From the 26th Of October 2018 Computer Repair 4U will no longer be operating. Many thanks to all of my customers over the past 8 years for your support.

what is an operating system

It is surprising the number of times in my line of work that I have been asked by a customer what is an operating system when I have refereed to it when chatting so I decided a short post on it would help to answer this question and give a basic insight into the function of the operating system and the different types of operating systems that are available.

What is an operating system?

The operating system is the most critical and important element of your computer. It manages all the system resources and is the layer that software like Office or games sit on top of. The operating system is also the bridge between you (the user) and the computer hardware, it allows you to communicate with a computer without knowing how to speak a computers language (binary – 0s and 1s)

While a computer can still be used without an operating system it is essentially useless to most computer users as there is no user interface between the hardware and the user. The operating system is a complex set of programs that are designed to manage and control your computer hardware resources and software. This means they can provide services to programs you run on your computer. For example, if you want to run anti-virus software and google chrome at the same time the operating system manages the access to things like the processor, memory and network to ensure both get what they need from the relevant hardware.

The operating system is essentially the middle man between the software on your computer and the physical hardware in the computer. The below conversation is something I wrote many years ago to try to explain to a friend when he asked me one day “Craig what is an operating system give it to me in layman terms” so hopefully it helps.

What is an operating system – The Conversation

Program Pete: Hey Windows I want to run can you sort me out some resources.
Operating system: Sure, what do you need pal?
Program Pete: I could do with a bit of memory, a bit of processing power and some place to store my settings if that’s ok?
Operating system: Let me have a chat with hardware and see what we can do.
Program Pete: Cheers
*Operating system goes to talk to Hardware*
Operating system: Hey hardware how’s it going? Program Pete is at it again “get me this get me that” do you have some free resources?
Hardware: I’m good one of the fans is out but other than that its all good down here. That Pete he never leaves me alone does he. Tell him he can use 100% of the processor if he needs it as nobody else is using it at the minute but if anti-virus Annie comes in and wants to do a scan he must share it with her. Tell him he can have half the memory too and as much storage as he wants within reason. Tell him to stay away from the network he does not need that and I don’t want him messing about with it!
Operating system: Cheers hardware I will let him know and allocate it to him and fill out the paperwork
*Operating system goes back to Program Pete*
Operating system: Right Pete here is what I can do for you but if someone else comes along you are going to have to share the resources.
*Uri USB is plugged in and anti-virus Annie wakes up*
URI and Annie together: Can we please have some resources!!
Operating System: WOW slow down guys there is enough for everyone just give me a second to split it between you! Remember let me know when you are done with the resources so I can de-allocate them.
Program Pete: *sigh* Great now it’s going to take me a Nano second longer to do my task because I must share with those two.

This may seem overly simplistic but it is essentially what happens.

Types of Operating Systems

You may be surprised to know that there are quite a few different types of operating systems. This is by no means an exhaustive list but we will look at some of the more popular operating systems.

Windows operating systemMicrosoft Windows

Microsoft have been around since the early 1980s and although they developed a number of operating systems prior to Windows 95 it was Windows 95 that was their more consumer orientated version. There have been a number of versions of Windows since which can be seen below.

  • Windows 98 – Released in 1998
  • Windows 98 second edition – Released 1999
  • Windows ME – Released 2000
  • Windows XP – Released 2001. Its worth noting that unlike its predecessors Windows XP was around for a number of years before a brand new version was released and developed a lot of version over these years including Home and Pro editions, media center, starter.
  • Windows Vista – Released 2006 to business customers and 2007 to consumers
  • Windows 7 – Released 2009 – 6 editions
  • Windows 8 – Released 2012 – 4 Editions
  • Windows 8.1 – Released 2013 – Released as an update to Windows 8
  • Windows 10– Released 2015


Similar to Microsoft the Mac has had a number of different operating systems over the years with the first been released in 1984 and code named System 1. Again the below list is not a full list of all apple operating systems just the more well know consumer versions.

  • System 7 – released in 1991
  • Mac OS 8 – released in 1997
  • Mac OS 9 – final major version, released in 1999
  • Mac OS X 10.0 – code name “Cheetah”, released in 2001
  • Mac OS X 10.1 – code name “Puma”, released in 2001
  • Mac OS X 10.2 – also marketed as “Jaguar”, released in 2002
  • Mac OS X Panther – version 10.3, released in 2003
  • Mac OS X Tiger – version 10.4, released in 2005
  • Mac OS X Leopard – version 10.5, released in 2007
  • Mac OS X Snow Leopard – version 10.6, released in 2009<l/i>
  • Mac OS X Lion – version 10.7, released in 2011
  • OS X Mountain Lion – version 10.8, released in 2012
  • OS X Mavericks – version 10.9, released in 2013
  • OS X Yosemite – version 10.10, released in 2014
  • OS X El Capitan – version 10.11, released in 2015
  • macOS Sierra – version 10.12, released in 2016


Linux is a little different to our previous two in that Linux is free and open source software meaning you can download and use it without restriction (while this is still true you do get some versions of Linux that you pay for. These usually have advanced features or software pre-installed for you).
Linux was once considered the operating system of the geek if you like as initially it was not very user friendly and there were compatibility issues with programs.

Although there are still compatibility issues and it is still seen by many as the operating system for the techie it is much improved and the user interface is considered by some to be better in appearance and functionality that both Windows and OS making it a serious consideration when looking at operating systems for your computer.

There are many variations of Linux called Linux Distros (Linux distributions) but some of the more popular active distros can be seen below.

  • CentOS – Originally released in 2003
  • Debian – Has been around since 1993
  • Fedora – Released in 2003
  • Knoppix – Released 2000
  • OpenSUSE – Released 2006
  • Slackware – Released 1993
  • Ubuntu – Released 2004 and probably the most popular distro


Android is an operating system developed by Google and is based on a Linux kernel. Android is primarily designed for touch screen devices like smartphones and tablets but can also be found in some televisions. Android was first released in 2008 and there have been numerous versions of android since then as can be seen below.

  • Froyo – Version 2.2 released in 2010
  • Gingerbread – Version 2.3.3+ released 2011
  • Ice Cream Sandwich – Version 4.0 released Dec 2011
  • Jelly Bean – Version 4.1,4.2,4.3 released 2012
  • KitKat – Version 4.4 released 2013
  • Lollipop – Version 5.0,5.1 released 2014
  • Marshmallow – Version 6.0 released 2015
  • Nougat – Version 7.0,7.1 released 2016


IOS is a mobile operating system developed by Apple exclusively for its hardware. The operating is run on their mobile phones and tablets including the iPhone and iPad. Like the others in this article there have been many different versions over the years. Below is a list of current versions that are still active on devices.

  • Version 3.1.3- Released in 2010
  • Version 4.2.1 – Released later in 2010
  • Version 5.1.1 – Released 2012
  • Version 6.1.6 – Released 2014
  • Version 7.1.2 – Released 2014
  • Version 8.4.1 – Released 2015
  • Version 9.3.5 – Released Aug 2016
  • Version 10.1.1 – Released Now 2016 and is the current version at time of writing
  • Version 10.2 – Currently in Beta at time of writing

You can find more information about previous IOS version at

There are other operating system but this list should cover most of the ones you will encounter. So know you know the answer to the question what is an operating system why not look around and learn something else on our site…

What Is An Operating System
Tagged on: