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.
In the picture to the right, is an example of Microsoft
Windows XP, a popular operating system and what the box may look like if you were to visit a local retail store to purchase it.
Examples of computer operating systems
Microsoft Windows 7 - PC and IBM compatible operating system.
Microsoft Windows is the most commonly found and used operating system.
Apple MacOS - Apple computer operating system. The only Apple
computer operating system.
Ubuntu Linux - A popular variant of
Linux used with PC and IBM compatible
computers.
Google Android - operating system used with
Android compatible phones.
iOS -
Operating system used with the Apple iPhone.
The Operating System's Job
You've probably heard the phrase
boot your computer, but do you know what that means?
Booting
is the process that occurs when you press the power button to turn your
computer on. During this process (which may take a minute or two), the
computer does several things:
- It runs tests to make sure everything is working correctly.
- It checks for new hardware.
- It then starts up the operating system.
Windows 7 start up screen
Once the operating system has started up, it
manages all of the software and hardware on the computer. Most of the time, there are many different programs running at the same time, and they all need to access your computer's
Central Processing Unit (CPU),
memory, and
storage.
The operating system coordinates all of this to make sure that each
program gets what it needs. Without the operating system, the software
wouldn't even be able to talk to the hardware, and the computer would be
useless.
Modern operating systems use a
Graphical User Interface, or
GUI (pronounced "gooey"). A GUI lets you use your mouse to click on
icons,
buttons, and
menus, and everything is clearly displayed on the screen using a combination of
graphics and
text.
Each operating system's GUI has a different look and feel, so if you
switch to a different operating system it may seem unfamiliar at first.
However, modern operating systems are designed to be
easy to use, and most of the basic principles are the same.
Before GUIs, computers had a command-line interface, which meant the user had to type every single command to the computer, and the computer would only display text.