Operating System (OS)

An Operating System (OS) is a software that acts as an interface between computer hardware components and the user. Every computer system must have at least one operating system to run other programs.

An operating system (OS) is software that acts as a bridge between computer hardware and the user. It manages hardware resources and provides essential services and a user interface, enabling other software and applications to run efficiently. Examples include Windows, macOS, Linux, and Android.

Graphical user interface, text, chat or text message

Description automatically generated

History of operating system

1940s-1950s: Early Days

No formal OS existed; programs were run directly on hardware.
The first rudimentary "operating systems" like GMOS (General Motors Operating System) managed simple batch processes.

1960s: Multiprogramming and Timesharing

Key innovations like multitasking and time-sharing emerged.
Systems like UNIX (created at Bell Labs in 1969) became groundbreaking for their portability and flexibility.

1970s-1980s: Personal Computers Rise

Microsoft introduced MS-DOS in the early 1980s, a command-line OS for personal computers.
Apple launched its Macintosh OS in 1984, introducing graphical user interfaces to the masses.

1990s: Modern Operating Systems

Microsoft Windows gained dominance with Windows 95, offering a blend of GUI and multitasking.
Linux, an open-source OS inspired by UNIX, gained popularity for developers and enterprises.

2000s-Present: Diverse Ecosystems

Smartphones led to operating systems like iOS (Apple) and Android (Google).
Cloud-based OS and virtual machines, like ChromeOS and Windows Subsystem for Linux (WSL), became widely used.

Network Operating System (NOS) and Client Operating System (COS):

Network Operating System (NOS):

Designed to manage network resources and enable communication between devices connected to a network.
Used primarily in servers to handle tasks like file sharing, printer management, user authentication, and overall network administration.
Examples: Windows Server, UNIX, Linux Server, Novell NetWare.

Novell NetWare: 1983

Microsoft Windows Server:

Windows NT 3.1: 1993
Windows Server 2008: 2008
Windows Server 2022: 2021
Windows Server 2025: 2024

UNIX (Various Distributions):

AT&T UNIX System V: 1983
Sun Solaris: 1991

Linux-Based NOS:

Red Hat Enterprise Linux (RHEL): 2000
SUSE Linux Enterprise Server (SLES): 2000

Client Operating System (COS):

Installed on client devices like desktops, laptops, tablets, or smartphones.
Provides an interface for users to interact with applications and access resources (local or network-based).
Examples: Windows 10/11, macOS, Linux desktop distributions (like Ubuntu), Android, iOS.

Microsoft Windows

Windows 1.0: 1985
Windows 95: 1995
Windows XP: 2001
Windows 7: 2009
Windows 10: 2015
Windows 11: 2021

Apple macOS

Mac OS X 10.0 (Cheetah): 2001
macOS Mojave (10.14): 2018
macOS Monterey (12.0): 2021
macOS Ventura (13.0): 2022

Linux (Various Distributions)

Ubuntu 4.10 (Warty Warthog): 2004
Fedora Core 1: 2003
Linux Mint 1.0 (Ada): 2006

Google ChromeOS

ChromeOS: 2009

Android

Android 1.0 (Alpha): 2008
Android 14: 2023 (latest major release as of now)

1. Batch Operating System

A batch operating system processes tasks in batches without direct user interaction. Jobs are prepared, queued, and executed sequentially by the system.
- Use Case: Early computing systems where immediate user input wasn’t feasible.
Batch OS is still used today, though not on personal computers. It remains important in enterprise and large‑scale data environments:
- Banking → Daily transaction settlements, interest calculations, and statement generation.
- Payroll → Automatic salary processing for thousands of employees.
- Telecom Billing → Monthly bill generation and usage summaries.
- Government Data → Census updates, tax records, and voter lists.
- Big Data Pipelines → Overnight processing of logs, analytics, and reports.
- Scientific Research → Weather forecasting, simulations, and space research.

Key Point:

deeply integrated into backend systems

2. Time-Sharing Operating System

A time‑sharing operating system allows multiple users to use a single computer simultaneously by allocating small time slices of CPU time to each user.

Use Case: Educational institutions, early multi‑user environments.
Examples: UNIX, Windows.
Advantages: Fair resource allocation, quick response to each user.
Disadvantages: Overhead in task switching, security concerns with multiple users.

3. Distributed Operating System

A distributed operating system is an OS that manages a collection of independent computers and makes them appear to the users as a single, unified system. It coordinates resource sharing, communication, and task execution across all machines to work together seamlessly.
Common Use Cases
- Cloud Computing → Manages clusters of servers to provide seamless cloud services (e.g., Google Cloud, Microsoft Azure).
- Data Centers → Controls thousands of servers for storage, processing, and networking.
- Scientific Research → Used in simulations, weather forecasting, and space research requiring huge computing power.
- Telecommunications → Handles distributed switching and routing systems.
- E‑commerce Platforms → Supports large‑scale transaction systems like Amazon or Flipkart.
- Banking Systems → Ensures secure, distributed transaction processing across multiple branches.
- IoT Networks → Manages connected smart devices working as one ecosystem.
- Key Point: Distributed OS is best where scalability, reliability, and resource sharing across multiple computers are required.

4. Network Operating System (NOS)

A Network Operating System is designed to manage networking tasks such as file sharing, printer access, and communication between multiple devices.
- Use Case: Enterprise‑level networks, file servers, and communication systems.
- Examples: Novell NetWare, Windows Server.
- Advantages: Centralized control over network operations, security, and easy data sharing.
- Disadvantages: Complex setup and maintenance, requires skilled administrators.

5. Real-Time Operating System (RTOS)

A real‑time operating system guarantees that processing occurs within a strict time constraint, making it crucial for time‑critical tasks.
- Use Case: Robotics, aerospace, medical devices, IoT systems.
- Examples: VxWorks, FreeRTOS.
- Advantages: Predictable task execution, high reliability for time‑critical applications.
- Disadvantages: Limited multitasking capability, expensive to implement.

6. Mobile Operating System

A mobile operating system is optimized for smartphones and tablets, featuring touch interfaces and app ecosystems for portable use.
- Use Case: Consumer‑grade smartphones and tablets.
- Examples: Android, iOS.
- Advantages: Focused on user interaction and portability, provides access to a wide range of apps.
- Disadvantages: Limited hardware compatibility, frequent updates required for security.

