An operating system is a compilation of computer programs that manages the system resources of a computer such as memory, hard drives, input and output devices and makes these application programs available. The operating system thus forms the interface between the hardware components and the application software of the user. Operating systems generally consist of a kernel (German: Kern), which manages the hardware of the computer, as well as special programs, which take on different tasks when started. These tasks include loading device drivers. Operating systems can be found in almost all types of computers: as real-time operating systems on process computers and embedded systems, on personal computers, tablet computers, smartphones and on larger multiprocessor systems such as B. servers and mainframes.
The tasks of an operating system can be summarized as follows: user communication; Loading, executing, interrupting and exiting programs; Management and allocation of processor time; Management of internal storage space for applications; Management and operation of the connected devices; Protective functions e.g. B. by access restrictions. The weighting between these tasks changed over time, in particular protection functions such as memory protection or limited user rights are now more important than in the 1990s. This makes systems generally more robust, e.g. B. the number of program and system crashes and also makes the system more stable against external attacks, such as computer viruses.