Operating Systems

An operating system (OS) is a fundamental software component that manages computer hardware and provides a platform for running applications. It acts as an intermediary between the hardware and software, facilitating communication and coordination between them. Operating systems are essential for the operation of computers, mobile devices, servers, and embedded systems.


Here is the purpose of operating systems:

  • An operating system provides an interface for users to interact with the computer and execute applications.
  • It manages system resources such as memory, processors, storage devices, and input/output devices, allocating them efficiently to running processes.
  • The operating system ensures the security and integrity of data, protects against unauthorized access, and provides mechanisms for data backup and recovery.
  • It enables multitasking, allowing multiple programs to run concurrently, and provides mechanisms for process synchronization and communication.
  • The operating system facilitates file management, organizing data into a hierarchical structure and providing access controls.
  • It enables device drivers to communicate with hardware components, ensuring proper functioning and compatibility.
  • The operating system provides a foundation for software development by offering application programming interfaces (APIs) and libraries.


There are various types of operating systems.

  • Single-User, Single-Tasking: These operating systems support only one user and allow execution of one task at a time. Examples include early versions of MS-DOS.
  • Single-User, Multi-Tasking: These operating systems enable a single user to run multiple tasks simultaneously. Examples include Windows, macOS, and Linux distributions.
  • Multi-User: These operating systems support multiple users simultaneously, with each user having independent sessions and resources. Examples include UNIX-based systems and mainframe operating systems.
  • Real-Time: Real-time operating systems prioritize timely execution of tasks, commonly used in applications with strict timing requirements, such as industrial control systems or robotics.
  • Embedded: Embedded operating systems are designed for specific devices or embedded systems, such as those found in smartphones, tablets, smart TVs, and IoT devices.


Operating system has various components:

  • Kernel: The kernel is the core component of an operating system, responsible for managing system resources and providing essential services.
  • File System: The file system organizes and manages files and directories on storage devices, providing access and data management capabilities.
  • Device Drivers: Device drivers facilitate communication between the operating system and hardware devices, enabling their proper functioning.
  • User Interface: The user interface allows users to interact with the operating system, providing a graphical or command-line interface.
  • Utilities: Operating systems include various utilities for tasks such as system management, file manipulation, and diagnostics.

Common Operating Systems

Here are some common operating systems.

  • Windows: Developed by Microsoft, Windows is widely used in desktop and laptop computers, providing a user-friendly interface and broad software compatibility.
  • macOS: Developed by Apple, macOS is designed for Apple Macintosh computers, emphasizing integration with Apple hardware and software.
  • Linux: Linux is an open-source operating system widely used in servers and embedded systems, offering customization, security, and stability.
  • iOS: Developed by Apple, iOS is the operating system for iPhones, iPads, and iPod Touch devices, offering a seamless ecosystem and optimized performance.
  • Android: Android, developed by Google, is an open-source operating system used in smartphones, tablets, and other devices, offering a vast app ecosystem and customization options.

Operating systems are a vital foundation for computing, providing the necessary software infrastructure to harness the power of hardware resources and enable the execution of various applications. They play a crucial role in managing system resources, providing user interfaces, ensuring security, and facilitating efficient operation of computers and devices.

Here is more information about specific operating systems.


  • Features: Windows is a widely used operating system developed by Microsoft. It offers a user-friendly interface, extensive software compatibility, and a broad range of applications. Windows provides features such as multitasking, virtual desktops, Cortana voice assistant, gaming capabilities, and a vast selection of software and games.
  • Installation: Windows can be installed by obtaining a licensed copy of the operating system, either through a physical installation disc or a digital download. The installation process involves booting from the installation media, following on-screen prompts, and configuring system settings.
  • File Structure: Hierarchical file system known as the New Technology File System (NTFS). The file structure consists of drives, which are typically represented by letters (e.g., C: for the primary hard drive). Drives contain directories (also called folders), which can further contain files or additional subdirectories. The file path in Windows is specified using backslashes () to separate directories (e.g., C:\Users\Username\Documents\File.txt).
  • Customization: Windows allows customization through personalized settings, desktop backgrounds, themes, and taskbar configurations. Users can customize the appearance, privacy settings, accessibility options, and more.
  • Security: Windows includes built-in security features such as Windows Defender antivirus, Windows Firewall, and regular security updates. Additional security measures like BitLocker encryption and Windows Hello for biometric authentication are available in certain editions.
  • Compatibility: Windows has broad software and hardware compatibility, with a vast library of applications and drivers available. It supports a wide range of devices, peripherals, and external hardware.
  • Optimization: Windows provides various optimization features, including disk cleanup, defragmentation, performance monitoring, and power management settings. Users can also customize startup programs, manage system resources, and utilize task manager for troubleshooting.


