What Is
an Operating System?

What is an operating system? It depends on who's asking the question and how experienced they are with computers.

For a computer novice, an operating system is just a name -- Linux, Macintosh, or Microsoft Windows.

Building on the work of others.

Let's look at operating systems from the point of view of a computer programmer. Operating systems make it easy for programmers. The presence of an operating system lets the programmer start working without having to start from scratch.

The presence of an operating system means a lot of the grunt work of programming has already been done for you. How much programming? Well, it takes 1,000 or more person-years of human labor to create an operating system.

How much labor is 1,000 person-years? It is 1 person laboring 40 hours a week for 1,000 years. Or it is 5 people laboring 40 hours a week for 200 years. Or more reasonably, it is 200 people laboring 40 hours a week for 5 years.

Yes, commercial operating systems require that much labor to create -- and more. What are people doing that requires so much labor? They are creating software that does a lot a little things -- little things that our programmer is going to need if he is to create a useful program.

Our programmer needs to keep track of the date -- the operating system keeps track of the date. Our programmer needs to be able to talk to the hard drive -- the operating system does all the reading and writing to the hard drive for him. Our programmer is writing a program that will talk to another program on another computer across the Internet -- the operating system is able to talk to any other computer on the Internet.

In a nutshell, an operating system allows a computer programmer to build on the work of other computer programmers. The makes our computer programmer a very powerful person because he doesn't have to reinvent the entire history of computer science all by himself each time he does a new program.

Operating Systems
Make Programmers Powerful

Is it possible to do useful work without an operating system? Yes, Some programmers do exactly that.

I've worked for medical device manufactures where the device is a computer with no operating system. Believe me, its hard work building such a device from the ground up.

Computers that are without operating systems are very primitive. It takes many people many person-hours to build up the capability of such a primitive machine to the point where it will perform even the simplest of tasks.

You Depend on
Your Operating System

Your operating system is the primary ingredient in a reliable computer. When your computer crashes, it is your operating system that crashed. This is true regardless of how artfully written the error message is that blames it on the guest program.

Guest computer programs do not crash computers. Only operating systems can do that. If your operating system tells you that your program has created a protection fault, that has crashed your entire computer, don't believe it. Why? Because it takes access to privileged instructions to create a protection fault and your operating system is the only program on your system that has such privileges.

People Love
Their Operating Systems

No piece of software makes people more passionate than their operating system. They will defend their operating system like their religion.

Linux users love their operating system because of the freedom it gives them. It's one of the most powerful operating systems out there, it's free to install, and it's just full of utilities.

Windows users love their operating system because of its simplicity and universality. It's simple because it's user interface is very dumb -- which is not such a bad idea. The smarter the interface, the longer it takes to learn it. The dumber the interface, the easier it is to become proficient with that interface.

The universality of Windows is based on its overwhelming market share. Because of this universality, it is easy to get the latest peripheral that you just bought for your computer working with Windows.

Macintosh users love its integration. Everything works well with everything else just out of the box.

Both Linux users and Macintosh users feel sorry for Windows users when it comes to system crashes. Linux systems can stay up and running for years and never crash. Both systems have a reputation for reliability.

Learning More
About Your Operating System

Probably the best way to learn more about your operating system is to buy a book on it. Do a search on Amazon using the name of your favorite operating system (Linux or Macintosh or Windows) as a search argument.

Be careful! Books that are advanced are often given negative reviews by beginners and books that are too easy are often given negative reviews by people who are experts in the topics. Be sure to make a judgment as to where the reviewer is coming from before taking the review too seriously.

The More You Know . . .

The more you know about your operating system, the easier it is to navigate your computer. Even a little bit of knowledge can go a long way.

©Edward Abbott, 2002. All rights reserved. Revised November 13, 2002.

Questions or comments? Email me at ed@WebSiteRepairGuy.com.

Directory of Operating System Resources

The Operating System as Intermediary Between You and Your Hardware

The Operating System as a Group of Programs