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===Growth===
From September 1986,<ref name=TelematicsTransition>
Prestel's publicity department published a "Factframe" on the database showing, at the end of each month, the average number of terminals attached and the percentage in businesses and homes; the number of frames available and the number of frame accesses per week; and the number of messages sent per week.<ref name=Factframe>An example from 1987:
{{
cite book
|title=Telematics in Transition: The Development of New Interactive Services in the United Kingdom
|first1=Graham
|last1=Thomas
|first2=Ian
|last2=Miles
|date=1989
|publisher=[[Longman]]
|location=[[Harlow]]
|isbn=978-0-5820-5595-7
|oclc=22706270
}}</ref>{{rp|27}} under page *656#, Prestel's publicity department published a "Factframe" showing, at the end of each month, the average number of terminals attached and the respective percentages in businesses and in homes; the number of frames available and the number of frame accesses per week; and the number of messages sent per week.<ref name=Factframe>An example from 1987:
{{
cite document
Line 335 ⟶ 348:
|first3=Volker
|last3=Schneider
|author-link3=:de:Volker_Schneider_Volker Schneider (Politikwissenschaftler)
|date=1992
|editor-first1=Harry
Line 386 ⟶ 399:
|title=Viewdata in Retail and Distribution
|author=Department of Trade & Industry
|author-link=Department of Trade and Industry (United_KingdomUnited Kingdom)
|date=1984
|page=8
Line 395 ⟶ 408:
}}</ref> 61% were business, and 39% residential. In that month, on average, the Prestel database contained 320,000 frames that were accessed 14.6 million times.<ref name=Rutter />{{rp|128}} For July, the Butler Cox [[management consulting|consultancy]] recorded 47,000 users (60% business, 40% residential), a total of 1,200 IPs and sub-IPs, and 17 external computers accessed via Prestel Gateway.<ref name=ButlerCox1985 />{{rp|26, Fig. 1.15}}
 
After another year, in mid-1985, ''[[The Times]]'' stated there were 53,000 "terminals, adapted televisions, microcomputers or specially designed units" attached to Prestel, with residential users havingnow risenaccounting tofor 45% of the total. In the reporter's view, this represented "a change of fortune for [a service] deemed commercially dubious by many commentators."<ref name=Times-stats-03June85>
{{
cite newspaper The Times
Line 431 ⟶ 444:
|column=3
}}</ref>
 
Writing in the ''[[The Guardian]]'' just before Christmas 1988, [[Jack Schofield (journalist)|Jack Schofield]] reported that Prestel "had become reclusive" about user numbers, with the Factframe, "[a]fter prompting, ... finally updated this summer ... claim[ing] 90,000 users", while the figure of "only 75,000" was being quoted by the British Telecom manager responsible for the service.<ref name=SchofieldDec88>
{{
cite news
|newspaper=[[The Guardian]]
|date=22 December 1988
|title=Numbers down
|first=Jack
|last=Schofield
|author-link=Jack Schofield (journalist)
|at=p. 27, col 8
|url=https://www.proquest.com/docview/186886612
|id={{ProQuest|186886612}}
}}</ref> In January 1989, drawing on what turned out to be the final Factframe, published at the end of 1988, Schofield wrote that "After ten years, [Prestel] has yet to achieve the number of users it expected to get in its first year", quoting a figure of 95,460 terminals attached.<ref name=SchofieldJan89 /> This was the highest figure claimed during the lifetime of Prestel.<ref name=SettingStage />{{rp|18}}
 
