There can't be many people who haven't heard of Linux. In short, it's an operating system just like Windows but, unlike Windows, you won't find it on many PCs you buy from the high street or from computer magazines.

The reason for its popularity is threefold. First, most versions of Linux (of which more later) are free; second, anyone can modify it to suit their needs; and third, it runs well on low-specification computers.

Linux has a reputation as an operating system for high-end purposes such as web servers, and high-end users such as programmers.

It is also seldom out of the news, appearing in devices as diverse as the PlayStation2 and Xbox, and on 60,000 desktop computers in the West Yorkshire police force.

IBM actively promotes Linux to big companies and even Microsoft acknowledges that "Linux is a serious competitor".

So what is Linux exactly, and how does it relate to the average home or office computer user? More importantly, is it as friendly as its penguin mascot suggests?

In this feature, we'll be reporting on the background and history of Linux, and showing you how it looks and works. If you fancy having a go, we'll also be telling you how to get it and install it, and how to find your way around it.

The ins and outs
The Linux story starts in the early 1970s when AT&T's Bell Labs developed an operating system called Unix for the mainframe computers of that era.

Unix rapidly became an industry standard, with companies such as Sun Microsystems and DEC writing their own versions.

In 1983, Richard Stallman, a programmer at the Massachusetts Institute of Technology, founded the GNU project. This stood for 'Gnu's Not Unix' and his aim was to combat the increasingly commercialised versions of Unix with a freely available version created by volunteers and enthusiasts from around the world.

The terms of the Gnu Public Licence (GPL) ensured that, unlike commercially produced software, GNU would be open to inspection, modification and improvement by anyone and everyone.

By 1991, thanks to the personal computer's popularity, computing was no longer the prerogative of big businesses and academic institutions.

This prompted a Finnish student, Linus Torvalds, to embark on creating a version of Unix that would run on a standard PC rather than a costly mainframe computer.

Thus was born 'Linux', named after its creator but also following the GNU tradition of wordplay. The name also stands for 'Linux Is Not UniX'

Torvalds' principal achievement was the creation of a 'kernel', the core of an operating system which is responsible for making all the parts of a computer work together.

By itself, however, it isn't much use as it doesn't provide any way for a user to interact with it. For that there needs to be something called a 'shell'.

Unix used the 'Bourne' shell; the GNU programmers came up with BASH - the 'Bourne Again SHell'.

While many Linux users are happy with BASH, the fact that it only allows text-based commands to be typed on a keyboard is a bit of a deterrent and so the final piece of the Linux jigsaw is the 'user interface' or UI.

There is range of different Linux UIs available and the best offer the same set of features as Windows. The two leaders in the UI field are GNOME and KDE and we'll be looking at both of these later.

Get it on
So where can you get a copy of Linux? Just because Linux is free, it doesn't mean you can't buy it. Conversely, the GPL doesn't stop companies making money out of Linux by selling copies on CD-Rom.

Such companies often offer added value, such as printed manuals, technical support and training. There are many such distributors, including Red Hat, Mandrake, SuSe, Slackware, Debian, Xandros (formerly Corel Linux) and Lindows.

The various versions of Linux are also known as 'distributions'. At the time of writing, Amazon was offering Red Hat 8 Personal for around £32. This features seven CDs containing the operating system, applications and documentation, as well as a printed manual and 30 days' technical support.

Various other versions can be ordered from the distributors' websites (see below).

You can get other Linux distributions for much less. BuyLinuxNow.co.uk, for instance, offers Mandrake Linux on CD-Rom for just £4.

If you'd rather spend money than effort, then you can buy an entry-level PC with Lindows pre-installed from as little as £250, excluding a monitor.

If you'd like to get Linux free, you can download it from lots of different places. Bear in mind, though, that this will involve a long wait. Even with a broadband connection, downloading a 600MB file can take a good few hours.

If you can't manage the download, there is still a solution. Unlike Windows, you're free to install most versions of Linux on more than one PC so it's perfectly legal to borrow a disc from a friend.

Separate lives
So you've got a Linux installation disc, now what? First, you need to make room for it on your hard disk and, once again, there's a trade off between effort and expense.

Assuming you want to retain Windows on your PC, the simplest thing would be to buy a new hard disk, configure this as a 'slave' and install Linux on the new disk.

