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What is an Operating System (OS)?

What is an Operating System (OS)?

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Operating systems play a crucial role in our digital experiences. Our idea is to give you a detailed description and a historical exploration of how OS evolved with its different generations. Go through the reasons behind the importance of operating systems, explore their diverse types, and gain insights into their workings. 

If you are also looking for some well-known OS choices and want expert guidance on choosing the one that suits your needs, we also have that answer for you below! Let’s explore.

Define Operating System

An operating system is essential software that manages computer hardware and software resources. It is a crucial intermediary between users and the computer’s hardware components. 

Following its initial loading through a boot program, the operating system efficiently manages all application programs, ensuring seamless interaction and resource allocation, thereby enabling the computer to function smoothly.

History of Operating Systems

The history of operating systems can be divided into several generations, each representing a significant advancement in the field. Let’s explore each generation in the following ways:

  • First Generation (1940s-1950s):
    The first generation of operating systems emerged alongside early electronic computers. During this period, computers were primarily used for scientific and military purposes. Operating systems were rudimentary, primarily focusing on managing input and output operations. A notable example of this generation is the Electronic Numerical Integrator and Computer (ENIAC), one of the earliest electronic general-purpose computers.
  • Second Generation (1950s-1960s):
    The second generation witnessed significant advancements in operating systems with the introduction of batch processing. This concept allowed multiple jobs to be collected and executed in sequence, improving the efficiency of computer utilization. Operating systems like IBM OS/360 and Burroughs MCP (Master Control Program) were developed to support batch processing. Additionally, multiprogramming facilitated the concurrent execution of multiple programs, further enhancing efficiency.
  • Third Generation (1960s-1970s):
    The third generation marked a pivotal era with the introduction of time-sharing systems. Time-sharing enabled multiple users to interact with a computer simultaneously, each running their own processes. Unix, developed at Bell Labs, was a significant operating system for this generation. Unix introduced critical concepts such as hierarchical file systems, command-line interfaces, and inter-process communication, which laid the foundation for future operating systems.
  • Fourth Generation (1980s-Present):
    The fourth generation witnessed the rise of personal computers and Graphical User Interfaces (GUIs). Operating systems like Microsoft’s MS-DOS and Apple’s Macintosh System were crucial in popularizing personal computing. Graphical user interfaces replaced command-line interfaces, providing a more user-friendly experience. Introducing windowing systems, such as Microsoft Windows and Apple’s Mac OS, allowed multitasking and the execution of graphical applications, further enhancing usability.

Why is the Operating System Important?

The operating system is a crucial software that powers the computer. It manages the computer’s memory, processes, software, and hardware. It also allows users to interact with the computer without understanding its technical language. 

Operating systems are important for several reasons, and we have highlighted these in the following:

  • User Interaction- An OS provides an easy-to-use interface that lets people communicate with the computer effortlessly. It enables tasks like starting programs, organizing files, and other essential functions, making computing accessible to many users.
  • Resource Management- Operating systems efficiently handle a computer’s hardware resources, including the CPU, memory, storage, and peripherals. This optimization ensures that resources are used wisely, preventing waste and improving system performance. It ensures that multiple programs can run at the same time without problems.
  • Security- OSs have strong security features that protect the computer from unauthorized access and harmful software. They use methods like passwords, encryption, and access control to keep sensitive information safe and the system working correctly.
  • Hardware Abstraction- Operating systems abstract the underlying hardware complexities, enabling software developers to create applications without worrying about specific hardware details. This abstraction enables compatibility and simplifies software development.
  • File Management- Operating systems organize and manage files and directories, making it easier for users to store, retrieve, and organize their data efficiently. This systematic approach simplifies data handling.
  • Task Management- OSs handle the execution of processes and multitasking, allowing many programs to run together. This boosts productivity and lets users switch between applications easily.

Types of Operating Systems

  • Batch Operating System
    A Batch Operating System (BOS) is a specialized OS that processes tasks sequentially without direct user interaction. Users submit jobs to the system, which executes them one by one. 

    BOS is ideal for large-scale computing, like scientific simulations and data processing, and ensures efficient resource allocation. This approach streamlines tasks, making it a valuable tool for automating and managing lengthy computational processes, especially in research and data-intensive applications.

    Examples of batch operating systems include payroll systems, billing systems, bank Statements, etc.
  • Multiprogramming Operating System
    A multiprogramming operating system is a type of operating system that enables the concurrent execution of multiple programs. In a multiprogramming environment, the OS allocates time to each program, switching between them swiftly.

    This facilitates efficient resource utilization and responsiveness, making it well-suited for interactive tasks like word processing and web browsing. By managing multiple jobs simultaneously, it optimizes resource utilization, providing users with a seamless computing experience.

    Examples of multiprogramming operating systems include Google Chrome, MS Excel, and Firefox browser.
  • Time-Sharing Operating System
    A time-sharing operating system allows multiple users to share a computer simultaneously. It divides the computer’s resources into small portions, ensuring users can run their programs separately. This is possible because the operating system allocates time to each user and frequently switches between them. 

