Operating system

An operating system (OS) manages computer resources and provides programmers with an interface used to access those resources. An operating system processes system data and user input, and responds by allocating and managing tasks and internal system resources as a service to users and programs of the system. An operating system performs basic tasks such as controlling and allocating memory, prioritizing system requests, controlling input and output devices, facilitating computer networking, and managing files. Common contemporary desktop operating systems are Microsoft Windows, macOS, Linux, Solaris and FreeBSD. Windows, macOS, and Linux all have server and personal variants. With the exception of Microsoft Windows, the designs of each of them were inspired by or directly inherited from the Unix operating system, which was developed at Bell Labs beginning in the late 1960s and spawned the development of numerous free and proprietary operating systems. Microsoft Windows[edit] Main article: Microsoft Windows Microsoft Windows is the collective brand name of several operating systems made by Microsoft which, as of 2015, are installed on PCs built by HP, Dell and Lenovo, the three remaining high volume manufacturers.[52] Microsoft first introduced an operating environment named Windows in November 1985,[53] as an add-on to MS-DOS and in response to the growing interest in graphical user interfaces (GUIs)[54][55] generated by Apple's 1984 introduction of the Macintosh.[56] As of January 2017, the most recent client and server version of Windows are Windows 10 and Windows Server 2016. macOS[edit] Main article: macOS macOS (formerly OS X) is a line of operating systems developed, marketed and sold by Apple Inc. macOS is the successor to the original Mac OS, which had been Apple's primary operating system since 1984. macOS is a Unix-based graphical operating system, and Snow Leopard, Leopard, Lion, Mountain Lion, Mavericks, Yosemite and El Capitan are its version codenames. The most recent version of macOS is codenamed macOS Sierra. On iPhone, iPad and iPod, versions of iOS (which is an OS X derivative) are available from iOS 1.0 to the recent iOS 10. The iOS devices, however, are not considered PCs. Linux[edit] Main article: Linux A Linux distribution running KDE Plasma Workspaces 4 Linux is a family of Unix-like computer operating systems. Linux is one of the most prominent examples of free software and open source development: typically all underlying source code can be freely modified, used, and redistributed by anyone.[57] The name "Linux" refers to the Linux kernel, started in 1991 by Linus Torvalds. The system's utilities and libraries usually come from the GNU operating system, announced in 1983 by Richard Stallman. The GNU contribution is the basis for the alternative name GNU/Linux.[58] Known for its use in servers, with the LAMP application stack as one of prominent examples, Linux is supported by corporations such as Dell, Hewlett-Packard, IBM, Novell, Oracle Corporation, Red Hat, Canonical Ltd. and Sun Microsystems. It is used as an operating system for a wide variety of computer hardware, including desktop computers, netbooks, supercomputers,[59] video game systems such as the Steam Machine or PlayStation 3 (until this option was removed remotely by Sony in 2010[60]), several arcade games, and embedded devices such as mobile phones, portable media players, routers, and stage lighting systems.