Operating system is a system software. Operating system manages computer hardware and software and resources. An operating system is a software that allows to run application on computer. Operating system provides services to facilitate the efficient execution and management. Without a operating system our computer is just a box. We can use our computer without operating system. But our computer may stop working without a operating system. Because operating system is software that allows to run other applications on our computer. We will have difficulty to use our computer. Because without a operating system there are no system software that can allow other software to run. So we must need a operating system. Without a operating system we can run only one software.
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The first operating system was invented in the 50's. The first operating system used for real work was GM-NAA I/O, produced in 1956 by General Motors. Microsoft's first operating system, MDOS/MIDAS, was designed along many of the PDP-11 features, but for microprocessor based systems. MS-DOS, or PC DOS when supplied by IBM, was based originally on CP/M-80.
