Computer Operating Systems

The operating system on a computer is the software which starts when the computer is switched on and which controls the operation of all other software that is subsequently run on the computer.

There are two main operating systems:

Windows

Windows is what most people use. It is designed to make it easy to use application programs written by other people and to hide most of the details of the computer hardware. In theory it should make the computer look like something that most people are familair with, namely an office desk and filing system.

It was not designed to make it easy for people, particularly people who aren't Windows specialists, to write their own programs.

I have been using computers since 1965. I use a Windows PC when I want to run an existing program. I would never choose to write, develop or test a new program of my own on Windows.

Unix and Linux

Linux has been around since the 1970s. It was designed by computer programmers as an environment for writing new programs. It is very good for this.

Linux is not `user friendly' for those who do not understand how it works. If you have never used Unix before then you certainly cannot just sit down at a Unix computer and get started by clicking on things and seeing what happens. Attaching a new piece of hardware, e.g. a USB device, to a Linux PC can be a serious challenge.

However, Unix is excellent, once you know a bit about it, for the job for which it was designed, i.e. writing programs. Another advantage of Unix is that it is both more secure by design than Windows and has also attracted fewer hackers and virus writers.

I would always choose to write and develop any program on Unix whenever possible. Because of its better security I normally use it for web browsing and email.

Web Browsers and the WWW

Modern web browsers in effect provide an operating system which sits on top of either Unix or Windows. Because the WWW is an open standard which everybody uses (although Microsoft does many things which are nonstandard) it will look the same regardless of what underlying operating system is used.

There are two standard computer languages associated web browsers, Java And JavaScript. Programs written for use in web browsers in either language should (in theory, and to a large extent in practice do) run in any browser on any operating system. (Including Mac OS which I haven't mentioned so far, as it appears to combine the disadvantages of both Unix and Windows and few of the advantages of either.)

Java is a hard language to learn, although very powerful and quite suitable for serious computation.

JavaScript looks a bit like Java, although it is fundamantally different. It is easy to get started with and, if its more esoteric aspects are mastered, very flexible. Because of the way it works it is unsuitable for major computation, but on a fast modern machine, capable of handling most `amateur' problems.