To understand the tasks of an operating system, it is necessary to have some knowledge of computer systems. In this text, there will be no detailed description of the constructions of computers, but we will look at some key components of the computer system and show why these need to be administered by an operating system.
A processor executes the instructions that a computer program is comprised of. The processor is therefore the central unit of program execution.
Several applications are often simultaneously executed on a computer. It is therefore a task for the operating system to launch programs and allocate time for programs in one or more processors.
The applications running are loaded into a computer’s memory for storage. Consequently, it is therefore necessary to keep track of where in the memory different data resides. In addition, there is a need to keep track of which parts of the memory are available and which parts are in use. Managing computer memory is a task for the operating system.
Files are stored on a hard disk. The operating system keeps track of where files on the hard disk are situated, as well as what parts of the hard disk are in use and what parts are not in use.
Input/output means communication between software applications and screen, keyboard, mouse and similar devices. The operating system takes care of the input/output to make it easier for applications to communicate with different drivers for input/output devices.
In addition to creating services for the computer system, it is a task for an operating system to provide a user interface for the computer. Windows has a graphical user interface in which the user uses the keyboard, mouse and touch screen to interact with applications.