7. Desktop/Client Operating System

A client operating system is designed for personal use, typically on desktops and laptops, with graphical interfaces and productivity tools.
- Use Case: Everyday computing, gaming, office work.
- Examples: Windows, macOS, Linux (Ubuntu).
- Advantages: User‑friendly with extensive software support, versatile for multiple use cases.
- Disadvantages: Resource‑intensive, vulnerable to malware without proper security.

8. Embedded Operating System

An embedded operating system is specifically built to run on embedded systems within devices like appliances, cars, and industrial machines.
- Use Case: Consumer electronics, automotive systems, medical equipment.
- Examples: QNX, Embedded Linux.
- Advantages: Highly optimized for specific hardware, low power consumption.
- Disadvantages: Limited flexibility in updates or modifications, restricted to a narrow range of functions.

Batch Operating System 🔗 Batch OS Image
Time‑Sharing Operating System 🔗 Time‑Sharing OS Image
Real‑Time Operating System 🔗 Real‑Time OS Image
Distributed Operating System 🔗 Distributed OS Image
Network Operating System 🔗 Network OS Image
Client Operating System 🔗 Client OS Image
Embedded Operating System 🔗 Embedded OS Image
Mobile Operating System 🔗 Mobile OS Image

What is operating system (YouTube video)

Types of operating systems (YouTube video)

The interface of an operating system (OS)

The interface of an operating system (OS) is the medium through which users interact with the system to perform tasks. It determines how efficiently and intuitively users can control and utilize system resources. Operating systems typically have two main types of interfaces:

1. Graphical User Interface (GUI)

Description: The GUI uses graphical elements like windows, icons, menus, and buttons to represent actions and tasks.
Examples: Microsoft Windows, macOS, Android.
Features:
- User-friendly with point-and-click functionality using a mouse, touchpad, or touchscreen.
- Provides visual feedback for user actions.
Advantages:
- Easy to learn, even for beginners.
- Enhances productivity by simplifying multitasking.
Disadvantages:
- Resource-intensive, requiring more memory and processing power.

2. Command-Line Interface (CLI)

Description: The CLI requires users to type specific commands to interact with the system.
Examples: UNIX Shell, PowerShell, Command Prompt.
Features:
- Primarily text-based with commands entered manually.
- Allows script writing for automating repetitive tasks.
Advantages:
- Lightweight and consumes minimal resources.
- Offers powerful control and flexibility for advanced users.
Disadvantages:
- Steep learning curve for beginners.
- Lack of visual elements can make it less engaging.

Some operating systems also feature Hybrid Interfaces that combine GUI and CLI, giving users the flexibility to switch between graphical and command-line environments. Examples include Linux distributions like Ubuntu, where users can use both a terminal (CLI) and a desktop environment (GUI).

The interface of an operating system (OS) (YouTube video)

As of 2025, the market share for desktop and laptop operating systems has evolved slightly:

Windows: Continues to dominate with approximately 71% market share, maintaining its position as the go-to OS for personal and professional use.
macOS: Holds around 16%, popular among creative professionals and users who value seamless integration with Apple devices.
Linux: Accounts for about 4%, favored by developers, tech enthusiasts, and those seeking open-source solutions

Aspect	GUI (Graphical User Interface)	CLI (Command Line Interface)
Ease of Use	Simple, beginner-friendly, click with mouse	Needs typing commands, harder for beginners
Speed	Slower because of graphics	Faster once you know commands
Precision	Less exact, more for comfort	Very exact, good for technical work
Resource Usage	Uses more memory and CPU	Uses very little memory and CPU
Input Devices	Mouse + Keyboard	Keyboard only
Error Handling	Fewer mistakes (menus help)	Easy to make typing mistakes
Multitasking	Easy with many windows	Possible but not visual
Customization	Can change themes, layouts	Limited (colors, shells)
Use Cases	Daily use, games, design, multimedia	Admin work, scripting, automation, servers

windows operating system

The Windows operating system is a family of operating systems developed by Microsoft. It is one of the most widely used operating systems in the world, known for its user-friendly interface, broad compatibility, and versatility across various devices.

Microsoft was founded on April 4, 1975 by Bill Gates and Paul Allen in Albuquerque, New Mexico. Today, it is one of the world’s most valuable companies, with a market capitalization of about $3.15 trillion (₹262 lakh crore) as of April 2026, ranking 4th globally behind Apple, Saudi Aramco, and Alphabet.

Rank	Company	Market Cap (USD)	Industry	Country
1	Nvidia	$4.50T	Semiconductors / AI	🇺🇸 USA
2	Alphabet (Google)	$3.93T	Technology	🇺🇸 USA
3	Apple	$3.84T	Technology	🇺🇸 USA
4	Microsoft	$3.55T	Technology	🇺🇸 USA
5	Amazon	$2.63T	E-commerce	🇺🇸 USA
6	TSMC	$1.65T	Semiconductors	🇹🇼 Taiwan
7	Meta Platforms	$1.62T	Social Media	🇺🇸 USA
8	Broadcom	$1.57T	Semiconductors	🇺🇸 USA
9	Saudi Aramco	$1.52T	Oil & Gas	🇸🇦 Saudi Arabia
10	Tesla	$1.44T	Automotive	🇺🇸 USA

Key Features

Graphical User Interface (GUI): Windows is recognized for its simple GUI, which uses windows, icons, and menus to make computing accessible to a wide audience.
Compatibility: Works with a vast array of hardware and software, from personal computers to enterprise-level servers.
Multi-Tasking: Allows users to run multiple applications simultaneously.
Security: Includes features like Windows Defender, BitLocker, and regular updates to protect against cyber threats.
Support for Applications: Provides a platform for a wide range of software, including productivity tools, games, and utilities.
Networking: Built-in features for networking, file sharing, and remote access.

Popular Versions

Windows 95 (1995): Introduced the Start menu and taskbar, revolutionizing user interaction.
Windows XP (2001): Renowned for stability and usability; widely adopted in homes and businesses.
Windows 7 (2009): Improved performance and aesthetics, a fan favorite.
Windows 10 (2015): Brought features like Cortana, virtual desktops, and integration with Microsoft services.
Windows 11 (2021): Redesigned interface, better multitasking, and optimized for hybrid work.