    Time-sharing operating systems are commonly used on mainframes and server computers. They are more intricate than multiprogrammed systems as they support multiple users interacting with the computer simultaneously. It adds complexity and versatility to the system.

    Examples of time sharing operating systems include Unix, Linux, and Windows Server.
  • Distributed Operating System
    A distributed operating system is a unique software engineered to function across a network of independent, physically separate computers. In this setup, the operating system is decentralized, with each computer in the network tasked with executing a distinct part of the operating system’s functions. These systems are commonly used in extensive computing techniques like cloud computing and grid computing. 

    The various examples of distributed operating systems include Amoeba, Plan 9, and LOCUS. 
  • Network Operating System
    A network operating system is an operating system designed to facilitate the management of interconnected computers within a local area network (LAN). These systems are customized to support workstations, PCs, and occasionally older terminals on the same network. 

    This type of operating system is specifically designed to oversee the management of a network of interconnected computers. They offer essential services like file sharing, printing, and security, making them ideal for small businesses and home networks. 

    Examples of network operating systems are UNIX, Linux, Microsoft Windows Server 2008, and Microsoft Windows Server 2003.
  • Real-Time Operating System
    A real-time operating system is a specialized type of operating system known for its predictability and deterministic behavior. In this OS, tasks are executed with precise timing, ensuring that critical operations respond promptly to events. 

    This level of reliability and timeliness is essential in applications such as industrial control systems and medical devices, where consistent, rapid responses are imperative.

    Real-time operating systems examples include airline traffic control systems, Command Control Systems, airline reservation systems, etc.
  • Mobile Operating System
    A mobile operating system is a specialized software that enables smartphones, tablets, and similar devices to execute applications and functions. Serving as an intermediary between the device’s hardware components and its software capabilities, a mobile OS is specifically designed for mobile devices like smartphones and tablets. 

    These operating systems offer touchscreen interfaces, robust app support, and efficient battery management, optimizing the user experience on portable devices by seamlessly coordinating hardware and software functionalities.

    Examples of mobile operating systems are Android, iOS, Windows, etc.
  • Embedded Operating System
    An embedded operating system is a specialized software designed for dedicated devices like microwave ovens and car engine control systems. The core function of an embedded OS is to efficiently execute the code required for these devices to fulfill their intended functions. 

    These operating systems are characterized by their compactness, efficiency, and ability to run on limited hardware resources. They ensure reliable operation in devices where precision and reliability are essential, despite the constraints of hardware limitations.

    Some examples of embedded operating systems are AUTOSAR, VxWorks, QNX, Linux, Android, etc.

Components of Operating Systems

There are various components of operating systems, which are listed below:

  • Process Management
    Process management oversees processes’ creation, scheduling, and administration, representing active program instances. 

    Its responsibilities include:
    • Allocating resources, including CPU time, memory, and I/O devices, to processes
    • Prioritizing tasks to ensure the execution of critical processes first
    • Optimizing resource utilization by suspending and resuming processes
    • Termination of processes that are redundant or causing issues
  • File Management
    File management is responsible for organizing, storing, and retrieving files and directories on storage devices. 

    Its main functions are:
    • Ensuring efficient allocation of storage space for files and directories
    • Implementing access controls to safeguard data from unauthorized access or modification
    • Facilitating file searching and retrieval that makes data easily accessible to users.
    • Managing file and directory metadata, including attributes and permissions
  • Command Interpreter (Shell)
    The command interpreter, also called the shell, serves as the user’s interface to interact with the operating system through text-based commands. 

    It has the following responsibilities, including:
    • Parsing and interpreting user-entered commands, converting them into executable instructions
    • Managing script execution and automating repetitive tasks through scripting languages
    • Providing feedback and responses to user queries, enhancing user-friendliness
  • System Calls
    System calls act as a crucial bridge between application software and the operating system, enabling applications to request services from the OS.

    Its main functions are:
    • Allowing applications to access and utilize hardware resources, such as reading from and writing to files
    • Providing a standardized interface for diverse software to interact with OS
    • Handling processes, file operations, and communication between processes
  • Signals
    Signals are notifications dispatched to processes by the operating system or other processes to signify events, such as interrupts, errors, or termination requests. 

    Their functions include:
    • Signaling exceptional conditions or events to processes for immediate attention
    • Enabling inter-process communication and synchronization
    • Handling critical events gracefully to prevent system instability
  • Network Management
    Network management involves configuring, monitoring, and optimizing computer networks. 

    It has the following responsibilities:
    • Setting up network connections, including IP addressing, routing, and firewall configurations
    • Ensuring network security by implementing protocols, authentication, and encryption
    • Monitoring network performance, diagnosing issues, and facilitating network troubleshooting
    • Supporting efficient data transfer and communication over local and wide-area networks
  • Security Management
    Security management is dedicated to safeguarding the operating system and its data against unauthorized access, threats, and vulnerabilities. 