===Decline===
In October 1991, British Telecom closed [[Micronet 800]], stating, in a letter to customers, that "With over 10,000 members, Micronet is easily the largest online service in the UK specialising in microcomputing. However, it is still not large enough to enable us to maintain a cost-effective service and provide the extra facilities requested by our customers."<ref name=MicronetClosure1991>
{{
cite web
|url=https://www.viewdata.org.uk/download.php?cat=15_Prestel&file=micronetrip.pdf
|title=Micronet to close from 31st October 1991
|date=27 September 1991
|first1=Sue
|last1=Gilbody
|type=letter
|publisher=[[Tymnet#BT Tymnet, BT_North America, BTNA|BT Tymnet]]
|archive-url=https://web.archive.org/web/20120506132636/http://www.viewdata.org.uk/download.php?cat=15_Prestel&file=micronetrip.pdf
|archive-date=6 May 2012
}}</ref> Membership had decreased from a peak of around 20,000.<ref name=Rutter />{{rp|145}} ''[[The Guardian]]'' attributed this to the introduction by British Telecom of an off-peak Prestel time-charge in mid-1988, discouraging the use of Micronet's popular "[[Micronet 800#Services provided|Chatline]]" service.<ref name=BrownMicronet1991>
{{
cite news
|newspaper=[[The Guardian]]
|date=31 October 1991
|title=Reaching the end of the line
|first=Mike
|last=Brown
|at=p. 33, col 8
|url=https://www.proquest.com/docview/187285975
|id={{ProQuest|187285975}}
}}</ref> ''[[The Times]]'' agreed, and also pointed to a steep rise in subscription charges, opining that "BT's failure to provide even this committed group with an economic ... service means that Prestel is destined ... for businesses."<ref name=MayMicronet1991>
{{
cite newspaper The Times
|title=Hey Prestel! A disappearing act
|first=Matthew
|last=May
|department=Science and Technology
|date=3 October 1991
|page=30
|issue=64141
|column=1
}}</ref> The closure in April 1991 of Homelink, the [[online banking|home banking]] service launched in 1983 by the [[Nottingham Building Society]],<ref name=HomelinkClosureArticle>
{{
cite journal
|journal=Journal of Retail Banking
|title=Why home banking bombed in Britain
|first=Philip A.
|last=Dover
|volume=15
|issue=4
|date=Winter 1993
|pages=30{{ndash}}38
|id={{Gale|A15141702}}
|issn=0195-2064
}}</ref>{{rp|1}} also contributed to shrinking the number of Prestel subscribers.<ref name=Rutter />{{rp|146}}
 
During 1991, Prestel was closed to residential users.<ref name=Rutter />{{rp|146}} Towards the end of 1993, it was reported that British Telecom was planning to close Prestel altogether: according to the company, of the around 35,000 subscribers at that point, only some 2,500 used the service regularly.<ref name=ClosureLaurance>
{{
cite news
|newspaper=[[The Guardian]]
|date=13 November 1993
|title=British Telecom poised to close its loss-making Prestel service
|first=Ben
|last=Laurance
|at=p. 38, col 5
|url=https://www.proquest.com/docview/187571026
|id={{ProQuest|187571026}}
}}</ref>
 
===Closure===
British Telecom closed Prestel in early 1994, selling it to a [[consortium]]. It was rebranded as "New Prestel", focusing on the provision of financial data to businesses.<ref name=PrestelSaleInd /> In mid-1996, New Prestel transferred to the [[World Wide Web|Web]], becoming the [[Internet service provider]] (ISP) "Prestel On-line"<ref name=PrestelOn-line>
{{
cite news
|newspaper=[[The Independent]]
|title=Steps one, two and three{{snd}}hey Prestel!
|first=Alan
|last=Stewart
|date=28 July 1996
|url=https://www.independent.co.uk/life-style/steps-one-two-and-three-hey-prestel-1331077.html
|access-date=14 December 2024
}}</ref><ref name="PrestelOn-lineArchive">
{{
cite web
|url=http://www.prestel.co.uk/online.htm
|archive-url=https://web.archive.org/web/19970208234324/http://www.prestel.co.uk/online.htm
|archive-date=8 February 1997
|title=Prestel HotZone : Follow the Markets with Prestel On-Line!
|website=Prestel On-line Services
|access-date=14 December 2024
}}</ref>
 
