This volume discusses British firms that were engaged in electronics and defence-designed and manufactured general-purpose computer systems in support of their mission focus. The other major vendors saw opportunities for computer systems within their respective domains and proceeded to fill those gaps. For each vendor, we examine their system architecture, operating systems (where data is available), programming languages, and applications. Unique features are pointed out that characterize each vendor. Most notable was Ferranti, which began with a collaboration with the University of Manchester, UK, then branched out to pursue independent designs for industrial control. After Marconi Electronics absorbed several other vendors, it based its machines on University of Manchester systems. The Engineering Mechanics Industrial Development and Engineering Corporation (EMIDEC) focused on business data processing where its EMIDEC 1100 became the Internation Computers and Tabulators ICT 1301. Standard Telephone and Cables (STC) developed the ZEBRA for use in scientific and mathematical computing and pioneered the use of "plug-in" modules. These firms continued innovation in computing in different areas, but eventually disappeared through mergers as the computer industry consolidated through government intervention, including ICT, to form International Computers, Limited (ICL). ICL was acquired by Fujitsu Corporation in the 1990s, in whose systems many of these ideas survive today. In hindsight, the evolution of computing hardware design and development and manufacturing processes was a key contribution of these companies.
