The base program that manages a computer and gives control of the functions designed for general purpose usage, not for specific applications. Common examples are MS-DOS, Windows and Linux for PCs, OSX for Apple Macintosh and UNIX. The operating system provides the connections to keyboards, networks, storage and displays. For actual use, such as word processing, there are specific applications software packages that run on top of the operating system. For high performance applications such as video editing the developer needs to minimise the use of the OS to ensure that the most compute cycles can be available for the application. Efficient use of the OS and its facilities are key to producing smooth and interactive interfaces between operator and machine.
See also: Threading