    Its essential functions include:
    • Implementing user authentication mechanisms to validate user identities
    • Executing access control policies to restrict user permissions and data access
    • Employing encryption and security protocols to protect sensitive data
    • Detecting and mitigating security threats, such as malware and intrusions
  • I/O Device Management
    I/O device management manages the interaction between the operating system and peripheral devices like keyboards, mice, printers, and network adapters. 

    Its main responsibilities are:
    • Managing data transfer between the CPU and I/O devices efficiently
    • Ensuring proper functioning and synchronization of input and output devices
    • Providing a standardized interface for software applications to access and utilize hardware peripherals
  • Secondary Storage Management
    Secondary storage management deals with the organization and management of storage devices, such as hard drives and solid-state drives. 

    Its core tasks include:
    • Formatting storage devices for data storage and retrieval
    • Organizing files and directories efficiently on storage media
    • Managing available free space and ensuring data backup and recovery mechanisms are in place
  • Main Memory Management
    Main memory management allocates, tracks, and optimizes memory resources for processes.

    Its main responsibilities are:
    • Allocating memory space to processes as needed for execution
    • Efficiently manage available memory to prevent resource shortages
    • Implementing memory protection mechanisms to ensure process isolation and data integrity
    • Reclaiming memory from terminated processes for reuse

How do Operating Systems Work?

Below, we have given a simplified overview of how operating systems work. 

  • User Interfaces with the System & Application Software:
    • Users interact with software applications (e.g., word processors, web browsers, and games) and the overall system through user interfaces. These interfaces can be graphical (GUI) or text-based (CLI).
  • System & Application Software Interfaces with the Operating System:
    • Software applications and system software, including drivers and utility programs, rely on the services and resources provided by the operating system.
    • Application software communicates with the operating system to perform tasks like file operations, network connections, and hardware interactions.
  • Operating System Interfaces with the Hardware:
    • The operating system acts as an intermediary between software and hardware. It manages and abstracts the underlying hardware components, including the CPU (central processing unit), RAM (random-access memory), and I/O (input/output) devices (e.g., storage drives, printers, and graphics cards).
    • When an application or system software needs to perform a hardware-related task (e.g., reading data from a hard drive or printing a document), it makes requests to the operating system, which in turn manages the hardware resources to fulfill those requests.

This interaction ensures that software applications can run on various hardware configurations without knowing each system’s specific details. The operating system provides a standardized interface to the hardware, making it easier for software developers to create applications that work across different computers and devices.

Several popular operating systems are widely used and designed to meet various user needs and preferences. These popular operating systems include:

  • Windows- With over 1 billion users worldwide, Windows is the top desktop operating system. It offers a wide range of features and software, from the versatile Office suite to gaming and productivity tools.
  • macOS- macOS powers Apple’s Mac computers, known for its stylish and easy-to-use interface. Renowned for its intuitive interface, macOS seamlessly integrates with Apple’s hardware and software ecosystem, providing a streamlined user experience. 
  • Linux- Linux is an open-source and customizable operating system embraced by developers, businesses, and individuals. It’s free and can be adjusted to fit specific requirements.
  • iOS-Apple’s mobile devices, including iPhones and iPads, rely on the iOS mobile operating system. Known for its intuitive design and seamless app experience, iOS has earned a loyal following among users looking for a streamlined and secure mobile operating system.
  • Android- Android, used by over 2.6 billion people globally, is the most popular mobile operating system. It’s known for being open-source, customizable, and compatible with various devices.

How to Choose the Right Operating System

Selecting the ideal operating system for your computing needs requires careful consideration. Start by defining your computer’s primary purpose, whether for daily tasks, gaming, creativity, or professional use. You must ensure compatibility with your hardware, like the CPU, RAM, and graphics; and evaluate software compatibility for essential applications. 

Also, decide between a graphical user interface (GUI) like Windows or macOS and a command-line interface (CLI) like Linux, based on your comfort level and customization needs. Consider ecosystem integration, security features, gaming preferences, budget, and community support. So, choose wisely, as choosing an operating system can significantly impact your digital experience.

Conclusion

Operating systems are pivotal in modern computing, efficiently managing resources and enhancing user interactions. Understanding operating systems’ definitions, types, and components that we discussed earlier is key to grasping their importance in today’s computing world. 

These systems play a vital role in modern computing, ensuring that using computers is easy and efficient. We can conclude by saying operating systems keep our digital world running smoothly, constantly adapting and improving how we interact with technology.

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About the Author

Senior Consultant Analytics & Data Science

Sahil Mattoo, a Senior Software Engineer at Eli Lilly and Company, is an accomplished professional with 14 years of experience in languages such as Java, Python, and JavaScript. Sahil has a strong foundation in system architecture, database management, and API integration.