Types of Windows Operating Systems

Client OS: For personal use (e.g., Windows 10, Windows 11).
Server OS: For enterprise and server management (e.g., Windows Server 2022).
Embedded OS: Used in specialized devices like ATMs or kiosks.

Why It's Popular

Windows became so widespread due to its ease of use, extensive support for software and hardware, and adaptability to both personal and professional environments. It caters to a broad audience, from casual users to IT professionals.

(YouTube video)

Types of OS Installation

NOTE:- Installation is the process of setting up software, hardware, or an operating system on a computer or device so that it becomes ready for use.

1. Clean Installation

Meaning: Install Windows on a fresh hard drive or after deleting everything.
Use Case: When your system is slow, infected, or you want a fresh start.
Example: Installing Windows 11 on a new laptop with no previous OS.

2. Upgrade Installation

Meaning: Install a newer version of Windows over the old one, keeping files and apps.
Use Case: When you want to move from Windows 10 → Windows 11 without losing data.
Example: Upgrading Windows 10 Home to Windows 11 Home while keeping documents and apps.

NOTE:- You can only downgrade from Windows 11 to Windows 10 using the built‑in “Go back” option for the first 10 days after upgrading. After this 10‑day rollback period, Windows automatically deletes the backup files (Windows.old), and you must perform a clean installation to downgrade.

3. Dual Boot Installation

Meaning: Install two operating systems on the same computer, and choose one at startup.
Use Case: When you want to use both Windows and another OS (like Linux) on the same PC.
Example: A student installs Windows 11 and Ubuntu Linux together, so they can use Windows for daily tasks and Linux for programming.

Windows + Linux Dual Boot

Rule: Always install Windows first, then Linux.
Reason: Windows overwrites the bootloader (GRUB). If Linux is installed after Windows, GRUB will detect both OS and let you choose at startup.
Example:

Install Windows 11 on your laptop.
Then install Ubuntu Linux → GRUB menu appears → choose Windows or Ubuntu at boot.

Dual Boot with Two Windows Versions
- Rule: Install the older Windows version first, then the newer one.
- Reason: Newer Windows versions (like Windows 11) recognize older ones and add them to the boot menu. Older versions don’t recognize newer ones.
- Example:
  - Install Windows 7 first.
  - Then install Windows 11 → Boot menu lets you pick Windows 7 or Windows 11.

Step-by-Step: How to Install Windows Operating System

Step 1 – Download Windows Disk Image (ISO) (International Organization for Standardization)

Go to the official Microsoft website.
Download the Windows Media Creation Tool or Windows ISO file.
Save it on your computer. This file contains the Windows setup data.

Step 2 – Make a Bootable Pen Drive

Plug in a USB drive (minimum 8 GB).
Use software like Rufus or Media Creation Tool.
Select the downloaded ISO file.
Click Start to make the pen drive bootable. Now your USB is ready to install Windows.

Step 3 – Boot Your Computer

Insert the bootable pen drive into your PC or laptop.
Restart your computer.
Press the Boot Menu Key (depends on your brand):

How we can create bootable device

A bootable USB drive is a USB drive that allows you to use the file system stored in a flash drive to boot the computer rather than using hardware. A bootable USB drive has a lot of benefits. Install an Operating system The most common use is to install and run operating systems such as Windows and macOS linux

we have two options CMD and software (rufus), (ventoy)

Aspect	Rufus	Ventoy
Functionality	Creates a bootable USB drive for a single ISO file.	Allows multiple ISO files on a single USB drive (multiboot).
Ease of Use	Simple interface, but requires reformatting the USB drive for each new ISO.	User-friendly; no need to reformat when adding new ISOs.
Supported Formats	Supports a wide range of ISO formats, including Windows and Linux.	Supports almost all ISO formats, including Windows, Linux, and even custom ISOs.
Performance	Faster for creating single bootable drives.	Slightly slower due to multiboot capabilities.

WinRAR is a file compression and extraction tool used to reduce file size and manage archives. It supports formats like RAR and ZIP, making it easier to store or share large files.

Compress

To compress means to reduce the size of files by packing them into a smaller archive (e.g., .rar or .zip). Example: Compressing a folder before sending it by email.

Extract

To extract means to unpack or open a compressed file to access its original contents. Example: Extracting a .rar file to view documents inside.

Virtualization in Computing

Virtualization is the process of creating a virtual version of a resource — such as hardware, storage, or an operating system — instead of using the physical version directly. It allows multiple virtual environments to run on a single physical machine.

Key Points

Done using a hypervisor (like VMware, VirtualBox, Hyper‑V).
Enables running multiple operating systems on one computer.
Improves resource utilization, flexibility, and scalability.

Virtual Machine (VM)

A Virtual Machine (VM) is a software‑based computer that runs inside a physical computer. It behaves like a real computer, with its own operating system, applications, and resources, but it shares the hardware of the host machine.

Key Points

Created using virtualization software (e.g., VMware, VirtualBox, Hyper‑V).
Each VM has its own CPU, memory, storage, and network interface (virtualized).
Multiple VMs can run on one physical computer at the same time.
Useful for testing, development, training labs, and running different OS environments.

In Virtual Machines (VMs), a snapshot is a saved state of the VM at a specific point in time. It captures the VM’s disk, memory, and settings, allowing you to quickly revert back if needed—commonly used for testing, patching, or troubleshooting.

Common Uses

Testing & Development: Roll back after testing software or patches.
Troubleshooting: Capture system state before making risky changes.
Training Labs: Restore VMs to a clean state for repeated practice.

How to Take a Snapshot (VMware Example)

Right-click on the VM.
Select Snapshot → Take Snapshot.
Provide a Name & Description.

VMware Tools (often called VMTools) is a suite of utilities and drivers that improves the performance, usability, and integration of virtual machines running on VMware platforms. Without it, VMs can run, but they will lack smooth graphics, proper device drivers, and host‑guest features like copy/paste or time sync.

