Functions of an Operating System

An Operating System (OS) is responsible for managing hardware and software resources while providing services to users and applications. Below are its key functions:

1. Process Management

  • Creates, schedules, and terminates processes (running programs).
  • Uses CPU scheduling algorithms (e.g., Round Robin, FCFS) for multitasking.
  • Manages inter-process communication and synchronization.

2. Memory Management

  • Allocates and deallocates memory for processes.
  • Uses techniques like paging, segmentation, and virtual memory to optimize RAM usage.
  • Prevents memory leaks and ensures efficient memory allocation.

3. File System Management

  • Organizes, stores, retrieves, and manages data in files and directories.
  • Supports different file systems (e.g., NTFS, FAT32, EXT4).
  • Provides file permissions and access control for security.

4. Device Management

  • Controls hardware devices like keyboards, printers, and storage devices.
  • Uses device drivers to enable communication between hardware and software.
  • Implements buffering, caching, and spooling for efficient device operations.

5. Security & Access Control

  • Protects data and resources from unauthorized access.
  • Implements user authentication (passwords, biometrics) and encryption.
  • Manages access permissions for files and programs.

6. User Interface (UI) Management

  • Provides an interface for user interaction:
  • Command-Line Interface (CLI) (e.g., Linux Terminal, Windows CMD)
  • Graphical User Interface (GUI) (e.g., Windows, macOS)

7. Job Scheduling & Resource Allocation

  • Prioritizes tasks and assigns system resources efficiently.
  • Uses algorithms like First Come First Serve (FCFS), Shortest Job Next (SJN), and Round Robin for scheduling.
  • Ensures fair resource allocation among users and processes.

8. Networking Management

  • Manages network connections and communication between computers.
  • Supports protocols like TCP/IP for internet and LAN communication.
  • Enables file sharing, remote access, and cloud integration.

9. Error Detection & Handling

  • Detects system failures and takes corrective actions (e.g., restarting crashed programs).
  • Logs errors for troubleshooting.
  • Prevents system crashes by handling hardware and software faults.

10. Multitasking & Multithreading

  • Multitasking: Runs multiple programs simultaneously (e.g., browsing while downloading).
  • Multithreading: Allows a single program to execute multiple tasks at once (e.g., running multiple tabs in a browser).