There are hundreds of GNU/Linux distributions around, each with its strengths and weaknesses. One that stands out from the masses is Debian. It is the only major distribution not developed (or even backed) by commercial vendors, but by a group of volunteers around the world. Its main features are robustness, great software package management, a huge software collection consisting of more than 15,000 pre-compiled packages ready to install and run, and a transparent and always helpful support system based on mailing lists and a bug tracking system.

But, there is something else that makes Debian special: No other distribution has seen as many offspring distributions as Debian has. Among them you’ll find customized Linux distributions for regional markets like LinEx (a government-driven project in Spain), or the shooting star Ubuntu (developed by a commercial vendor). The reason for this popularity is obvious: The Debian distro is not only free, but boosts flexibility and transparency.

If you use another Linux distribution and you are interested in changing, after you read this article you should install Debian for sure.

Introduction

Debian/GNU Linux is a universal operating system. You can install and run it not only on Intel- and AMD-based 32 and 64 bit PC systems, but also on different computer architectures like Compaq’s and Digital’s Alpha systems, ARM, Motorola 680x0 processors (m68k), SGI’s big-endian MIPS systems and Digital’s DECstations, Sun’s SPARC and UltraSPARC systems, the PowerPC (using IBM and Motorola processors), IBM S/390 mainframe systems and Hewlett Packard’s PA-RISC machines (hppa).

The Debian project doesn’t only produce a free (as in freedom, not only of charge) distribution, but is itself a strong supporter of free software. While many people spend hours discussing the differences between “free software” and “open source software”, Debian explicitely explains its position in two documents: “The Debian Free Software Guidelines” (DFSG), which defines what constitutes free software according to the Debian project; and the “Social Contract” with the free software community which positions the project itself and defines its links to the outside world:

• Debian will remain 100% free
• The project will give back to the free software community
• The project will not hide problems
• It prioritizes its users and free software
• It describes how to deal with work that does not meet its free software standards

You can read this document at Debian Social Contract.

The reason for this popularity is obvious: The Debian distro is not only free, but boosts flexibility and transparency

Differing from other Linux distributions, you’ll find not just one Debian version at a time, but three different releases: “stable”, “testing” and “unstable”. These are three different distributions. Each one ships with its own software packages which may or may not stem from the same original source-code version. For example: Debian “stable” at the time of writing shipped with a gimp package tagged 2.2.6, while “testing” at the same time included version 2.2.7. The “unstable” release uses the most recent software versions.

There is, however, only one official release: “stable”. Debian recommends it for production environments. The “testing” distribution contains packages that haven’t been accepted for the “stable” release yet, but after extensive testing will eventually move over. The “unstable” tree is the Debian developers’ working ground. At times this distribution can show problems like broken dependencies. Nevertheless, this distribution is usually completely functional since quality assurance (QA) is a task the Debian project takes serious. Packages in “unstable”, however, simply have not been tested in depth. If you wish to run a system equipped with the latest software versions “testing” is a good bet, but if you need a robust server you should choose “stable”.

Each of these distributions has a codename which (apart from “unstable”) changes with every release. The codename of the most recent “stable” distribution is “Sarge”, also known as Debian GNU/Linux 3.1. It was released June, 6th, 2005. The current “testing” distribution is nicknamed “Etch”, and “unstable” always remains “Sid”. All codenames are taken from Pixar’s movie “Toy Story” since a Debian project leader worked for this company. Obsolete releases are “Woody” (3.0), “Potato” (2.2), “Slink” (2.1) and “Hamm” (2.0).

Each distribution groups its packages by their software licenses:

• Main: includes all software compatible with the DFSG, for example the GNOME web browser “epiphany”
• Contrib: you’ll find free software that depends on non-free (according to Debian) software to run. “ant” (a Java development tool) is an example for this
• Non-Free: consists of software with a DFSG-incompatible license like “doom-wad-shareware”, a package that includes shareware game files for the 3D game DOOM

/etc/apt/sources.list configuration

The codename of the most recent “stable” distribution is “Sarge” also known as Debian GNU/Linux 3.1

Advantages and disadvantages on the technical level

Debian’s different approach becomes visible not only formally but also in technical details. It ships with a unique and robust package management system, centering around the APT tools and the “dpkg” utility, that Debian developers and users are especially proud of. It is the best way to install software quickly and easily on your machine—even as a newbie you’ll appreciate and love it. The package management system uses “dependencies” between packages to ensure correct software installation. Pre-compiled packages are distributed in a specific archive format with “.deb” file extension. While utilities like “dpkg” and “apt-get” are pure command-line tools, Debian also provides a set of package management front-ends to choose from like “dselect”, “aptitude” and “synaptic”. Most tools access software repositories via FTP or HTTP, provided the user wishes so. You type a single command, and Debian will download, install and configure the software for you. You don’t need to worry about where the software resides—as long as the configuration file /etc/apt/sources.list contains the repository’s proper URL. Each repository entry looks like the following line:

deb http://www.debian.org/debian sarge main contrib non-free

This means that the tools will download and install software belonging to the “Sarge” distribution from the main Debian web site. To install the GNU Image Manipulation Program (GIMP) the “root” user will now type e.g. the following command line:

#apt-get install gimp

The “apt-get” program will download the GIMP package and all packages it depends on (i.e. all software needed to run the GIMP).

Debian does not hide errors and bugs. Users can to send bugs using the bug tracking system _and the Debian developers can quickly access them by web or e-mail. Bugs are accessible to everybody because of the importance Debian places on _Quality Assurance. “The Debian Policy” is a specification for the standards of quality using by Debian.

On the other hand, Debian also has some disadvantages when compared with other distributions: its hardware auto detection is still way behind the appropriate functionality in SuSE or Mandriva, and the installation process doesn’t make it easy for beginners.