What is the main function of an operating system?

An operating system (OS) is the core software that controls and manages the computer’s hardware and software. Its main function is to act as an interface between the user, applications, and the computer hardware. It ensures all system components—such as the CPU, memory, storage devices, and input/output hardware—work together smoothly.

For example, when you run a program, the operating system allocates memory, assigns processing time, and manages files and data access. It also handles communication between software applications and physical devices like printers, keyboards, and monitors.

In addition to resource management, an OS performs other critical tasks:

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  It allows multiple programs to run simultaneously (multitasking).

  
  


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  It provides a graphical user interface (GUI) or command-line interface (CLI) for user interaction.

  
  


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  It manages file systems and access permissions.

  
  


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  It ensures security by controlling user access and monitoring system activity.

  
  

  While compiling programs, designing graphics, and browsing the internet are common computer tasks, these are carried out by specific applications—not by the operating system itself. The OS simply provides the environment and tools that make those applications run efficiently.

  
  

  That’s why the main function of an operating system is to manage all hardware and software resources of a computer system.