In 1999, the financial data component of Prestel On-line was bought by the company Financial Express to become "Financial Express Prestel".<ref name=FinExpressPrestel>
{{
cite web
|url=https://www.campaignlive.co.uk/article/financial-express-buys-prestel-online/120097
|title=Financial Express buys Prestel Online
|date=20 October 1999
|website=[[Campaign (magazine)|Campaign UK]]
|access-date=14 December 2024
|quote=Online content supplier Financial Express has bought real-time pricing provider Prestel Online from its management team. Following the purchase, FE will change its name to Financial Express Prestel and specialise in supplying data on equities, unit trusts, investment funds and life and pensions funds.
}}</ref> The service component merged with the ISP [[Demon Internet]],<ref name=DemonPrestel>
{{
cite news
|newspaper=M2 PressWire
|title=Prestel: Demon and Prestel alliance creates new Internet force
|date=13 January 1999
|publisher=Normans Media
|id={{Gale|A53563938}}
|quote=Demon Internet and Prestel On-line today announced the alliance of the two Scottish Telecom companies which will create one of the most competitive offerings in the UK Internet Service Provider (ISP) market.
}}</ref> which ran a "Prestel Internet Service". This closed in 2002.<ref name=Rutter />{{rp|146 ft 158}}
 
==Database==
Line 574 ⟶ 706:
{{multiple image
| total_width = 250
| footer = Pocket guide to Prestel for medical practitioners, {{circa|lk=no}} 1984. Their welcome page was 1629.<ref name=MedProgRep>
{{
cite journal
Line 644 ⟶ 776:
|website=[[Centre for Computing History]]
|id=CH56750
}}</ref> [[Micronet 800]], an IP, visualised the relationships between its pages in a [[Tube map|London Tube-style ]] schematic map as part of a guide for users.<ref name=MicronetTubeMap>
{{
cite web
|url=https://archive.org/details/your-guide-to-micronet-1986/mode/2up
|title=Your Guide to Micronet
|page=4
|date=1986
|publisher=Telemap
|location=London
|via=Internet Archive
}}</ref>
 
==Information providers==
There were two types of information provider (IP): main IPs, and sub-IPs.
===Charges===
====Page rental====
A main IP rented pages directly from the [[Post Office Limited|Post Office]] (initially) or [[BT Group|British Telecom]] (later), and owned a three-digit node or "master page" in the database. This required an annual payment in 1982 of £5,500 for a basic package,<ref name=IPcharges>
A main IP rented pages from the [[Post Office Limited|Post Office]] (initially) or [[BT Group|British Telecom]] (later), and controlled a three-digit master-page in the database. In 1982, this cost an annual £5,500 for a basic package,<ref name=IPcharges>
{{
cite web
Line 667 ⟶ 810:
}}</ref>
 
The basic IP package included 100 frames; the ability to enter and amend information, retrieve response frames, and store 10 completed response frames; staff training in editing (a two-day seminar), and a copy of the IP editing manual; and, if required, bulk update facilities and an annual print-out of frames in use. Additional frames were available, in batches of 500, for £500 a year (over £2,600 in 2021),<ref name=MeasuringWorth /> while using "Closed User Groups" (CUGs){{refn|group=lower-alpha|name=CUG|A Closed User Group, or CUG, was a group of Prestel users, set up by an Information Provider, with access to confidential information.<ref name=Handbook1987 />{{rp|18}}}} and the sub-IP facility each cost £250 annually<ref name=IPcharges />{{rp|1}} (over £1,300 in 2021).<ref name=MeasuringWorth />
 
Sub-IPs{{snd}}those with smaller requirements or budget{{snd}}rented pages from a main IP.<ref name=Broadhead>
Line 683 ⟶ 826:
|access-date=7 October 2024
|via=Internet Archive
}}</ref>{{rp|130}} After paying the additional £250 annual fee, aA main IP could rent out individual pages at athe [[market rate]]. Such IPs were known as "umbrella" IPs. Unlike a main IP, subSub-IPs paid a per-minute charge for editing online: in 1982, this was 8p per minute from Monday to Friday between 8 am and 6 pm, and 8p per 4four-minute block at all other times<ref name=IPcharges />{{rp|1}} (equivalent to around 35p as at end 2014).<ref name=MeasuringWorth /> Sub-IPs were restricted to pages underhad a 4four-digit (or more) digit nodemaster-page within a main IP's area. Generally speaking, andthey could only edit existing pages:, theyand were not able to create or delete pages themselvesthem.
 
