Understanding operating system

Understanding an Operating System (OS) involves knowing its purpose, components, and functions. Here's a simplified overview:

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What is an Operating System?

An Operating System is system software that acts as an intermediary between computer hardware and the user. It manages hardware resources and provides services for computer programs.

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Main Functions of an Operating System:

1. Process Management:

   • Manages running applications (called processes)
   • Allocates CPU time to each process
   • Handles multitasking and process synchronization

2. Memory Management:

   • Tracks each byte of memory
   • Allocates/deallocates memory space as needed
   • Ensures programs do not interfere with each other

3. File System Management:

   • Organizes, stores, retrieves, and manages data on storage devices
   • Controls access to files and directories

4. Device Management:

   • Manages device communication via drivers
   • Controls input/output devices (keyboard, mouse, printer, etc.)

5. User Interface:

   • Provides a way for users to interact with the computer (CLI or GUI)

6. Security & Access Control:

   • Protects data from unauthorized access
   • Manages user permissions

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Types of Operating Systems:

• Batch OS: Processes batches of jobs with little/no user interaction.
• Time-Sharing OS: Allows multiple users to use the system interactively.
• Distributed OS: Coordinates a group of computers to work as one.
• Real-Time OS (RTOS): Responds to inputs immediately, used in embedded systems.
• Mobile OS: Designed for smartphones and tablets (e.g., Android, iOS).

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Examples of Operating Systems:

• Desktop/Server: Windows, Linux, macOS, Unix
• Mobile: Android, iOS
• Embedded/RTOS: FreeRTOS, VxWorks