  • Features: Linux is an open-source operating system with a strong emphasis on customization, security, and stability. It offers a wide range of distributions (distros) catering to different user needs. Linux is known for its robust command-line interface, support for programming and development, and extensive server capabilities.
  • Installation: Linux can be installed by downloading a distribution ISO file and creating a bootable USB drive or DVD. The installation process may vary slightly depending on the chosen distribution but generally involves booting from the installation media and following the on-screen instructions.
  • File Structure: utilize the Linux File System (ext4) by default. Follows a tree-like file structure, starting from the root directory (/). Directories are organized hierarchically, and file paths are specified using forward slashes (/) to separate directories (e.g., /home/username/Documents/File.txt). Linux also allows mounting additional devices or partitions into the file system hierarchy.
  • Customization: Linux provides extensive customization options, allowing users to choose different desktop environments, window managers, and themes. Users can customize nearly every aspect of the system, including appearance, behavior, and installed software packages.
  • Security: Linux is renowned for its strong security features. It benefits from a robust permission system, package management with digital signatures, and frequent security updates. Linux distributions often come with built-in firewalls and security tools to protect against threats.
  • Compatibility: Linux supports a wide range of hardware and offers compatibility with various file systems. While Linux has grown in popularity for desktop use, it is widely used in server environments and embedded systems.
  • Optimization: Linux provides tools for system optimization, including package managers for efficient software installation and updates, performance monitoring tools, and command-line utilities for system tuning and troubleshooting.

Mount folders with ssh:

Additional links:

Mac OS

  • Features: Mac OS, developed by Apple, is known for its seamless integration with Apple hardware, sleek design, and intuitive user interface. It offers features such as Siri voice assistant, iCloud synchronization, optimized power management, and a wide range of productivity applications.
  • Installation: Mac OS is pre-installed on Apple Macintosh computers and comes with a simple setup process. Users can upgrade to the latest version of Mac OS through the Mac App Store.
  • File Structure: Employs the Apple File System (APFS) since macOS High Sierra. The file structure is similar to Linux, with a hierarchical directory tree starting from the root directory (/). File paths in macOS also use forward slashes (/) to separate directories (e.g., /Users/username/Documents/File.txt). Mac OS also supports disk partitioning and uses the HFS+ file system for compatibility with older versions.
  • Customization: Mac OS provides customization options for desktop backgrounds, screensavers, and various system preferences. Users can personalize their Mac experience by arranging icons, customizing the dock, and adjusting system settings.
  • Security: Mac OS incorporates robust security measures such as Gatekeeper, which verifies the authenticity of downloaded applications, and FileVault, which enables disk encryption. Regular security updates are released to address vulnerabilities and protect user data.
  • Compatibility: Mac OS is designed exclusively for Apple hardware, ensuring a high level of compatibility and optimized performance. However, it may have limitations when it comes to software compatibility with certain applications or games.
  • Optimization: Mac OS includes built-in optimization features such as energy-saving settings, memory management, and storage optimization tools. It also provides activity monitor utilities to monitor system performance and diagnose issues.


  • Features: iOS is Apple's mobile operating system designed for iPhones, iPads, and iPod Touch devices. It offers a user-friendly interface, app ecosystem, seamless integration with other Apple devices, and features like Siri, Face ID, and Touch ID.
  • Installation: iOS is pre-installed on Apple mobile devices and is updated through over-the-air software updates provided by Apple.
  • File Structure: uses the Apple File System (APFS) since iOS 10. The file structure in iOS is organized similarly to macOS. Applications are sandboxed, meaning each app has its own isolated storage area. Users typically interact with their files within the app's designated storage area, and accessing files across apps is restricted unless explicitly allowed by the app.
  • Customization: iOS offers customization options such as changing wallpapers, rearranging app icons, and organizing widgets on the home screen. However, the level of customization is more limited compared to other operating systems.
  • Security: iOS is known for its strong security measures, including hardware-based encryption, sandboxing of apps, and strict app review processes. It provides automatic security updates and features like Find My iPhone for device tracking and remote wiping.
  • Compatibility: iOS is exclusive to Apple mobile devices and has high compatibility with a wide range of Apple hardware. However, it has limitations in terms of compatibility with non-Apple devices and software.
  • Optimization: iOS is optimized for performance and power efficiency. Apple focuses on hardware-software integration to ensure smooth operation and offers features like low power mode and background app refresh settings for optimization.


  • Features: Android is a popular mobile operating system developed by Google. It offers a wide range of devices from different manufacturers, a vast app ecosystem through Google Play Store, customization options, and features like Google Assistant and Google Drive integration.
  • Installation: Android is pre-installed on devices from various manufacturers. Updates are provided by the device manufacturer or carrier, and users can install them over the air.
  • File Structure: Android, being a mobile operating system based on Linux, shares a similar file structure. The file system used in Android is typically ext4. Android devices often have a root directory (/), which contains various system directories and files. Apps and user data are stored in specific directories, and file paths follow the Linux convention with forward slashes (/) to separate directories (e.g., /storage/emulated/0/Documents/File.txt).
  • Customization: Android provides extensive customization options, allowing users to customize home screen layouts, widgets, themes, and system settings. Users can also install alternative launchers and customize app preferences.
  • Security: Android incorporates various security measures, including app sandboxing, Google Play Protect for malware detection, and regular security updates. Users can manage app permissions and utilize features like Find My Device for tracking and remote locking/wiping.
  • Compatibility: Android is an open-source platform available on a wide range of devices from different manufacturers. It offers compatibility with various hardware configurations and has a vast app ecosystem.
  • Optimization: Android includes optimization features such as battery-saving modes, performance monitoring, and storage management tools. Users can optimize system settings, control background processes, and clear cache data.

Up Next

With a foundational understanding of hardware and operating systems, we delve into the very basics of algorithms in the next step. Algorithms are the heart of efficient and effective programming, guiding us in solving problems and optimizing processes.