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History Of Operating Systems
Computer operating systems (OSes) provide a set of functions needed and used by most application programs on a computer, and the links needed to control and synchronize computer hardware. On the first computers, with no operating system, every program needed the full hardware specification to run correctly and perform standard tasks, and its own drivers for peripheral devices like printers and punched paper card readers. The growing complexity of hardware and application programs eventually made operating systems a necessity for everyday use. Background Early computers lacked any form of operating system. Instead, the user, also called the operator, had sole use of the machine for a scheduled period of time. The operator would arrive at the computer with program and data which needed to be loaded into the machine before the program could be run. Loading of program and data was accomplished in various ways including toggle switches, punched paper cards and magnetic or paper ta ...
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Operating System
An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for efficient use of the system and may also include accounting software for cost allocation of Scheduling (computing), processor time, mass storage, peripherals, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computerfrom cellular phones and video game consoles to web servers and supercomputers. , Android (operating system), Android is the most popular operating system with a 46% market share, followed ...
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Kernel (operating System)
A kernel is a computer program at the core of a computer's operating system that always has complete control over everything in the system. The kernel is also responsible for preventing and mitigating conflicts between different processes. It is the portion of the operating system code that is always resident in memory and facilitates interactions between hardware and software components. A full kernel controls all hardware resources (e.g. I/O, memory, cryptography) via device drivers, arbitrates conflicts between processes concerning such resources, and optimizes the use of common resources, such as CPU, cache, file systems, and network sockets. On most systems, the kernel is one of the first programs loaded on startup (after the bootloader). It handles the rest of startup as well as memory, peripherals, and input/output (I/O) requests from software, translating them into data-processing instructions for the central processing unit. The critical code of the kernel is usua ...
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The Mythical Man-Month
''The Mythical Man-Month: Essays on Software Engineering'' is a book on software engineering and project management by Fred Brooks first published in 1975, with subsequent editions in 1982 and 1995. Its central theme is that adding manpower to a software project that is behind schedule delays it even longer. This idea is known as Brooks's law, and is presented along with the second-system effect and advocacy of Software prototyping, prototyping. Brooks's observations are based on his experiences at IBM while managing the development of OS/360. He had added more programmers to a project falling behind schedule, a decision that he would later conclude had, counter-intuitively, delayed the project even further. He also made the mistake of asserting that one project—involved in writing an ALGOL compiler—would require six months, regardless of the number of workers involved (it required longer). The tendency for managers to repeat such errors in project development led Brooks to qui ...
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Fred Brooks
Frederick Phillips Brooks Jr. (April 19, 1931 – November 17, 2022) was an American computer architect, software engineer, and computer scientist, best known for managing development of IBM's System/360 family of mainframe computers and the OS/360 software support package, then later writing candidly about those experiences in his seminal book '' The Mythical Man-Month''. In 1976, Brooks was elected to the National Academy of Engineering for "contributions to computer system design and the development of academic programs in computer sciences". Brooks received many awards, including the National Medal of Technology in 1985 and the Turing Award in 1999. Education Born on April 19, 1931, in Durham, North Carolina, he attended Duke University, graduating in 1953 with a Bachelor of Science degree in physics, and he received a Ph.D. in applied mathematics (computer science) from Harvard University in 1956, supervised by Howard Aiken. Brooks served as the graduate teaching a ...
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OS/360 And Successors
OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB and Input/Output Control System (IOCS) packages for the IBM 7090/7094 and even more so by the PR155 Operating System for the IBM 1410/ 7010 processors. It was one of the earliestJust a few years after Atlas Supervisor, Burroughs MCP and GECOS operating systems to require the computer hardware to include at least one direct access storage device. Although OS/360 itself was discontinued, successor operating systems, including the virtual storage MVS and the 64-bit z/OS, are still run and maintain application-level compatibility with OS/360. Overview IBM announced three different levels of OS/360, generated from the same tapes and sharing most of their code. IBM eventually renamed these options and made some significant design changes: ...
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IBM System/360
The IBM System/360 (S/360) is a family of mainframe computer systems announced by IBM on April 7, 1964, and delivered between 1965 and 1978. System/360 was the first family of computers designed to cover both commercial and scientific applications and a complete range of applications from small to large. The design distinguished between architecture and implementation, allowing IBM to release a suite of compatible designs at different prices. All but the only partially compatible Model 44 and the most expensive systems use microcode to implement the instruction set, featuring 8-bit byte addressing and fixed-point binary, fixed-point decimal and hexadecimal floating-point calculations. The System/360 family introduced IBM's Solid Logic Technology (SLT), which packed more transistors onto a circuit card, allowing more powerful but smaller computers. System/360's chief architect was Gene Amdahl, and the project was managed by Fred Brooks, responsible to Chairman Thomas J. Wat ...
