Operating System (OS)

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An operating system (OS) is software that manages computer hardware and software resources and provides common services for computer programs.

• 4 Types
  • network operating systems
  • server operating systems
  • mobile operating systems
  • personal computer operating systems

Utility software extends the capabilities of an operating system.

The kernel contains the operating system components that perform the basic functions required by the computer installation.

• file manager
• memory manager

A user account is a record within the operating system with information such as a name, password, and user privileges (e.g., administrator vs. standard user).

• controls access to the system and resources.

The memory manager manages the system’s primary main memory.

• needs to find and assign the main memory space for each of the processes and restrict the actions of each process to the memory space allocated to that program

When more main memory space is needed, the memory manager can create an illusion of additional space by rotating programs and data between the primary and secondary memory, a technique called paging.

The additional memory space created in secondary memory by paging is referred to as virtual memory.