Windows 10 is a major version of Microsoft’s operating system, released on July 29, 2015, designed to unify the Windows experience across PCs, tablets, and smartphones. It brought back the Start Menu, introduced Microsoft Edge, Cortana, and virtual desktops, and remained one of the most widely used OS versions worldwide.

Windows 11 is Microsoft’s latest operating system, released on October 5, 2021, as the successor to Windows 10. It introduces a modernized interface with a centered taskbar, rounded corners, AI-powered features, and enhanced security, while continuing support for productivity, gaming

Key Drawbacks of Windows 10

Aspect	Windows 10 (Drawbacks)	Windows 11 (Improvements)
Support	Ended Oct 2025	Active support, AI updates
Security	No new patches, weaker protections	TPM 2.0, Secure Boot, AI security
Performance	Slow boot, resource-heavy	Optimized, faster load times
Privacy	Extensive telemetry	More transparent controls
Compatibility	Issues with new hardware/software	Designed for modern CPUs & GPUs

By CMD

create a bootable USB via CMD:

Open CMD as Administrator and launch diskpart.
Select your USB using list disk and select disk X (replace X with your USB's number).
Use clean, create partition primary, format fs=fat32 quick, active, and assign commands to prepare the drive.
Copy all files from the OS ISO to the USB drive.

Microsoft Windows 11 remains the most popular operating system from Microsoft for personal and professional use. It continues to dominate due to its user-friendly interface, robust performance, and compatibility with a wide range of software and hardware

Most Important

Aspect	Windows 10	Windows 11
Release Year	2015	2021
User Interface (UI)	Traditional design with a focus on rectangular elements.	Modern, rounded corners, redesigned Start menu in the center.
Start Menu	Left-aligned, live tiles for apps.	Centered, simpler design without live tiles.
Taskbar	Fully customizable.	Centered icons, less customization, no drag-and-drop (initially).
Performance	Designed for older and newer systems.	Optimized for faster performance with SSDs and modern processors.
Gaming Features	Basic support for gaming with Xbox app.	DirectStorage, AutoHDR, and Xbox Game Pass integration for enhanced gaming.
Multitasking	Standard snap feature with manual window resizing.	Snap layouts and groups for advanced multitasking.
Touchscreen Support	Basic support with no tablet-specific features.	Enhanced touchscreen experience and gestures.
Compatibility	Compatible with a wide range of older hardware.	Requires modern hardware like TPM 2.0 and secure boot.
Updates	Regular updates with extensive options for scheduling.	Smaller, faster updates with focus on efficiency.
Widgets	None (discontinued live tiles).	Reintroduced as a new feature, accessible from the taskbar.

Summary of Changes:

Design Overhaul: Windows 11 features a more modern, streamlined interface.
Performance Enhancements: Better for SSDs and gaming due to technologies like Direct Storage.
Hardware Requirements: Windows 11 requires newer hardware, including TPM 2.0, making it less compatible with older devices.
Productivity and Multitasking: Improved multitasking with snap layouts and virtual desktops.

Windows 10 comes in multiple editions designed for different users and devices. The most common are Home, Pro, Enterprise, and Education, but there are also specialized versions like Windows 10 Mobile, Windows 10 IoT, and regional “N” editions without media features.

Major Windows 10 Editions

Edition	Purpose / Audience
Windows 10 Home	For everyday consumers; includes core features like Cortana, Microsoft Store, and basic security.
Windows 10 Pro	For professionals and small businesses; adds BitLocker, Remote Desktop, and Group Policy management.
Windows 10 Enterprise	For large organizations; advanced security, virtualization, and deployment tools.
Windows 10 Education	For schools and universities; similar to Enterprise but tailored for academic use.
Windows 10 Mobile	Designed for smartphones and small tablets (now discontinued).
Windows 10 IoT	For embedded devices and Internet of Things hardware.
Windows 10 S	Lightweight version focused on security and performance; runs only apps from Microsoft Store.
Windows 10 N editions	Versions without Windows Media Player and related features (required by EU regulations).

Windows 10 support ends October 14, 2025, so upgrading to Windows 11 is recommended for long-term security.

Windows 11 Editions

Windows 11 Home → Designed for everyday users. Includes the new interface, gaming features like DirectStorage and AutoHDR, and integration with Microsoft Store.
Windows 11 Pro → Adds business features such as BitLocker encryption, Remote Desktop, Hyper-V virtualization, and Group Policy management.
Windows 11 Enterprise → Built for large organizations. Offers advanced security, deployment, and management tools (like AppLocker, DirectAccess, and Windows Defender Credential Guard).
Windows 11 Education → Similar to Enterprise but tailored for schools and universities, with simplified management for IT admins.
Windows 11 Pro Education → A variant of Pro with settings optimized for classroom environments.
Windows 11 Pro for Workstations → For high-performance hardware setups. Supports ReFS (Resilient File System), persistent memory, and advanced CPUs for heavy workloads.
Windows 11 Mixed Reality → Specialized edition for VR/AR devices and immersive experiences.
Windows 11 N Editions → Versions without media features like Windows Media Player (required by EU regulations).

Windows 11 Home

Designed for everyday consumers.
Includes all the core features: new Start Menu, Microsoft Store, gaming optimizations (DirectStorage, AutoHDR), and security basics like Windows Hello.
Best suited for personal use, students, and casual users.

Windows 11 Pro

Built for professionals and small businesses.
Includes everything in Home plus advanced features:
- BitLocker → Full disk encryption for better security.
- Remote Desktop → Connect to your PC remotely.
- Hyper-V → Virtualization to run multiple operating systems.
- Group Policy Management → Control settings across multiple PCs in a network.
- Assigned Access & Enterprise Mode IE → Useful for business environments.
Best suited for business users, IT admins, and power users.

Genuine Windows vs Pirated Windows

⚠️ Pirated Windows

Definition: An unauthorized copy of Windows that is illegally distributed or activated using cracks, loaders, or fake keys.
Risks:
- No official updates or security patches.
- High chance of malware, spyware, or backdoors.
- Legal consequences (software piracy is against the law).
- System instability and frequent crashes.
Use case: Often chosen to avoid paying, but it compromises security, reliability, and legality.

