A disk operating system (DOS) is a computer operating system that resides on and can use a disk storage device, such as a floppy disk, hard disk drive, or optical disc. A disk operating system provides a file system for organizing, reading, and writing files on the storage disk, and a means for loading and running programs stored on that disk. Strictly, this definition does not include any other functionality, so it does not apply to more complex OSes, such as Microsoft Windows, and is more appropriately used only for older generations of operating systems.
A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterprise resource planning, and large-scale transaction processing. A mainframe computer is large but not as large as a supercomputer and has more processing power than some other classes of computers, such as minicomputers, servers, workstations, and personal computers. Most large-scale computer-system architectures were established in the 1960s, but they continue to evolve. Mainframe computers are often used as servers.
A minicomputer, or colloquially mini, is a type of smaller general-purpose computer developed in the mid-1960s and sold at a much lower price than mainframe and mid-size computers from IBM and its direct competitors. In a 1970 survey, The New York Times suggested a consensus definition of a minicomputer as a machine costing less than US$25,000, with an input-output device such as a teleprinter and at least four thousand words of memory, that is capable of running programs in a higher level language, such as Fortran or BASIC.
The Business Operating System, or BOS, was initially developed as an early cross-platform operating system, originally for Intel 8080 and Motorola 6800 microprocessors and then for actual businesses and business models. The technology was used in Zilog Z80-based computers and later for most microcomputers of the 1980s. The system was developed by CAP Ltd, a British company that later became one of the world's largest Information Technology consulting firms. BOS and BOS applications were designed to be platform-independent.
Logica plc was a multinational IT and management consultancy company headquartered in London and later Reading, United Kingdom.
International Computers Limited (ICL) was a British computer hardware, computer software and computer services company that operated from 1968 until 2002. It was formed through a merger of International Computers and Tabulators (ICT), English Electric Computers (EEC) and Elliott Automation in 1968. The company's most successful product line was the ICL 2900 Series range of mainframe computers.
The Integrated Electronic Control Centre (IECC) was developed in the late 1980s by the British Rail Research Division for UK-based railway signalling centres, although variations exist around the world. It is the most widely deployed VDU based signalling control system in the UK, with over 50 workstations in control centres that manage many of the most complex and busy areas of the network.
Sir John Alexander Raymond Chisholm is a British engineer who was chairman of the Medical Research Council and QinetiQ.
CAP Scientific Ltd was a British defence software company, and was part of CAP Group plc. In 1988, CAP Group merged with the French firm Sema-Metra SA in 1988 as Sema Group plc. In 1991 Sema Group put most of its defence operations into joint venture with British Aerospace called BAeSEMA, which British Aerospace bought out in 1998. Parts of the former CAP Scientific are now BAE Systems (Insyte).
The Socialist Federal Republic of Yugoslavia (SFRY) was a socialist country that existed in the second half of the 20th century. Being socialist meant that strict technology import rules and regulations shaped the development of computer history in the country, unlike in the Western world. However, since it was a non-aligned country, it had no ties to the Soviet Bloc either. One of the major ideas contributing to the development of any technology in SFRY was the apparent need to be independent of foreign suppliers for spare parts, fueling domestic computer development.
SMCS, the Submarine Command System, was first created for the Royal Navy of the United Kingdom's Vanguard-class submarines as a tactical information system and a torpedo weapon control system. Versions have now also been installed on all active Royal Navy submarine classes.
Sema Group plc was an Anglo-French IT services company. It was listed on the London Stock Exchange and was a constituent of the FTSE 100 Index. It was acquired by Schlumberger in 2001.
Micro Focus International plc was a British multinational software and information technology business based in Newbury, Berkshire, England. The firm provided software and consultancy. The company was listed on the London Stock Exchange and the New York Stock Exchange until it was acquired by the Canadian software firm OpenText in January 2023.
Service in Informatics and Analysis was one of the pioneering time-sharing service bureau companies in the late 1960s, later known as SIA Computer Services. Its head office was located at Lower Belgrave Street, close to Victoria Station in London, and the company had branch offices in Edinburgh, Manchester, the West End, Paris and in Hong Kong. SIA offered terminal services via the Post Office telephone network at speeds of 10, 15, 30, 60 and 120 characters per second for Teletype-style terminals and of 1200 baud, 2400 baud and 4800 baud for Remote Job Entry terminals. Later with the release of the IBM PC, systems were developed to emulate the Remote Batch and interactive terminals. Clients could also visit the head or branch offices to submit their jobs personally or have them accepted and supervised by the production department.
Hitachi Data Systems (HDS) was a provider of modular mid-range and high-end computer data storage systems, software and services. Its operations are now a part of Hitachi Vantara.
The following outline is provided as an overview of and topical guide to computing:
SCISYS PLC was a pan-European computer software and services company based in the United Kingdom and Germany. The company was formed in 1980 as Science Systems and was acquired by CGI in 2019.
Computer Corporation of America (CCA) was a computer software and database systems company founded in 1965. It was best known for its Model 204 (M204) database system for IBM and compatible mainframes.
Candle Corporation was an American software company active from 1976 to 2004. The company spent the first two decades developing system monitoring applications for a variety of IBM mainframes and their corresponding software, their first being OMEGAMON which saw quick widespread adoption in commercial enterprises. In the mid-1990s, the company made pivots toward non-mainframe monitoring software and middleware. IBM acquired the company for between $350 million and $600 million in 2004.
