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What is an Operating System (OS)?
An operating system (OS) is software that enables users to run other applications on a computing device. The computer operating system acts as the interface between the hardware and software, managing system resources for the execution of installed programs. It is the backbone of any computing device, whether a desktop, laptop, or mobile phone.
The OS is primarily responsible for:
- Input devices (keyboard, mouse, touchpad).
- Output devices (monitors, printers, scanners).
- Network devices (modems, routers, network connections).
- Storage devices (internal and external drives).
A key function is to allocate system resources like memory, CPU, and storage for programs. For example, if multiple programs such as a web browser, antivirus software, and a word processor run simultaneously, how the operating system works is to ensure each receives the necessary resources to run smoothly, without becoming unresponsive. It uses techniques like multitasking, multiprocessing, and multithreading to manage these processes.
Operating systems also provide advanced capabilities, such as allowing multiple individuals to use the same device with separate settings and permissions. The concept of an operating system also includes handling complex tasks like networking and security, and providing services to manage data integrity and system stability.
Key Takeaways
- An operating system is software that enables users to run applications on a computing device.
- It handles input, output, network connections, storage, resource allocation, and more.
- Applications can interact directly with hardware, but most are designed for an OS.
- Early systems in the 1940s-1950s had no operating system.
- Modern OSs include Windows 11, macOS, Linux, Android, and iOS.
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Operating System Generations
Early systems in the 1940s-1950s had no operating systems. Over the last 80 years, technology advancements have led to OSs with graphical interfaces, networking, and mobile support.
Below is a brief timeline of the five generations of operating systems.
First Generation – No operating systems (1940s-1950s)
On early computers, programs were input directly using punch cards (e.g., ENIAC).Second Generation – Batch processing systems (1950s-1960s)
Simple OSs processed jobs sequentially without user interaction, using punch cards. (e.g., IBM 7094).Third Generation – Multiprogramming and time-sharing (1960s-1970s)
Multiprogramming allowed multiple jobs in memory, while time-sharing enabled multiple users to interact simultaneously (e.g., UNIX).Fourth Generation – Personal computers and GUIs (1970s-1980s)
OSs with graphical interfaces, multi-tasking, and multi-user functions (e.g., MS-DOS, Windows 1.0).Fifth Generation – Modern operating systems (1980s-Present)
Operating System Functions
The operating system software manages a computer’s applications and hardware.
OS functions include:
- File and device control
- Input/output handling
- Resource allocation
- Security and access
- User interface
What is an Operating System Used For?
While it is possible for an application to interface directly with hardware, the vast majority are written for an OS. What is the use of operating systems? It allows applications to use common libraries, eliminating the need to manage hardware details.
In this way, the OS acts as a comprehensive framework, enabling all applications to interact with hardware consistently, simplifying the development process.
Operating System Examples
Examples of operating systems include:
- Chrome OS (operating system for Chromebooks, Chromium OS open source version).
- MacOS (Formerly known as Mac OS X, including macOS and iPadOS).
- Microsoft Windows (including Windows 11 and Windows Server), .
- Linux (distributions include Debian, Fedora, Ubuntu, and others).
- Unix (BSD, FreeBSD, OpenBSD, and other Unix-based OSs).
- Mobile operating systems (Android, iOS, HarmonyOS, and others).
Operating System Components
Three of the main components of an operating system include:
Other operating system components include device drivers, the file system, the interrupt handler, system utilities, and more.
Types of Operating Systems
Operating Systems for Mobile Devices
Mobile devices – such as smartphones and tablets – require a mobile operating system. The use of the operating system in mobile devices manages functions like touch-based inputs and power efficiency.
Common mobile OSs include:
- Android
- Apple iOS
- HarmonyOS
- KaiOS
- Tizen
According to Statcounter, Android holds the largest share of the global mobile OS market at 71.85%, with Apple iOS at 27.6%. However, iOS has the highest market share in specific countries, including the US, Japan, and Canada.
Like computer systems, mobile devices are vulnerable to threats such as viruses and malicious apps. While mobile OSs have built-in security, additional apps provide platform-specific security features. For example, Android antivirus apps differ from those for iOS due to the unique functions of each platform.
How to Choose an Operating System?
When choosing an OS, consider specific uses of the operating system and how it aligns with expected usage.
Key characteristics of the operating system to evaluate include:
- Availability of software applications
- Compatibility with existing hardware
- Market availability
- Regular software updates
- Security features
- Support for future hardware upgrades
- User interface (command line, GUI, or menu-driven)
The Bottom Line
The operating system definition describes software that allows applications to run on computing devices by managing resources like memory, storage, and input/output devices. The use of the operating system simplifies development and ensures hardware compatibility.
Modern types of operating systems for computers and laptops include Chrome OS, macOS, Microsoft Windows, and Linux or Unix-based OSs. Android and iOS are the leading mobile OSs.
When choosing an OS, consider factors such as software availability, security features, and hardware compatibility.
FAQs
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References
- CHM Decodes Technology for Everyone (Computer History)
- Mobile Operating System Market Share Worldwide | Statcounter Global Stats (GS Statcounter)