✅ Genuine Windows

Definition: An officially licensed copy of Windows purchased from Microsoft or authorized resellers.
Benefits:
- Regular security updates and feature upgrades.
- Access to Microsoft Store and official apps.
- Reliable performance and stability.
- Legal protection and support from Microsoft.
Use case: Recommended for personal, business, and professional use where security and compliance matter.

🔑 Major Difference

Pirated Windows → Unsafe, illegal, unsupported.
Genuine Windows → Safe, legal, supported, and future‑proof.

Comparison: Windows 10 vs Windows 11 System Requirements

In computer hardware, SoC (System on Chip) means a single integrated chip that combines most or all the essential components of a computer system into one microchip.

Components inside an SoC

CPU (Central Processing Unit) – the main processor
GPU (Graphics Processing Unit) – for graphics and image processing
Memory (RAM, ROM, Flash) – storage and working memory
I/O Controllers – USB, HDMI, Wi-Fi, Bluetooth, etc.
DSP (Digital Signal Processor) – for audio, video, and signal processing
Network Interfaces – Ethernet, wireless communication
Power Management – voltage regulators, timers, oscillators

Where SoCs are used

Smartphones, tablets, smartwatches
Embedded systems (IoT devices, smart appliances)
Laptops/netbooks (compact designs)
Automotive systems and edge computing devices

Disadvantages

Less modular (cannot replace individual components easily)
Limited flexibility compared to traditional multi-chip systems

In short: SoC = CPU + GPU + Memory + I/O + other controllers all packed into one chip, mainly used in mobile and embedded devices for efficiency.

What is TPM?

TPM (Trusted Platform Module) is a dedicated security chip built into the motherboard or CPU.
It stores encryption keys, passwords, and certificates securely.
It ensures the system boots in a trusted state and protects against tampering.

Definition user account

A user account in Windows is a profile that uniquely identifies a person using the computer. It contains their username, password, files, settings, and permissions, allowing multiple people to share the same device while keeping their data and preferences separate.

A user account is a collection of information that Windows uses to determine:
- Who is using the computer.
- What files, folders, and apps they can access.
- What system changes they are allowed to make.
Each account has a username and usually a password for login.

Types of User Accounts in Windows

Updated Windows Account Hierarchy
Local Accounts (Offline, Device-Based)
- Administrator Account → Full control over system and users.
- Standard Account → Limited permissions for daily tasks.
- Guest Account (Older Versions) → Temporary, restricted access.
Domain Accounts (Network-Based, Enterprise)
- Domain Account (Active Directory / AD DS) → Managed by IT administrators within an organization.
  - Used in office networks and servers.
  - Controlled through Group Policy and centralized authentication.
Cloud Accounts (Online, Cloud-Linked)
- Microsoft Account → Personal cloud account linked to Outlook/Hotmail.
  - Syncs settings, files, and apps across devices.
  - Enables access to OneDrive, Microsoft Store, and Office 365.
  - Ideal for home or personal users.
- Azure AD Account (Microsoft Entra ID) → Cloud-based enterprise identity for organizations.
  - Used with Microsoft 365, Azure services, and business apps.
  - Supports Single Sign-On (SSO) and Conditional Access.

Why User Accounts Matter

Personalization → Each user gets their own desktop, documents, and preferences.
Security → Prevents unauthorized access to files and system settings.
Separation → Keeps work, school, and personal data distinct.
Parental control → Allows parents to monitor or restrict children’s usage.

Steps to Create a User Account in Windows 10/11

Method 1: Using Settings

Press Windows + I to open Settings.
Go to Accounts → Family & other users.
Under Other users, click Add account.
Choose one of the following:
Microsoft account → Enter an email (Outlook, Hotmail, or any Microsoft-linked email).
Local account → Click I don’t have this person’s sign-in information → Add a user without a Microsoft account.
Enter a username and password (optional for local accounts).
Click Next → The account will be created

create a User Account via CMD

Open Command Prompt as Administrator
Press Windows + R, type `cmd`, then press Ctrl + Shift + Enter to run as administrator.
Create a new user Use the command: net user Username Password /add

net user

:: Shows all user accounts on the system

net user username /add

:: Creates a new user account (no password)

net user username password /add

:: Creates a new user account with a password

net user username /delete

:: Deletes a user account

net user username *

:: Resets the password for a user (prompts for new password)

net user "Full Name" password /add

:: Creates a user account with spaces in the name

net localgroup Administrators username /add

:: Adds a user to the Administrators group (gives admin rights)

net localgroup Administrators username /delete

:: Removes a user from the Administrators group (removes admin rights)

kiosk users in Windows. A kiosk user is a special account used in Assigned Access / Kiosk Mode, where the PC runs only one app (like a browser, or signage app).

🖥️ Where to Find / Count Kiosk Users in Windows

Settings (Windows 10/11)

Go to Settings → Accounts → Family & other users.
Scroll down to Set up a kiosk.
Here you’ll see any kiosk accounts created.
Each kiosk account is listed separately, so you can count them directly.

One‑Word Answer Questions

Which OS was created by General Motors in the 1950s?
Which OS was developed at Bell Labs in 1969?
Which Microsoft OS launched in the early 1980s?
Which Apple OS introduced GUI in 1984?
Which Windows version launched in 1995?
Which Windows version introduced the Start menu?
Which Windows version was released in 2001?
Which Windows version was released in 2009?
Which Windows version was released in 2015?
Which Windows version was released in 2021?
Which macOS version was called Cheetah?
Which macOS version launched in 2018?
Which macOS version launched in 2021?
Which macOS version launched in 2022?
Which Google OS launched in 2009?
Which mobile OS was released by Google in 2008?
Which Apple mobile OS powers iPhones?
Which OS type processes jobs sequentially?
Which OS type uses time slices for multiple users?
Which OS type manages multiple computers as one system?
Which OS type is designed for servers and networking?
Which OS type guarantees strict timing for tasks?
Which OS type is optimized for smartphones?
Which OS type is used on desktops and laptops?
Which OS type is built for appliances and cars?
Which OS interface uses icons and windows?
Which OS interface requires typed commands?
Which OS interface combines GUI and CLI?
Which NOS was released in 1983?
Which Microsoft server OS launched in 1993?
Which Microsoft server OS launched in 2008?
Which Microsoft server OS launched in 2021?
Which Microsoft server OS launched in 2024?
Which UNIX distribution launched in 1983?
Which UNIX distribution launched in 1991?
Which Windows edition is for everyday consumers?
Which Windows edition is for professionals?
Which Windows edition is for large organizations?
Which Windows edition is for schools?
Which Windows edition was discontinued for smartphones?
Which Windows edition is for embedded devices?
Which Windows edition is lightweight and runs only Store apps?
Which Windows edition excludes media features in EU?
Which Windows 11 edition is for high‑performance hardware?
Which Windows 11 edition is tailored for schools?
Which Windows 11 edition is optimized for classrooms?
Which Windows 11 edition is for VR/AR devices?
Which Windows 11 edition excludes media features?
Which Windows security tool provides disk encryption?
Which Windows tool allows remote PC connection?