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Mainframe Computer
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, server (computing), 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. The term ''mainframe'' was derived from the large cabinet, called a ''main frame'', that housed the central processing unit and main computer memory, memory of early computers. Later, the term ''mainframe'' was used to distinguish high-end commercial computers from less powerful machines. Design Modern mainfr ...
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Computer History Museum
The Computer History Museum (CHM) is a computer museum in Mountain View, California. The museum presents stories and artifacts of Silicon Valley and the Information Age, and explores the Digital Revolution, computing revolution and its impact on society. History The museum's origins date to 1968 when Gordon Bell began a quest for a historical collection and, at that same time, others were looking to preserve the Whirlwind (computer), Whirlwind computer. The resulting ''Museum Project'' had its first exhibit in 1975, located in a converted coat closet in a Digital Equipment Corporation, DEC lobby. In 1978, the museum, now ''The Digital Computer Museum'' (TDCM), moved to a larger DEC lobby in Marlborough, Massachusetts and opened to the public in September 1979. Maurice Wilkes presented the first lecture at TDCM in 1979 – the presentation of such lectures has continued to the present time. TDCM incorporated as ''The Computer Museum, Boston, The Computer Museum'' (TCM) in 1982. ...
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IBM 704
The IBM 704 is the model name of a large digital computer, digital mainframe computer introduced by IBM in 1954. Designed by John Backus and Gene Amdahl, it was the first mass-produced computer with hardware for floating-point arithmetic. The IBM 704 ''Manual of operation'' states: The type 704 Electronic Data-Processing Machine is a large-scale, high-speed electronic calculator controlled by an internally stored program of the single address type. The 704 at that time was thus regarded as "pretty much the only computer that could handle complex math". The 704 was a significant improvement over the earlier IBM 701 in terms of architecture and implementation. Like the 701, the 704 used vacuum-tube logic circuitry, but increased the instruction size from 18-bit computing, 18 bits to 36-bit computing, 36 bits, the same as the memory's word size. Changes from the 701 include the use of magnetic-core memory instead of Williams tubes, floating-point arithmetic instructions, 15 ...
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RAND Corporation
The RAND Corporation, doing business as RAND, is an American nonprofit global policy think tank, research institute, and public sector consulting firm. RAND engages in research and development (R&D) in several fields and industries. Since the 1950s, RAND research has helped inform United States policy decisions on a wide variety of issues, including the Cold War space race, the U.S. involvement in the Vietnam War, the U.S.–Soviet nuclear arms confrontation, the creation of the Great Society social welfare programs, and national health care. RAND originated as "Project RAND" (from the phrase "research and development") in the post-war period immediately after World War II. The U.S. Army Air Forces established Project RAND with the objective of investigating long-range planning of future weapons. Douglas Aircraft Company was granted a contract to research intercontinental warfare. Project RAND later evolved into RAND, and expanded its research into civilian fields suc ...
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General Motors
General Motors Company (GM) is an American Multinational corporation, multinational Automotive industry, automotive manufacturing company headquartered in Detroit, Michigan, United States. The company is most known for owning and manufacturing four automobile brands: Chevrolet, Buick, GMC (marque), GMC, and Cadillac, each a separate division of GM. By total sales, it has continuously been the largest automaker in the United States, and was the List of manufacturers by motor vehicle production, largest in the world for 77 years before losing the top spot to Toyota in 2008. General Motors operates manufacturing plants in eight countries. In addition to its four core brands, GM also holds interests in Chinese brands Baojun and SAIC-GM-Wuling, Wuling via SAIC-GM-Wuling, SAIC-GM-Wuling Automobile. GM further owns GM Defense, a namesake defense vehicles division which produces military vehicles for the United States government and military, the vehicle safety, security, and information ...
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GM-NAA I/O
The GM-NAA I/O input/output system of General Motors and North American Aviation was the first operating system for the IBM 704 computer. It was created in 1956 by Robert L. Patrick of General Motors Research and Owen Mock of North American Aviation. It was based on a system monitor created in 1955 by programmers of General Motors for its IBM 701. Patrick made Gantt charts which were already used in those days by GM for automotive production line design on how to make parallel processes fit together. The main function of GM-NAA I/O was to automatically execute a new program once the one that was being executed had finished (batch processing). It was formed of shared routines to the programs that provided common access to the input/output devices. Some version of the system was used in about forty 704 installations. See also * SHARE Operating System, an operating system based on GM-NAA I/O. * Multiple Console Time Sharing System *Timeline of operating systems *Resident monito ...
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