems, bigger businesses could offer even more interaction. Once you had your own computer directly communicating with your end-user, it could tailor the responses to their actions, generating information and pages on-the-fly and providing up to date information, personalised data, or pretty much anything you wanted. And you were not limited by how many pages you were renting from the GPO.
The travel industry embraced this rather thoroughly, with a myriad of services allowing travel agents access to instant availability and booking services, both directly and through Prestel or other third party networks. The Bank of Scotland launched their “Home and Office Banking” (HOBS) through Prestel. The Midland Bank had it’s own service users could dial directly. Littlewoods and Kays offered online catalogue shopping. British Rail linked their own private system through a Prestel gateway to allow the public access to timetables and other information. The possibilities were endless.
Anything you can think of doing on a computer, you could do through viewdata. The only limitation was the display format. If you do it on “the internet” today, you could probably do it though viewdata 30 years ago!
Here we will try to cover in detail a few of the facilities people found most useful.