[1] Btx originally required special hardware (it was based on GEC 4000 series computers) which had to be bought or rented from the British General Post Office.

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 profile.

[5] The system was launched nationwide in 1983, at the press of a button by the Federal Post Minister at Berlin's IFA[5] The service could only be used with a modem produced by the Bundespost and user uptake was low.

[5] In 1995, an enhanced backward-compatible standard called Kernel for Intelligent Communication Terminals (KIT) was announced, but this never really gained acceptance.

Btx permits the transmission of graphical pages with a resolution of 480 by 250 pixels, where 32 out of a palette of 4096 colors could be shown at the same time.