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.

Viewdata and teletext shared the same display layout and technology thanks to an unusually sensible agreement between the developers in the early days, when it was expected that both would be principally displayed on a domestic television, however teletext is a broadcast medium, especially suited to transmitting a relatively small set of fixed pages, usually of news and information, whereas viewdata, which has no limits on number of pages, 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 very easy to to react to what those users want and provide much more personal and interactive content.

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 envisaged as 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 to another user.

Some enterprising publishers automated the processing of their messages, publishing them on their own pages 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 as with 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 – this was used by, for example, British Rail, to provide access to all their rail timetables – something that would have been prohibitively expensive to publish directly on Prestel itself.

The travel industry embraced the viewdata concept rather thoroughly, as holiday pricing and availability could fluctuate minute by minute, and being able to give travel agents direct access to the computer systems without having to provide a large call centre and hoards of telephonists was incredibly enticing.   This is the one area where there are still, to this day, viewdata services operating, although this is possibly through lethargy and a belief in “if it works, don’t touch it,” rather than their not being better tools for the job these days!  In viewdata’s heyday, there were hundreds of services allowing travel agents access to instant availability and booking services, both by providing direct access to their own servers, through Prestel gateways, or through 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. Even within BT, there ended up a completely separate viewdata service for accessing the “Electronic Yellow Pages.” The possibilities were endless.

Pretty much anything you can think of doing interactively 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.