Bildschirmtext ( German "screen text", abbrev. Btx or BTX) was an

online In computer technology and telecommunications, online indicates a state of connectivity, and offline indicates a disconnected state. In modern terminology, this usually refers to an Internet connection, but (especially when expressed as "on lin ...

videotex Videotex (or interactive videotex) was one of the earliest implementations of an end-user information system. From the late 1970s to early 2010s, it was used to deliver information (usually pages of text) to a user in computer-like format, typi ...

system launched in

West Germany West Germany was the common English name for the Federal Republic of Germany (FRG) from its formation on 23 May 1949 until German reunification, its reunification with East Germany on 3 October 1990. It is sometimes known as the Bonn Republi ...

in 1983 by the Deutsche Bundespost, the (West) German

postal service The mail or post is a system for physically transporting postcards, letters, and parcels. A postal service can be private or public, though many governments place restrictions on private systems. Since the mid-19th century, national postal sy ...

. Btx originally required special hardware (it was based on

GEC 4000 series The GEC 4000 was a series of 16-bit, 16/32-bit minicomputers produced by GEC Computers, GEC Computers Ltd in the United Kingdom during the 1970s, 1980s and early 1990s. History GEC Computers was formed in 1968 as a business unit of the Gen ...

computers) which had to be bought or rented from the British

General Post Office The General Post Office (GPO) was the state postal system and telecommunications carrier of the United Kingdom until 1969. Established in England in the 17th century, the GPO was a state monopoly covering the dispatch of items from a specific ...

. The data was transmitted through the telephone network using V.23

modem The Democratic Movement (, ; MoDem ) is a centre to centre-right political party in France, whose main ideological trends are liberalism and Christian democracy, and that is characterised by a strong pro-Europeanist stance. MoDem was establis ...

s and the content was displayed on a

television Television (TV) is a telecommunication medium for transmitting moving images and sound. Additionally, the term can refer to a physical television set rather than the medium of transmission. Television is a mass medium for advertising, ...

set.

History

Originally conceived to follow the UK Prestel specifications, and developed on contract by a small UK company called Systems Designers Ltd (originally merged into EDS and now part of HP) for

IBM International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

Germany. Btx added a number of additional features before launch, including some inspired by the French Minitel service, to create a new display standard of its own, which in 1981 was designated the

CEPT1 CEPT Recommendation T/CD 06-01 was a standard set in 1981 by the European Conference of Postal and Telecommunications Administrations (CEPT) for the display of Videotex; specifically, for the ''Videotex Presentation Layer Data Syntax''. It was revi ...

profile. The system was presented at the IFA in

Berlin Berlin ( ; ) is the Capital of Germany, capital and largest city of Germany, by both area and List of cities in Germany by population, population. With 3.7 million inhabitants, it has the List of cities in the European Union by population withi ...

, with a trial system installed in

Düsseldorf Düsseldorf is the capital city of North Rhine-Westphalia, the most populous state of Germany. It is the second-largest city in the state after Cologne and the List of cities in Germany with more than 100,000 inhabitants, seventh-largest city ...

and Berlin in 1980. In 1981, the system was expanded to rest of Germany, with the necessary network being developed by

. The system was launched nationwide in 1983, at the press of a button by the Federal Post Minister at Berlin's IFA The service could only be used with a modem produced by the Bundespost and user uptake was low. The "MultiTel" devices could operate without a TV and allowed simultaneous telephone operation. By 1986, there were also adaptor devices for home computers like the

Commodore 64 The Commodore 64, also known as the C64, is an 8-bit computing, 8-bit home computer introduced in January 1982 by Commodore International (first shown at the Consumer Electronics Show, January 7–10, 1982, in Las Vegas). It has been listed in ...

(ex: Siemens Decoder Module II). By the 1990s, the system was renamed "Datex-J" and focused on the home users. In 1995, an enhanced backward-compatible standard called Kernel for Intelligent Communication Terminals (KIT) was announced, but this never really gained acceptance. Btx formed the basis of T-Online, Deutsche Telekom's online service, which maintained a Btx interface in its access software after the T-Online brand was introduced in 1995. After

German reunification German reunification () was the process of re-establishing Germany as a single sovereign state, which began on 9 November 1989 and culminated on 3 October 1990 with the dissolution of the East Germany, German Democratic Republic and the int ...

, Btx was available throughout

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

. Btx was also available in

Austria Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ...

and

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

, where it was called ''Videotex'' (VTX). The last Btx access was switched off at the end of 2001 by

Deutsche Telekom Deutsche Telekom AG (, ; often just Telekom, DTAG or DT; stylised as ·T·) is a partially state-owned German telecommunications company headquartered in Bonn and the largest telecommunications provider in Europe by revenue. It was formed in 199 ...

; it had been made obsolete by the

Internet The Internet (or internet) is the Global network, global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a internetworking, network of networks ...

Operation

Btx permits the transmission of graphical pages with a resolution of 480 by 250

pixel In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a Raster graphics, raster image, or the smallest addressable element in a dot matrix display device. In most digital display devices, p ...

s, where 32 out of a palette of 4096 colors could be shown at the same time. Each page could display 40×24 semigraphic text characters. This corresponds to the technical possibilities of the early 1980s. Btx always transferred whole screen pages; the receiver paid per received page. The content provider was free to set the price, and could require either a fee per page (0.01 DM to 9.99 DM), or a time-dependent fee (0.01 DM to 1.30 DM per minute). Data was transferred unauthenticated and in plaintext, leading to the BTX hack by Wau Holland in 1984.

In Media

Bildschirmtext is referenced in the German language version of the song " Computerliebe" by Kraftwerk. The song's lyrics, "Ich wähl die Nummer, ich wähl die Nummer / Rufe Bildschirmtext, rufe Bildschirmtext" ("I call this number, I call this number / Call Bildschirmtext, call Bildschirmtext"), reference the service as it was in 1981.

References

External links

Screen Shots from Btx terminal displaying its description and history

Some example pages

''

Der Spiegel (, , stylized in all caps) is a German weekly news magazine published in Hamburg. With a weekly circulation of about 724,000 copies in 2022, it is one of the largest such publications in Europe. It was founded in 1947 by John Seymour Chaloner ...

'', 14 March 1983. Article on the launch of the system. {{Videotex Computer-related introductions in 1983 History of telecommunications in Germany Videotex Deutsche Telekom