An operating system is an interface between hardware and user an OS is responsible for the management and coordination of activities and the sharing of the resources of the computer. The operating system acts as a host for computing applications that are run on the machine.
As a host, one of the purposes of an operating system is to handle the details of the operation of the hardware. This relieves application programs from having to manage these details and makes it easier to write applications. Operating systems offer a number of services to application programs and users.
Almost all computers including handheld computers, desktop computers, supercomputers, video game consoles as well as some robots, domestic appliances dishwashers, washing machines, and portable media players use an operating system through application of some type.
Some of the oldest models may however use an embedded operating system that may be contained on a compact disk or other data storage device. Applications access these services through application programming interfaces or system calls. Whether the user interface should be included as part of the operating system is a point of contention.