In Windows, virtualization is a technology that lets your computer run multiple operating systems or isolated environments at the same time. It’s mainly used through Hyper‑V, Windows Sandbox, and other features that rely on hardware virtualization support (Intel VT‑x or AMD‑V). To use it, you must enable virtualization in your PC’s BIOS/UEFI settings

What Virtualization Means in Windows

Virtualization allows your Windows device to emulate another operating system (like Linux or Android) or run multiple virtual machines on the same hardware.
It’s essential for developers, IT admins, and advanced users who need isolated environments for testing, security, or running apps that require different OS versions.

A hypervisor (sometimes called a Virtual Machine Monitor or VMM) is software, firmware, or hardware that allows multiple operating systems to run on a single physical machine by creating and managing virtual machines (VMs)

Cost: Hyper‑V is free with Windows Pro/Enterprise; VMware usually requires a license.
Platform: Hyper‑V is Windows‑only; VMware supports Windows, Linux, and bare‑metal.
Ease of use: Hyper‑V is simpler for Windows users; VMware offers more flexibility for mixed environments.

Virtual machines (VMs) provide cost savings, flexibility, isolation, scalability, and security by allowing multiple operating systems and applications to run on a single physical machine.

Key Benefits of Virtual Machines

Resource efficiency: Multiple VMs share the same physical hardware, reducing waste and improving utilization.
Cost savings: Fewer physical servers are needed, lowering hardware, energy, and maintenance costs.
Isolation: Each VM runs independently, so failures or malware in one VM don’t affect others.
Flexibility: VMs can run different operating systems (Windows, macOS, Android, etc.) on the same hardware.
Scalability: Easy to add or remove VMs as workloads change, supporting cloud and enterprise growth.
Disaster recovery: VM snapshots and backups make recovery faster and more reliable.
Testing & development: Developers can test software in isolated environments without affecting the host system.
Security: VMs provide sandboxing, reducing risks of malware spreading across systems.
Portability: VM images can be moved across servers or cloud platforms easily.
Legacy support: Old applications can run on legacy OS versions inside VMs without needing outdated hardware

Disk Management is a Windows feature that provides a graphical interface to manage hard drives and storage devices.

Why it’s a Feature

It comes built-in with Windows (no extra software needed).
Provides system-level control over disks and partitions.
Accessible via Start → Disk Management or diskmgmt.msc.

What You Can Do with This Feature

Create partitions
Format drives
Assign/change drive letters
Shrink or extend volumes
Delete partitions
Initialize new disks

A disk partition is a logical division of a physical hard drive into separate sections, each of which acts like an independent disk to the operating system.

Purpose: Organize data, install multiple operating systems, separate system files from user files, and simplify backup/recovery.

Types:
- Primary Partition → Can host an OS or main data.
- Extended Partition → Can be subdivided into logical drives.
Partition Styles:
- MBR (Master Boot Record) → Supports up to 4 primary partitions.
- GPT (GUID Partition Table) → Supports larger disks and up to 128 partitions.
Data Organization → Keeps system files, personal files, and backups in separate sections for easy management.
Multi-OS Installation → Allows installing multiple operating systems (e.g., Windows + Linux) on the same disk.
Improved Performance → Smaller partitions can reduce file fragmentation and improve read/write speed.
Backup & Recovery → Easier to back up or restore specific partitions without affecting the whole disk.
Security & Privacy → Sensitive data can be stored in a separate partition, reducing risk of accidental deletion.

Steps to Hide a Partition:

Open Disk Management
- Press Windows + R, type diskmgmt.msc, and press Enter.
Locate the Partition
- Find the drive/partition you want to hide.
Remove Drive Letter
- Right-click the partition → select Change Drive Letter and Paths.
- Click Remove → confirm.
- The partition will no longer show up in This PC or Explorer.
To Unhide Later
- Go back to Disk Management.
- Right-click the hidden partition → Change Drive Letter and Paths → Add.
- Assign a new drive letter, and it will reappear.

Advantages of Hiding a Partition

Data Security → Prevents unauthorized users from easily accessing sensitive files.
System Protection → Hides system partitions (like recovery drives) so users don’t accidentally delete or modify important files.
Organizational Control → Keeps partitions reserved for backups or special use hidden from everyday view.

A File System is a structured way to store and retrieve data. It decides how files are named, stored, accessed, and managed on a disk.

FAT32 → Older Windows systems, USB drives.
NTFS → Modern Windows systems, supports permissions & encryption.
ext4 → Common in Linux.
APFS → Apple macOS and iOS devices.

Feature	FAT32	NTFS	exFAT
Introduced	1996	1993 (Windows NT)	2006
Max File Size	4 GB	16 TB+ (practically unlimited)	16 EB (Exabytes)
Max Partition Size	32 GB (Windows default), up to 2 TB with tools	16 TB+	128 PB (Petabytes)
Compatibility	Works with almost all OS (Windows, macOS, Linux, cameras, consoles)	Best for Windows; macOS read-only by default; limited device support	Widely supported across modern OS, better than NTFS
Security	No file permissions or encryption	Supports permissions, encryption, compression, quotas	No advanced security features
Best Use	USB drives, SD cards, small storage	Internal hard drives, system drives, Windows OS	Large external drives, flash drives, cross-platform use

A Partition Style in Windows is the method used to store information about partitions on a disk. It defines how the disk is divided, how partitions are described, and how the operating system reads/writes data.

