1.5. Distributions

At present, there are dozens of versions of Linux, called distributions. Despite this embarrassment of riches, you can easily see that they are similar to one extent or another, because most of them have the same roots. Many distributions, for example, are built on the base of the Red Hat Linux brand. Although Linux is free, its distributions are not quite so. Just like Windows or other commercial software, you have to buy Linux from software vendors. Their license agreements, however, are much more generous than those for commercial operating systems. For example, after buying one copy of Linux, you can install it on as many computers as you want to. Usually, vendors modify the installer slightly (this mostly consists of "dabbing some make-up" to the graphical interface), change the list of application software, and then sell it under their brand name . In most cases, however, the system's kernel and the application software are not changed.

But even distributions of different origins almost always use the K Desktop Environment (KDE) or/and GNU Network Object Model Environment (GNOME) graphical shells. If, in an unlikely case, the distribution does not supply these shells , you can easily obtain them from third-party sources and install them yourself. Consequently, all distributions use the same graphical interface, regardless of their origins.

In this book, I will consider the Red Hat distribution of Linux because it is the most widely used (by some accounts, it holds about a 50% share of the Linux market). Don't worry if you are using another distribution: You will not notice any significant differences. The biggest differences among distributions show up mostly during the installation process, but even then only in the way the graphical interface is implemented.

The abundance of distributions is the weakest spot of the Linux operating system. This problem stems from the open -source nature of the software. When you start working with the operating system or, more exactly, with its application software you will see that numerous operations are not standardized. For example, you have to press the <Ctrl>+<C> key combination to exit one program, <Ctrl>+<X> to exit another, and <Ctrl>+<Q> to exit yet another one. This is a serious problem that complicates handling the system.

In this respect, Windows is more standardized and is easy to become used to although in Windows there has been a tendency to march to the beats of different drummers of late. For example, the appearance of programs has become unpredictable. In Windows XP, some programs have kept up with the times and have the XP look, but some have not and have the pre-XP look. Menus and toolbars change from Office 2000 to Office XP to Office 2003. In Linux, despite no standards, all menus and toolbars are the same, and you don't have to become used to new ones from one program to another.

The price for one copy of Linux is much lower than that for Windows. Moreover, the distribution package includes a huge number of application software, such as office applications, Internet utilities, and graphics editors. Consequently, having installed a Linux distribution you can immediately use the system to solve most office and home tasks (not the laundry, though).

Microsoft's Paint, WordPad, and other application programs supplied with the operating system are too unsophisticated for anything but the most basic tasks. To obtain corresponding application software of acceptable performance, you will have to spend thousands of extra dollars. Therefore, the actual price of a ready-to-work Windows-based workstation is much higher than the price of the operating system, because application software is to be purchased in addition to the operating system.

Comparing the combined cost of the operating system and the application software, Linux is significantly less expensive than Windows. Microsoft, however, provides free support for its product; whereas to obtain any decent support for Linux, you must have access to the Red Hat network, which is rather expensive. Thus, support expenses can make the ownership costs of the two operating systems equal. This is why I am not saying that Linux is better than Windows because it is free; that is not quite right. But you will see that Linux is better because it is more flexible, more reliable, and, if it is configured properly, more efficient. These properties are more important than the price, and you will see that all of them are inherent to Linux.

Consider the main Linux distributions available on the market. Remember that Linux is just the kernel, and most of the application software, services, and graphical shells are provided by third-party developers. Exactly which application software is supplied with the operating system depends on the distribution's developer.

In your choice of distribution, you should be guided by what you want the system to do. This is not, however, a mandatory requirement, because any distribution can provide the necessary power and security if you supplement it with third-party software packages.

1.5.1. Red Hat Linux

This distribution is considered the classic and the trendsetter of this operating system, because the creator of Linux, Linus Torvalds, works for Red Hat. You can either purchase this distribution or download it for free from the company's site at www.redhat.com . Red Hat produces two versions of its Linux distribution: one for server solutions and one for client computers. The interface of the latter version is becoming increasingly user -friendly and is suitable for any home task.

Installing this distribution has been easy and convenient for a long time. I will consider installing Red Hat in Chapter 2 , and you will see that there is nothing difficult about it.

All Linux distributions have a bad reputation for not being user-friendly where application software installation is concerned . The latter is usually supplied as the source code that has to be compiled. Red Hat made installing programs, including the Linux kernel, easy with the help of the Red Hat Package Manager (RPM), which may be viewed as a counterpart of the Windows installer.

Many Linux enthusiasts hope that the Red Hat initiatives will make their favorite operating system easy for everyone to use and enable it to move ahead of the competition.

If you are looking for a distribution for a server, I urge you to take a serious look at the Red Hat distribution or one of its clones . Red Hat takes good care of the security of its product and tries to correct any errors in it as soon as possible.

1.5.2. Slackware

It is this distribution that introduced me to Linux. You can download it from www.slackware.com . This is one of the oldest and most difficult distributions for home users. There is still no easy and convenient installation utility for it, and most operations have to be carried out in the text mode. You can install the KDE or GNOME graphical interfaces and other utilities that make life easier when using this distribution, but this will not make the installation itself easier.

If you have never worked with Linux, I would recommend that you do not start your acquaintance with this distribution and select a distribution that is easier to work with.

1.5.3. SUSE Linux

I have worked with various software packages produced by German developers and can say that describing their usability as "leaving a lot to be desired" would be a gross understatement. Their programs, at least those that I had the misfortune of working with, are cripples from birth. But the Linux kernel from SUSE ( www.novell.com/Unux/suse/ ) is a pleasant exception. This distribution has a nice interface, and its huge database of drivers provides excellent hardware support. SUSE programmers have also added a utility collection named YaST to the distribution, which makes administering it much easier. But as you will see, although the ease of use is a desirable quality, maximum efficiency can be achieved only by directly editing configuration files.

I would only recommend SUSE for amateurs or for use on client computers.

1.5.4. Debian

Although many developers of distributions seek commercial gain, many distributions are available for free. The main and largest of such distributions is Debian ( www.debian.org ). This product is created by professionals around the world for their own use, but anyone can use their distribution.

Debian differs from the classical Red Hat, and you may run into problems because some of its configuration files are located in different places than in other distributions. The problems do not end here. Like all noncommercial products, this distribution is more difficult to use than commercial software. Its developers position Debian as a dependable operating system, and they do a good job of it. But they do not care much for regular users, so conquest of the home computer market by this distribution in the foreseeable future is unlikely.

There are many other distributions, spanning the range from large and powerful systems including all necessary software to small distributions fitting on a diskette and running on old computers.

It would be difficult to describe all of them in one book, and there is no need to do so. The main intention of this book is to teach you how to create a secure and efficient system. This is difficult to accomplish because of the large number of distributions; security specifics can differ among distributions and even among kernel versions.

This concludes the introduction to Linux. I will move on to installing this operating system, allowing you to acquire knowledge of it firsthand.