Alternatively, you can give Linux an existing partition on your hard disk or use the spare space on an existing partition.

This is no trivial matter, as Linux partitions differ from Windows partitions and you need to first back up your existing data and then use the partitioning tool that comes with your copy of Linux.

After that, you need to install a 'boot manager', so that you can choose between starting Linux or Windows when you switch on your PC.

Some versions of Linux come with their own boot manager but it's far simpler to use an application like Partition Magic.

There is, however, a third way, which is especially interesting to those who want to try out Linux before taking such drastic steps: install Linux on a 'virtual' PC.

This has a number of advantages. You don't need to worry about creating special partitions or setting up boot managers, as the whole system is stored as a large file on your computer and runs in a window as just another application within Windows.

First, you need to get hold of the Virtual PC software from Connectix. You can download a fully functional 45-day trial here.

From the same site, go to the Knowledge Database and read the article ID 4614: How to install Linux. You are strongly advised to print this out and follow the instructions closely.

Whichever method you choose to install Linux, one important step is to set up 'users'. You'll be prompted for a password for 'root'. This is the 'super-user' who has the power to do anything, such as install software or change the hardware set-up.

Consequently, it's not a good idea to use the root account for general use, so create one or more users, each with their own password.

RESOURCES

BOOKS
In the beginning was the command line
Neal Stephenson, Avon Books.
A highly entertaining account of operating systems.

Just For Fun: The Story of an Accidental Revolutionary
Linus Torvalds and David Diamond, Texere Publishing.
Torvalds' own story about his life, work and marriage to a six-times karate champion.

Rebel Code
Glyn Moody, Penguin Books.
A fascinating detailed account of the Linux story.

Running Linux 4th edition
Welsh, Dalheimer and Kaufman, O'Reilly.
A standard Linux textbook giving a detailed technical view in readable language.

WEBSITES FOR DOWNLOADS
Although the following sites are often very busy, they usually contain links to localised 'mirror' sites.

www.redhat.com/apps/download

www.linux-mandrake.com/en/ftp.php3

www.suse.com/us/private/download/index.html

ftp.slackware.com/pub/slackware/slackware-8.1-iso

www.debian.org/distrib

www.xandros.com/downloads.html

BUYING LINUX
The sites listed above contain links to direct purchase outlets or national vendors. In addition, the following UK specialists sell various distributions on CD-Rom.

www.buylinuxnow.co.uk/home.htm

www.linuxemporium.co.uk

www.smb-computing.co.uk

GENERAL RESOURCES
beginnerslinux.org - a getting started guide.

www.linux.org - a centre for Linux resources founded in 1994.

www.building-tux.com - an overview of different versions of Linux.

linuxwebring.org - an association of Linux sites.

rhlufaq.synfin.net - Red Hat users' information.

www.linuxquestions.org - a free forum in which to ask experts your Linux questions.

www.linuxlinks.com - a portal to all sorts of Linux resources, including textbooks and jobs.

PARTITION MAGIC
Partitioning a hard disk is not a task for the faint-hearted but thankfully there is an application that simplifies it as much as possible.

PowerQuest Partition Magic (£44) is far more user-friendly than anything Windows or MS-DOS can offer and can also create both Windows and Linux partitions from spare space on your hard disk without destroying any existing data (although you should always back up important data first).

It runs under Windows, rather than from a command prompt, and can shrink, expand and merge existing partitions as well as create new ones.

Partition Magic also comes with BootMagic, a utility designed to let you run multiple operating systems on your PC.

Finally, should you decide not to continue with Linux, Partition Magic provides an easy way to restore your hard disk partitions to all-Windows and remove multiple booting.

Although a trial version is available from www.powerquest.com, this will only let you try out the 'look and feel'. It won't actually make any changes.

INSIDE AND OUT
The Gnome desktop in Red Hat isn't too intimidating for Windows users. By default, you have just three icons on the desktop. The Home icon takes you to your home folder - rather like My Documents in Windows. Each user has their own Home folder and, by default, won't be able to access other users' folders. When a folder is not accessible, you'll see its icon overlaid by a red circle with a diagonal bar.

The Nautilus file manager is very similar to Windows Explorer, with a row of buttons to navigate the file system. Clicking up from the Home folder will take you to the 'root' of the file system, designated by just a forward slash (/).

It's difficult to draw an analogy with Windows here but it's a little like the top level of your hard disk. The C: folder, in other words.

In here you'll find many folders with names such as bin, boot, dev, mnt and so on. The choice of these short names is rooted deep in the annals of Unix and Linux, when all commands and folder names were typed on a keyboard.

Dev, for example, isn't as informative as Device Drivers, which is what it actually contains, but it takes a lot fewer keystrokes.

The Start Here icon opens a window. Here you'll find icons for Applications, Preferences, Server settings and System settings.

Applications show the contents of the start menu, while the last three correspond roughly to the contents of Windows Control Panel.

The Preferences folder contains the settings that are customisable by each user, such as mouse, screensaver and background (wallpaper) settings.

The System and Network folders are for root (administrator) use and, although you can see the contents, you'll have to supply the root password to access any of the items within.

The third icon, Wastebasket, serves the same function as the Windows Recycle Bin.

At the bottom of the screen, the Gnome Panel bears a strong resemblance to the Windows Task Bar. Starting at the left, the Red Hat button functions like the Windows Start Menu.

At the top is a cascading structure of programs and utilities (the same as the contents of the Applications folder in Start Here), and beneath this are commands for searching for files, running programs by typing a name, locking the screen and logging out.

To the right of the Red Hat button is a set of buttons corresponding to Windows Quick Launch. On a standard installation, you have the Mozilla web browser, Ximian email application and three icons for the OpenOffice word processor, spreadsheet and presentation producer.

To the right of these is the Workspace Switcher. By default this gives you four virtual desktops on which to spread out your folders and programs.

If you click on the top-left corner of any window, you'll find you can move it to another workspace and clicking on the corresponding square on the Switcher button jumps to that workspace. It's an excellent alternative to having to dig through piles of overlapping windows.

To the right of the Switcher is a set of buttons showing all the windows open on the current desktop, just as in Windows. To the right of that, there is a small area showing the clock and any utilities that may be installed.

The OpenOffice suite deserves a special mention as, despite being free, it is fully equipped with all the features you would expect in a top-end product.

As well as the word processor, spreadsheet and presentation program, there's a drawing application and a tool for creating mathematical formulae.

The menus and toolbars are broadly similar to those in Microsoft Office and it will open and save files in Microsoft format, such as .doc and .xls files.

If you delve through the Red Hat menu, you'll find lots of other free software, including a variety of games that far exceeds the offerings from Microsoft.

Also worth a mention is the Gnu Image Manipulation Program, a powerful, if somewhat idiosyncratic, image-editing application.

THE OTHER DESKTOP
Most versions of Linux will offer you a choice of desktops, the two principal contenders being Gnome and KDE.

We've covered Gnome in some detail so here's a whistle-stop tour of KDE. Although it's somewhat more cluttered than Gnome, the principles are pretty much the same.

A few extra desktop icons connect to various websites and the Konqueror can be used to browse both local files and the web.

The panel at the bottom of the screen, known as Kicker, again sports an application Start button and shortcuts to the web browser, home folder, documentation and so on.

Windows users will also appreciate the Clear Desktop button, which doesn't appear on the standard Gnome panel.

Once again, there is a choice of four virtual workspaces. To the right of the running applications are further icons for logging off or locking the screen, a clipboard manager and a calendar.

HELP!
Despite the KDE and GNOME desktops' user friendliness, Linux can represent a daunting challenge for the newcomer, especially when you find that a peripheral device such as a printer or soundcard doesn't work properly.

The first port of call is the online documentation and both the GNOME and KDE desktops have 'getting started' documents that you will find in the main menu.

If you've bought Red Hat Linux, there's a whole CD-Rom full of documentation. Sooner or later, however, you may have to delve into the mysteries of the shell to access a network or configure new hardware.

This has its own built-in help system. If you open a console window (a window used for typing in text commands, just like the good old days) and type 'man mount', for example, you'll get the manual on the 'mount' command.

For an overview, you probably can't beat printed matter and we recommend getting hold of a general Linux textbook.

Of course the most important source of available help is from the Linux community itself.

As well as the sites mentioned in the resources section, practically all distributions contain links to FAQs and forums on their websites, such as mandrake expert.com, and you'll find that plenty of experienced users are more than happy to help out 'newbies'.