Operating System



Apr 01, 2021 What Is the Purpose of an Operating System? Operating systems contain and manage all the programs and applications that a computer or mobile device is able to run, which means managing the device’s software and hardware functions. The functions of an OS include. Operating system. The 'Operating system' provides utilities to optimize your system, monitor its operation and manage your files.

  • Operating System Tutorial
  • OS - Exams Questions with Answers
  • Operating System Useful Resources
  • Selected Reading

An Operating System (OS) is an interface between a computer user and computer hardware. An operating system is a software which performs all the basic tasks like file management, memory management, process management, handling input and output, and controlling peripheral devices such as disk drives and printers.

Some popular Operating Systems include Linux Operating System, Windows Operating System, VMS, OS/400, AIX, z/OS, etc.

Definition

An operating system is a program that acts as an interface between the user and the computer hardware and controls the execution of all kinds of programs.

Following are some of important functions of an operating System.

  • Memory Management
  • Processor Management
  • Device Management
  • File Management
  • Security
  • Control over system performance
  • Job accounting
  • Error detecting aids
  • Coordination between other software and users

Memory Management

Memory management refers to management of Primary Memory or Main Memory. Main memory is a large array of words or bytes where each word or byte has its own address.

Main memory provides a fast storage that can be accessed directly by the CPU. For a program to be executed, it must in the main memory. An Operating System does the following activities for memory management −

  • Keeps tracks of primary memory, i.e., what part of it are in use by whom, what part are not in use.

  • In multiprogramming, the OS decides which process will get memory when and how much.

  • Allocates the memory when a process requests it to do so.

  • De-allocates the memory when a process no longer needs it or has been terminated.

Processor Management

System

In multiprogramming environment, the OS decides which process gets the processor when and for how much time. This function is called process scheduling. An Operating System does the following activities for processor management −

  • Keeps tracks of processor and status of process. The program responsible for this task is known as traffic controller.

  • Allocates the processor (CPU) to a process.

  • De-allocates processor when a process is no longer required.

Device Management

An Operating System manages device communication via their respective drivers. It does the following activities for device management −

  • Keeps tracks of all devices. Program responsible for this task is known as the I/O controller.

  • Decides which process gets the device when and for how much time.

  • Allocates the device in the efficient way.

  • De-allocates devices.

File Management

A file system is normally organized into directories for easy navigation and usage. These directories may contain files and other directions.

An Operating System does the following activities for file management −

  • Keeps track of information, location, uses, status etc. The collective facilities are often known as file system.

  • Decides who gets the resources.

  • Allocates the resources.

  • De-allocates the resources.

Other Important Activities

Following are some of the important activities that an Operating System performs −

  • Security − By means of password and similar other techniques, it prevents unauthorized access to programs and data.

  • Control over system performance − Recording delays between request for a service and response from the system.

  • Job accounting − Keeping track of time and resources used by various jobs and users.

  • Error detecting aids − Production of dumps, traces, error messages, and other debugging and error detecting aids.

  • Coordination between other softwares and users − Coordination and assignment of compilers, interpreters, assemblers and other software to the various users of the computer systems.

Operating System Examples

An operating system is a specialized collection of software that stands between a computer’s hardware architecture and its applications., For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware., The dominant desktop operating system is Microsoft Windows with a market share of around 82.74%., A single-tasking system can only run one program at a time, while a multi-tasking operating system allows more than one program to be running simultaneously., Single-user operating systems have no facilities to distinguish users, but may allow multiple programs to run in tandem., The development of networked computers that could be linked and communicate with each other gave rise to distributed computing., A real-time operating system is an operating system that guarantees to process events or data by a specific moment in time., Early computers were built to perform a series of single tasks, like a calculator., The first microcomputers did not have the capacity or need for the elaborate operating systems that had been developed for mainframes., MacOS is a line of open core graphical operating systems developed, marketed, and sold by Apple Inc..