====Prestel Gateway====
The cost to an IP of connecting an external computer to the Prestel system varied according to the number of simultaneous users required, the distance between Prestel and the IP's computer, and whether the connection was made using a private line or via the [[Packet Switch Stream|PSS]] [[packet switching|packet-switched]] network. There were also time and data-volume charges.<ref name=GatewayCharges>
{{
cite document
|title=Prestel Travel Tariff Guide
|date=November 1985
|type=brochure
|publisher=Prestel Travel
|location=London
}}</ref>{{rp|3}}
 
In 1985, British Telecom estimated that for an IP using a typical [[minicomputer]] (such as the [[PDP-11]]) located 100 km from London and handling up to 10 users simultaneously at peak times, the one-off software set-up cost would be at least £16,000, communication costs would range from £4,280 to £5,550 a year (depending on the type of connection), and Prestel usage would cost £8,600 a year.<ref name=GatewayCharges />{{rp|4}}
 
===Relationships===
Several typical relationships developed between umbrella IPs and their sub-IP clients. A sub-IP could be:<ref name=Williams-IPs />{{rp|99}}
* The sub-IP was anAn independent supplier of information, with exclusive or partial editorial control and full or partial editing rights.
* An organisation mademaking information available to an IP, sometimes on a [[Royalty payment|royalty]] basis.
* An organisation advertisedadvertising on an IP's pages.
* An individual authoredauthoring articles or [[Column (periodical)|columns]] for an IP, usually on a royalty basis.
 
In addition, the IP [[Micronet 800]] used the sub-IP facility to offer the "Gallery" service, where a group, club, or individual could rent one or a number of frames cheaply, and for short periods if required.<ref name=Micronet800Brochure1990>
Line 794 ⟶ 950:
|publisher=ICV Information Systems
}}</ref>
 
*''British Telecom Travel Service'' provided travel agents with information from tour operators, airlines, and other transport operators, and enabled online reservations. The service for other users included flight arrivals and departures, car rental, and exchange rates.
*''British Telecom Travel Service'' provided travel agents with information from tour operators, airlines, and other transport operators, and enabled online reservations. Services for other users included flight arrivals and departures, car rental, and exchange rates.
*''Prestel Farmlink'' packaged information for farmers from the [[Ministry of Agriculture, Fisheries and Food (United Kingdom)|Ministry of Agriculture, Fisheries and Food]], the [[Meat and Livestock Commission]], the [[Met Office|Meteorological Office]], and others. A link to Prestel CitiService provided farm commodity prices, and farmers could calculate, online, weekly wages and the formulation of feedstuffs.
 
*''Prestel Farmlink'' packaged information for farmers from the [[Ministry of Agriculture, Fisheries and Food (United Kingdom)|Ministry of Agriculture, Fisheries and Food]], the [[Meat and Livestock Commission]], the [[Met Office|Meteorological Office]], and others. A link to Prestel CitiService provided farm commodity prices, and farmers could calculate, online, weekly wages and the formulation of feedstuffs.<ref name=FarmlinkCMA1985>
{{
cite book
|title=Centre of Management in Agriculture Yearbook 1984/1985
|date=June 1985
|url=https://www.iagrm.com/content/large/journals/cma/1984-85/centre-of-management-in-agriculture-yearbook-1984-85-lowres.pdf#page=67
|chapter=Prestel Farmlink
|first=Thea
|last=James
|pages=65,&nbsp;67
|via=Institute of Agricultural Management
|access-date=30 November 2024
}}</ref>
 
*Banking: the [[Nottingham Building Society]] offered Homelink, and the [[Bank of Scotland]] HOBS, the Home & Office Banking Service.<ref name=BoSHomeBankAd>
{{
Line 805 ⟶ 976:
|issue=62070
|url=https://www.thetimes.com/tto/archive/page/1983-04-26/22.html
}}</ref> Subscribers were provided with free or subsidised Prestel terminals.
*''Prestel Microcomputing'' offered downloadable software ([[telesoftware]]), noticeboards, newsletters, and reviews. It incorporated [[Micronet 800]] from [[Ascential|EMAP]], Viewfax 258, and Clubspot 810.<ref name=MicroLaunchLetter>
{{
cite document
|title=PRESTELPrestel MICROCOMPUTINGMicrocomputing will add a new dimension to your home computing
|date=May 1984
|type=letter
Line 815 ⟶ 987:
|publisher=[[BT Group|British Telecom]]
}}</ref>
 
