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).