Operating System (OS)

What Is an Operating System (OS)?

An operating system (OS) is a software program that manages the resources of a computer, allowing apps to communicate with the computer’s hardware.

Most software programs are not designed to communicate directly with the hardware. Instead, they rely on the operating system to handle hardware communication.

In the early days of computers, operating systems were not available. Each computer program had to include all the necessary code to run, connect with the hardware, and perform its intended function. This made software development complex and operating computers difficult. Furthermore, each software program could only run on the specific computer it was designed for.

Functions of Operating System

Operating systems perform various functions to achieve their goals. These functions include:

Process Management: At any given time, the CPU may have multiple processes in the ready state. However, the CPU can only handle one process at a time. Therefore, the operating system must implement procedures to ensure that all processes have fair and continuous access to resources. Different CPU scheduling techniques, such as first come, first serve, round-robin, shortest job first, and priority scheduling, are used to manage processes.

Memory Management: When running a process, the entire process is loaded into the main memory and executed. Once the process is completed, the memory is released and can be used for other processes. It is the responsibility of the operating system to manage memory by allocating and deallocating memory for processes.

I/O Device Management: A system has various I/O devices, and different processes require access to different resources. However, processes should not directly access these devices. The operating system authorizes the usage of I/O devices by the processes that need them.

File Management: Each computer has its own set of files, folders, and directory structure, which are managed by the operating system. A File Allocation Table (FAT) is used to keep track of file information, such as filename, size, and type. The operating system also ensures that files are not accessed by unauthorized users.

Virtual Memory: When the size of an application exceeds the main memory, the operating system is responsible for loading frequently used pages into the main memory. This is known as virtual memory.

What Are the Most Popular Operating Systems?

Throughout the history of computing, several operating systems have gained popularity. Some examples include:

Microsoft Windows: Microsoft Windows is the most widely used operating system on computers today. The latest version is Windows 10, and it runs on PC and IBM-compatible systems.

macOS: macOS is Apple’s core operating system, used on desktop and laptop computers.

Linux: Linux is a free and open-source operating system that can be installed on PCs and IBM-compatible systems. It has various distributions, such as Ubuntu, Debian, Red Hat, and Slackware.

Chrome OS/Chromium: Chrome OS is the pre-installed operating system on Google Chromebooks.

Operating Systems for Mobile Devices

A mobile operating system, also known as a portable operating system, is used on smartphones and tablets.

Android: Android is a mobile operating system that runs on smartphones and tablets. It is currently the most common operating system worldwide.

iOS: iOS is the operating system that runs on Apple’s iPhones and iPads.