| Introduction to OS |
| If you have a computer, then you have heard about operating systems. Any desktop or laptop PC that you buy normally comes pre-loaded with Windows XP. Macintosh computers come pre-loaded with OS X. Many corporate servers use the Linux or UNIX operating systems. The operating system (OS) is the first thing loaded onto the computer — without the operating system, a computer is useless. |
| More recently, operating systems have started to pop up in smaller computers as well. If you like to tinker with electronic devices, you are probably pleased that operating systems can now be found on many of the devices we use every day, from cell phones to wireless access points. The computers used in these little devices have gotten so powerful that they can now actually run an operating system and applications. The computer in a typical modern cell phone is now more powerful than a desktop computer from 20 years ago, so this progression makes sense and is a natural development. In any device that has an operating system, there’s usually a way to make changes to how the device works. This is far from a happy accident; one of the reasons operating systems are made out of portable code rather than permanent physical circuits is so that they can be changed or modified without having to scrap the whole device. |
| For a desktop computer user, this means you can add a new security update, system patch, new application or often even a new operating system entirely rather than junk your computer and start again with a new one when you need to make a change. As long as you understand how an operating system works and know how to get at it, you can in many cases change some of the ways it behaves. And, it’s as true of your cell phone as it is of your computer. |
| The purpose of an operating system is to organize and control hardware and software so that the device it lives in behaves in a flexible but predictable way. In this article, we’ll tell you what a piece of software must do to be called an operating system, show you how the operating system in your desktop computer works and give you some examples of how to take control of the other operating systems around you. |