Partition Style	Disk Size Limit	Partition Limit	Boot Mode	Features	Best Use
MBR (Master Boot Record)	Up to 2 TB	Max 4 primary partitions (or 3 + 1 extended)	Legacy BIOS	Simple, widely compatible, but limited	Older systems, small disks
GPT (GUID Partition Table)	More than 2 TB (up to 9.4 ZB)	Up to 128 partitions	UEFI	CRC protection, backup partition table, modern standard	Modern PCs, large disks

CRC (Cyclic Redundancy Check) is an error-detecting code used in digital networks and storage devices to check the integrity of data.

It ensures that the data received or stored is the same as the data sent, without corruption.

A BIOS style (firmware interface) is the system software that initializes hardware during boot and provides runtime services for operating systems. Windows supports two styles: Legacy BIOS and UEFI.

Type	Full Form	Partition Style Supported	Disk Size Limit	Features	Best Use
Legacy BIOS	Basic Input Output System	MBR (Master Boot Record)	Up to 2 TB	Old standard, text-only interface, slower boot, no advanced security	Older PCs, small disks
UEFI	Unified Extensible Firmware Interface	GPT (GUID Partition Table)	More than 2 TB (up to 9.4 ZB)	Modern GUI interface, faster boot, Secure Boot, supports large disks, pre-boot apps	Modern PCs, large disks

Unit	Size
Bit	0 or 1
Nibble	4 bits
Byte	8 bits
Kilobyte (KB)	1,024 Bytes
Megabyte (MB)	1,024 KB
Gigabyte (GB)	1,024 MB
Terabyte (TB)	1,024 GB
Petabyte (PB)	1,024 TB
Exabyte (EB)	1,024 PB
Zettabyte (ZB)	1,024 EB
Yottabyte (YB)	1,024 ZB

GPO

HDFC

PASSWORD BREAK

DATA RECOVERY

Unit	Size	Explanation
Bit	Smallest unit (0 or 1)	Binary digit
Nibble	4 bits	Half a byte
Byte	8 bits	Stores one character (like “A”)
Kilobyte (KB)	1,024 bytes	Small text file
Megabyte (MB)	1,024 KB	MP3 song ≈ 3–5 MB
Gigabyte (GB)	1,024 MB	Movie ≈ 1–2 GB
Terabyte (TB)	1,024 GB	Large hard drive
Petabyte (PB)	1,024 TB	Data centers
Exabyte (EB)	1,024 PB	Global internet traffic scale
Zettabyte (ZB)	1,024 EB	Massive cloud storage
Yottabyte (YB)	1,024 ZB	Theoretical future scale

BitLocker is a Windows security feature that protects your data by encrypting entire drives. This encryption ensures that if someone tries to access the disk offline (for example, by removing the hard drive and connecting it to another computer), they cannot read its contents without the proper decryption key. BitLocker is especially useful if your device is lost or stolen, as it keeps sensitive information secure. It integrates with the operating system for easy setup and management, and works best with a Trusted Platform Module (TPM) chip, which verifies that the system hasn’t been tampered with before allowing access.

Windows Edition	BitLocker Availability	Notes / Features
Windows Home	❌ Not Available	Only basic device encryption (limited)
Windows Pro	✅ Available	Full drive encryption, BitLocker To Go, TPM support
Windows Education	✅ Available	Same as Pro, plus centralized management for schools
Windows Enterprise	✅ Available	Advanced management, network unlock, group policy integration

Go to Control Panel → Manage BitLocker.
Select the drive you want to encrypt.
Click Turn on BitLocker.
Choose an unlock method (password/PIN/USB).
Save the recovery key safely.
Select encryption type (used space only or entire drive).
Click Start Encrypting.

ninit

The BitLocker Recovery Key is a special 48-digit numerical password that allows you to unlock your encrypted drive if you forget your password, lose your smart card

Disk Quota – Definition

A disk quota is a storage allocation limit applied to users, groups, or projects on a file system.

It ensures fair usage of storage resources and prevents any single user from consuming all available space.

Types of Quotas

Disk space (block quota): Limits the amount of storage used.
Number of files (inode quota): Limits how many files/directories can be created.
Soft quota: A warning level; users are notified when nearing the limit.
Hard quota: A strict limit; users cannot exceed it.

⚙️ Configuration Steps

Open File Explorer → Press Windows + E.
Right-click the Drive (e.g., C:) → Select Properties.
Go to Quota Tab → Click Show Quota Settings.
Enable Quota Management → Check:
- Enable quota management
- Deny disk space to users exceeding quota limit (optional, makes it strict).
Set Limits →
- Select Limit disk space to: and enter the maximum storage (e.g., 200 GB).
- Set a Warning level (e.g., 150 GB) so users get notified before hitting the limit.
Apply Settings → Click Apply → OK.
For Specific Users →
- In Quota Settings, click Quota Entries.
- Add a new user and assign custom limits.
- Example: User A → 50 GB, User B → 100 GB.
Restart PC → Changes take effect after restart.

Temp → This is the general temporary folder where Windows and applications store short‑term files.
%Temp% → This is an environment variable that points directly to the current user’s Temp folder. Typing %temp% in the Run dialog (Win+R) opens it.
Prefetch → This folder stores prefetch data that helps Windows load frequently used applications faster.

CMD is a built-in Windows utility that allows users to interact with the operating system using text-based commands instead of the graphical interface. It is also known as the Windows Command Processor.

