What is OS

An operating system or OS is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer operating system, a computer and software programs would be useless. When computers were first introduced, the user interacted with them using a command line interface, which required commands. Today, almost every computer is using a GUI (Graphical User Interface) operating system that is much easier to use and operate.

In other words an operating system or OS is software installed on a computer's the hard drive that enables computer hardware to communicate with and run computer programs. Without an operating system, a computer and software would be useless. In the picture is an example of Microsoft Windows XP, an early popular operating system and Windows 10 would be the latest operating system.

Win-XP

Win 10

Examples of computer operating systems:

Microsoft Windows 10 - PC and IBM compatible operating system. Microsoft Windows is the most common and used operating system.

Apple macOS - Apple Mac operating system. Today, the only Apple computer operating system is macOS.

Ubuntu Linux - A popular variant of Linux used with PC and IBM compatible computers.

Google Android - Operating system used with Android compatible phones and tablets.

iOS - Operating system used with the Apple iPhone and iPads.

Chromium - Google operating system used with Chromebooks.

OxygenOS - OnePlus proprietary operating system.

Operating system types:

  As computers have progressed and developed, so have their operating systems. Below is a basic list of the categories of operating systems and a few examples of operating systems that fall into each of these categories. Many computer operating systems will fall into more than one of the below types.

GUI - Short for Graphical User Interface, a GUI operating system contains graphics and icons and is commonly navigated by using a computer mouse. See the GUI definition for further information. Examples of GUI operating systems are:

System 7.x

Windows 98

Windows CE

Multi-user - A multi-user operating system allows for multiple users to use the same computer at the same time and different times. See the multi-user definition for a complete definition. Examples of operating systems that would fall into this category are:

Linux

Unix

Windows 2000

Multiprocessing - An operating system capable of supporting and utilizing more than one computer processor. Examples of operating systems that would fall into this category are:

Linux

Unix

Windows XP

Multitasking - An operating system that is capable of allowing multiple software processes to run at the same time. Examples of operating systems that would fall into this category are:

Linux

Unix

Windows 8

Multithreading - Operating systems that allow different parts of a program to run concurrently. Examples of operating systems that would fall into this category are:

Linux

Unix

Windows XP