*''Prestel Education'' targeted schools and colleges, and provided course and careers advice, educational software, and help with using computers.<ref name=EducationTimes>
{{
Line 826 ⟶ 999:
|url=https://www.thetimes.com/tto/archive/page/1985-01-29/3.html
}}</ref>
 
*''British Telecom Insurance Services'' provided financial information to [[Insurance broker#In the United Kingdom|insurance intermediaries]] and enabled them to get online quotes from major insurance companies.<ref name=BTInsuranceGdn>
{{
Line 837 ⟶ 1,011:
|url=https://www.proquest.com/docview/186749481/
}}</ref>
 
*''Prestel Teleshopping'' was a specialised [[e-commerce]] service for the residential market, and involved [[Littlewoods]] and [[Kays Catalogues]], among others.
*''Prestel Teleshopping'' was a specialised [[e-commerce]] service for the residential market, and involved [[Littlewoods]], [[Grattan plc|Grattan]], and [[Kays Catalogues]], among others.<ref name=TeleshoppingBTJ>
{{
cite journal
|journal=British Telecom Journal
|title=Armchair shopping delivers the goods
|first=Jane
|last=Young
|volume=8
|issue=2
|date=Summer 1987
|pages=76{{ndash}}77
|url=https://archive.org/details/btj-198707/page/n91/mode/2up
|access-date=30 November 2024
|issn=0260-1532
|oclc=8560549
|via=Internet Archive
}} Shows two "Kays Catalogues Teleshop" frames.</ref>
 
*''Prestel for Medical Practitioners'' packaged material from bodies such as the [[Royal College of General Practitioners]], the [[British Medical Association]], and the [[Department of Health and Social Security]] with drug data from pharmaceutical companies, information on [[Locum#United Kingdom healthcare|locum]] vacancies, conference and training diaries, and research news.<ref name=MedProgRep />
 
==Messaging==
 
===Response frames===
A "response frame" enabled a user to send a message to an IP using a special preformatted page, for example to order goods or services.<ref name=Broadhead />{{rp|133}} The user's name, address, and phone number were automatically addedor to the frame by means of embedded codes that triggered the extraction of thistransmit data from their Prestel account.<ref name=MedDataCollect>
{{
cite journal
|journal=[[The BMJ#Editions|British Medical Journal (Clinical Research Edition)]]
|title=Use of a viewdata system to collect data from a multicentre clinical trial in anaesthesia
|first1=H. A.
|last1=Waldron
|first2=R. F.
|last2=Cookson
|volume=289
|issue=6451
|pages=1059{{ndash}}1061
|date=20 October 1984
|issn=0267-0623
|url=https://www.bmj.com/content/bmj/289/6451/1059.full.pdf
|access-date=9 December 2024
|doi=10.1136/bmj.289.6451.1059
|doi-access=free
}}
</ref> The user's name and other information needed (such as their address) were automatically added to the frame from their Prestel account details.
 
Initially, response frames had to be collected by an IP from each IRC in turn; later, they were ingathered at the UDC, where the IP concerned could retrieve them. Eventually, with the introduction of Mailbox, response frames could be retrieved from any IRC. {{section link|#Network}}
Line 913 ⟶ 1,125:
 
===Mailbox upgrade===
A new messaging system was introduced in July 1989. This enabled messages up to five frames long, storing messages before sending, sending to multiple recipients (either individually or via a mailing list), message forwarding, and acknowledgment of receipt.<ref name=MboxUpgradeMicronetArticle>
{{
cite magazine
|magazine=Log On{{snd}}The magazine for Micronet members
|title=Mailbox Mark Two: so what's in it for you?
|issue=9
|pages=10{{ndash}}11
|date=Autumn 1989
}} An interview with Chris Ramsey, the Mailbox manager.</ref>
 
Sending a basic message without using any of these new facilities remained free: all the new options were charged at 1p per use per recipient. For the first time, sending [[E-mail spam|spam]] was permitted at a cost of 20p per message per recipient. In addition, the stored message facility was replaced by a summary page listing all the messages, both new and old, that were waiting: the user could then pick which message to view, rather than needing to read through them in chronological order.<ref name=MboxUpgradeCharges>
Line 962 ⟶ 1,182:
 