Feature	CMD	PowerShell
Origin	Legacy tool from MS-DOS era	Introduced in 2006, built on .NET
Output	Plain text	Objects with properties & methods
Commands	Simple commands & batch files	Advanced cmdlets, scripting language
Use Cases	File management, quick diagnostics, legacy support	Automation, system administration, cloud integration
Flexibility	Limited to basic tasks	Highly flexible, supports remote management & complex scripts
Integration	Works with Windows commands only	Deep integration with Windows + .NET + WMI
Best For	Beginners, troubleshooting, recovery	IT pros, administrators, automation, enterprise tasks

CMD is lightweight, simple, and good for basic commands or legacy scripts.
PowerShell is modern, powerful, and designed for automation, scripting, and enterprise-level management.

cd → Change directory
Example: cd Documents
dir → List files and folders in the current directory
Example: dir
mkdir → Create a new folder
Example: mkdir MyFolder
del → Delete a file
Example: del file.txt
copy → Copy files from one location to another
Example: copy file.txt D:\Backup
move → Move files to another location
Example: move file.txt D:\Data
cls → Clear the screen
Example: cls
exit → Close the Command Prompt
Example: exit
ipconfig → Show network configuration
Example: ipconfig
ping → Test network connectivity
Example:

echo → Display messages or turn command echoing on/off Example: echo Hello World
type → Show the contents of a text file Example: type notes.txt
attrib → Change file attributes (read-only, hidden, etc.) Example: attrib +r file.txt
chkdsk → Check disk for errors Example: chkdsk C:
sfc → System File Checker (repairs corrupted system files) Example: sfc /scannow
tasklist → Show running processes Example: tasklist
taskkill → Kill a running process Example: taskkill /IM notepad.exe /F
shutdown → Shut down or restart the computer Example: shutdown /r /t 0
netstat → Show active network connections Example: netstat -an
nslookup → Query DNS records Example: nslookup google.com
fc → Compare two files Example: fc file1.txt file2.txt
assoc → Display or change file associations Example: assoc .txt=txtfile
color → Change text and background color in CMD Example: color 0A (green text on black background)
comp → Compare contents of two files Example: comp file1.txt file2.txt
driverquery → List all installed drivers Example: driverquery
hostname → Display the computer’s name Example: hostname
net → Manage network resources (users, shares, services) Example: net user
path → Display or set search path for executables Example: path
prompt → Change the CMD prompt text Example: prompt MyPC$G
set → Display, set, or remove environment variables Example: set PATH
systeminfo → Show detailed system configuration Example: systeminfo
ver → Show Windows version Example: ver

wmic → Windows Management Instrumentation Command-line (advanced system info) Example:
arp → Show or modify ARP table Example: arp -a
bootcfg → Edit boot configuration (older Windows versions) Example: bootcfg /query
cipher → Manage encryption on NTFS drives Example: cipher /e file.txt
diskpart → Disk partition management tool Example: diskpart
driverquery → List installed drivers Example: driverquery /v
netsh → Configure network settings Example: netsh wlan show profiles
pathping → Network path + ping test Example: pathping google.com
reg → Access Windows Registry from CMD Example: reg query HKCU\Software
robocopy → Advanced file copy tool Example: robocopy C:\Data D:\Backup /MIR
sc → Manage Windows services Example: sc query
schtasks → Schedule tasks Example: schtasks /create /tn "Backup" /tr backup.bat /sc daily /st 10:00

whoami → Show current logged-in user Example: whoami
Shutdown: shutdown /s /t 0 Restart: shutdown /r /t 0 Logoff: shutdown /l

In Windows, file permissions are rules that control who can access a file or folder and what actions they can perform. These permissions are part of the NTFS file system security.

Read → Allows viewing file contents.
Write → Allows modifying or adding data.
Read & Execute → Allows running executable files.
Modify → Allows reading, writing, and deleting files.
Full Control → Complete access, including changing permissions.

How to Set Permissions

Right-click file/folder → Properties
Go to Security tab
Click Edit → Add/Remove users or groups
Assign permissions (Allow/Deny)

Windows activation is the process that verifies your copy of Windows is genuine and properly licensed. It links either a product key (25‑character code) or a digital license to your computer’s hardware configuration.

Product Key → Comes with boxed copies, OEM PCs, or authorized purchases.
Digital License → Linked to your Microsoft account; doesn’t require entering a key.

Pirated Windows

A copy of Windows that is illegally distributed or activated without a genuine Microsoft license.
How it works:
- Using cracked product keys.
- Modifying activation files (KMS activators, loaders).
- Downloading Windows ISO from unofficial sources.
Risks:
- ❌ No official updates or security patches.
- ❌ Higher chance of malware/viruses.
- ❌ Legal issues (software piracy).
- ❌ System instability and crashes.
Difference from Genuine Windows:

Genuine Windows → Activated via Microsoft product key or digital license.
Pirated Windows → Activated via illegal cracks, often unstable.

Pirated Windows Usage Statistics (2026)

Global Piracy Rate (all software): ~40% of software in use worldwide is pirated.
Windows Share: Windows accounts for ~79% of pirated desktop software installs.
Annual Losses: Software piracy costs the industry ~$68 billion per year.
Demographics:
- 68% of pirates are aged 18–34.
- 72% are employed individuals.
- 29% are students.
Distribution: 82% of pirated software is spread via peer‑to‑peer (P2P) networks.

Top Piracy Hotspot Countries (2025–2026)

According to Revenera’s compliance intelligence data:

China
Russia
India
United States
Brazil
Germany
Vietnam
Hong Kong
France
Iran

Risks of Using Pirated Windows

❌ No official updates or security patches.
❌ Malware infections and data theft.
❌ Legal penalties (average fines ~$45,000 per case).
❌ System instability and crashes.

Why Microsoft Doesn’t Take Action Against Every Pirated Windows User

Scale Problem
- Nearly 40% of global software is pirated, and Windows is the biggest victim.
- Tracking every single user worldwide is technically impossible — billions of devices, many offline or hidden behind networks.
Legal & Jurisdiction Limits
- Microsoft can’t directly prosecute individuals in every country.
- Laws differ: in some regions, enforcement against end‑users is weak or nonexistent.
- Instead, they target large distributors of pirated copies.
Business Strategy
- Microsoft focuses on enterprise compliance (companies, schools, governments) because piracy there causes bigger financial losses.
- For individuals, they often push low‑cost or free upgrade offers (like Windows 10 free upgrade from 7/8).
Technical Controls
- Pirated Windows copies often show “Activate Windows” watermark.
- Restricted personalization (no themes, wallpapers).
- No guaranteed security updates.
- Microsoft uses Windows Genuine Advantage (WGA) checks to detect piracy.
Indirect Action

Instead of punishing individuals, Microsoft makes pirated copies less useful and less secure, encouraging users to switch to genuine versions.
They also partner with governments (like India, China) to promote legal software adoption.

irm https://get.activated.win | iex