Operating Systems

Operating systems are programs that manage computer hardware. The operating system creates a certain environment for running and controlling user activities. For this purpose, in a sense, it supervises the planning and thus allocates processor time to specific tasks. It also deals with the control and allocation of operational memory for tasks that are currently running. It provides the mechanisms that are needed to synchronize tasks and to switch between them.

The operating system deals with various computer-connected devices such as a printer, scanner, or hard drive. At the same time, it provides access to the hardware programs running on the computer. Additional tasks of the operating system are file management and controlling network connections.

The operating system consists of three main elements. The first is the system kernel responsible for the tasks performed. It controls a number of modules:

• a processor time scheduler that sets and schedules the time the task will be performed.
• a task switcher, which as the name implies is responsible for switching between tasks running simultaneously.
• a synchronization module,
• a module for supporting interrupts and device management,
• a memory module that provides memory protection,
• other modules that depend on the purpose of the operating system.

The second element after the kernel is the shell. It is a program that is responsible for system communication with users. The last and the third element of the operating system is the file system. It creates a structure of data recorded on media, such as hard drives or CDs.

Types of Operating Systems

The most important operating systems on the market include desktop operating systems:

• Unix and Unix–like,
• BSD systems,
• macOS,
• the systems from the Linux family,
• Microsoft Windows,
• as well as mobile operating systems: Android, iOS, Windows Mobile, Blackberry, and others.