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 programs would be useless. The picture to the right is an example of Microsoft Windows XP, a popular 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:
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:
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:
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:
Multithreading - Operating systems that allow different parts of a software program to run concurrently. Examples of operating systems that would fall into this category are:
Common questions and answers pertaining to operating systems in general can be found in the operating system question and answers section below. All other questions relating to an operating system in particular can be found through its corresponding operating system page link in the box below.
Operating System listing
Below is a listing of many of the different operating systems available today, the dates they were released, the platforms they have been developed for, and who developed them.
Common operating system questions and answers
- Full listing of all terms relating to computer operating systems.
- How do I determine what operating system I'm using?
- Missing operating system.
- Linux vs. Windows
- Command line vs. GUI.
- Dual booting information.
- See our operating system definition for further information and related links.