==Infrastructure==
===Terminals===
During the development phase of Prestel, British Telecom's research department produced a Prestel terminal specification. This formed the basis of design and [[type approval|type-approval]] discussions with, initially, manufacturers of TVs, and later with suppliers of other forms of terminal.<ref name=PrestelTermSpec1982>
{{
cite journal
|journal=British Telecommunications Engineering Journal
|title=Prestel terminals
|first=G. D.
|last=Hudson
|volume=1
|issue=1
|pages=35{{ndash}}41
|date=April 1982
|access-date=3 December 2024
|url=https://archive.org/details/bte-198204/page/n38/mode/1up
|issn=0262-401X
|via=Internet Archive
}} Pictured in the article are a [[Philips]] residential terminal equipped for Prestel, [[teletext]] and normal television reception, a [[Sony]] business terminal with message keyboard, a Zycor Prestel adaptor with a normal domestic television, and a Metrotech information provider editing terminal.</ref>
 
Several types of Prestel terminal were produced:<ref name=ButlerCox1985 />{{rp|75{{ndash}}77}}
* integrated residential terminals, typically based on television sets;
* integrated business terminals;
* adaptors for television sets;
* adaptors for microcomputers, with associated or standalone editing software;
* editing terminals.
===Network===
====Configuration and growth====
Line 1,069 ⟶ 1,313:
====Mailbox computer====
{{see also|#Mailbox}}
Mailbox, the Prestel messaging service, was launched on Enterprise computer, and allowed messaging only between users accessing that machine. By 1984, Mailbox had been rolled out nationwide using a dedicated computer in London known as Pandora.<ref name=MboxUpgradeMicronetArticle />{{citation neededrp|date=October11 col 20241}}
 
===Hardware===
Line 1,160 ⟶ 1,404:
 
==International sales==
The Prestel systemsoftware and [[Procedural knowledge|knowhow]] was sold to several countries, including Austria,<ref name=SaleAustria>
{{
cite news
Line 1,194 ⟶ 1,438:
|quote=The West German Post Office will be supplied with a duplicate of the Viewdata computer programmes {{sic}} and expertise, and a trial system will be set up with the guidance of the British Post Office.
}}
</ref> the then-British colony of [[British Hong Kong|Hong Kong]],<ref name=ButlerCox1982 />{{rp|7, 8}} Hungary, Italy, Malaysia,<ref name=SaleMalaysia>
{{
cite newspaper The Times
Line 1,218 ⟶ 1,462:
|oclc=8735559
}}</ref> and former [[Yugoslavia]].{{citation needed|date=October 2024}}
 
[[Telstra|Telecom Australia]] re-branded their system Viatel, with the centre of operations in [[Windsor, Victoria|Windsor]], [[Melbourne]], [[Australia]]. During the [[Black Monday (1987)|Black Monday]] stock market crash the system's stock trading system was highly used. The system in Italy run by [[Telecom Italia|SIP]] was heavily used during the [[1990 FIFA World Cup]] for reporting the match progress and scores. The Singapore system provided a much higher receive bandwidth than was available over dial-up modems at the time by broadcasting the return frames using the [[Teletext]] technique of embedding them in broadcast television signals. Four [[VHF]] TV channels were dedicated to this with all the [[scan line]]s used for Teletext encoding, which enabled the system to provide a feature called ''Picture Prestel'' to convey higher resolution images. The Yugoslav system was based in [[Zagreb]], with additional IRCs located in [[Rijeka]], [[Ljubljana]], and [[Split, Croatia|Split]].{{citation needed|date=October 2024}}
 
The American [[Viewtron]] videotex service was modelled after Prestel.{{citation needed|date=October 2024}}
 
==See also==
Line 1,234 ⟶ 1,474:
*{{annotated link|Telidon}}
*{{annotated link|videotex}}
*{{annotated link|Viewtron}}
 
==Notes==
Retrieved from "https://en.wikipedia.org/wiki/Prestel"