On your computer, laptop, tablet or smartphone, the operating system is the most important piece of software. But what are its responsibilities? What does it actually do?
Perhaps the most famous operating systems in the world are the famous Windows operating systems that run on the majority of laptops and desktop computers, currently at Windows 10.
And then there is the Apple OS X series of operating systems that run on Macs, each named after big cats or California landmarks. You have the famous Android operating systems like “Jelly Bean” that run on smartphones and tablets, and of course the iOS operating systems that iPhones use. And there are tons more too.
Operating systems are usually pre-loaded onto the device when you buy it. For example a PC usually has the most current version of Windows installed already. A Mac has the most recent version of OS X. An iPhone has the most recent version of iOS. And so on. You can change or upgrade operating systems, providing there are no compatibility issues and you have the technical know-how.
What do operating systems do?
Without an operating system, your device will be useless. This is because operating systems are responsible for practically everything that happens on the device.
The operating system manages the interactions between programs and the hardware inside your device
The programs (apps) running on your device obviously all need to use the hardware inside the device to function. For example a video game on a computer needs to use the computers graphics card. Your music player needs to interact with the sound card. And all the programs running on your device will need both the processor (CPU) which will provide the processing power for these programs to function, and access to the device’s internal memory.
The operating system manages this. It allows these programs to interact with the hardware of your device, but also manages all of these interactions so they can happen in the most efficient way possible. If you have multiple programs running at a single time, the operating system manages what resources each program can have, when they can have them, and how much they can have.
The operating system manages the input and output to and from your hardware
A video game needs to send information to a monitor. Your music player needs to send information to your speakers. Skype needs to send information to your webcam. A word processor needs to send information to your printer. This is output.
Also your computer needs a way of understanding what your computer mouse is doing. The same with a keyboard. The same with a stylus pen on a tablet screen. This is input.
The operating system handles all the different ways your computer outputs information to hardware and receives information from hardware. Without an operating system, your computer won’t know how to interact with any of the hardware attached to it.
The operating system provides a way of allowing you to interact with your device and other programs
Your device wouldn’t be of much use if you couldn’t interact with it! As we mentioned above, the operating system manages the interaction between the programs on your device and the hardware inside. But it also needs a way for you – the user – to interact with the programs.
Nearly every modern operating system does this graphically. Buttons, menus, taskbars, desktops and windows. All of this is called a graphical user interface, or GUI (gooey) for short. The GUI is what the operating system “looks like”, from your perspective.
The GUI will allow to you search for and open programs. It allows you to check or test the hardware on your device or change any number of settings that will affect the functioning of your device.
The GUI is also responsible for providing you with feedback, for example if things go wrong, giving you an appropriate error message.
Not all operating systems used a graphical interface by the way. Some of the earlier operating systems, like DOS, were called command line operating systems. There were no buttons, menus or even a mouse with these. Everything you wanted to do had to be typed into the computer on a “command line”.
Saving, storing and retrieving files that you created is obviously important. These are saved on the hard disk drive inside the device and the operating system handles this through a file management system.
The operating system allows your computer to join a network of other computers and oversees interaction across this network, so you can, for example, see and interact with other devices and share files or folders across the network. It also allows programs to interact with the networking hardware inside the device as we pointed out above in the first point.
Keeping everything stable and working!
Perhaps one of the most important jobs of the operating system is the thankless task of keeping everything stable and working! When it comes to hardware and software, most of which are made by different companies in different parts of the world, there will be issues. Compatibility errors, coding glitches, syntax errors, logical errors. The list goes on.
The operating system needs to be able to handle these problems in a way that doesn’t just result in your device freezing (though as most of us know, if often does any way!) The best operating systems out there are the most stable ones, and it is one of the hardest jobs to get right.