The major difference between the Debian distribution and other Linux distributions that are currently available is its open development model. This is not, however, the only difference between Debian and the other distributions.
The second, equally important difference, is Debian's strict adherence to the ``Free Software'' ideal. It is quite impressive, when you think about it, that this distribution is composed of freely redistributable software, complete with source code. Now, most other distributions also supply source code and these same programs, but they will also put packages into their distributions that can not be redistributed under certain conditions, without any concern for the legal problems that they deliver to their customer. Users of the Debian distribution can be assured that what they find in that distribution will have no constraints on the free distribution and modification of that software, leaving them free to build ``value added'' systems from this Distribution without fear that they will find themselves in court for misuse of someone else's intellectual property.
Debian provides areas within the archives for packages that do not meet these rigid standards, but are desired by the Debian community. Because of its free software status, the Debian packaging system can be used to package software that does not meet its own standards for free distribution.
Packages that are not freely distributable are found in the non-free section of the distribution. An additional category, called contrib is for those packages that would otherwise be free, except that they depend on some other package that is non-free. In this way, Debian provides a wide variety of software outside the distribution, in a way that protects its users from the legal ramifications of the non-free nature of that software.
There are substantial technical issues that separate Debian from the other distributions available today. Debian is dedicated to a strict interpretation of the Linux File System Standards, soon to be known as simply the File Hierarchy Standards. It is this strict adherence to these technical guidelines that helps make Debian such a dependably useful system. Foreign packages brought to a Debian system are typically easier to integrate into the system than with other Linux distributions.
As important as this standard is, the real technical superiority provided by Debian is its unique packaging system. This system allows for incremental upgrades of individual packages without the constant danger of ending up with a broken system. The modularity of the packaging system keeps each potential disaster localized within the narrow confines of the offending package. There are still plenty of ways to break the system, but the packaging system goes a long way toward protecting the system from such failures. Most of this protection comes from the dependency checking that is provided by this packaging system. Packages can declare their dependency on other packages and even declare that dependency to encompass a particular version of that other package. The installation software enforces these dependencies in a way that forces the dependencies to be satisfied before installation proceeds. This yields a functional package at the end of the installation, instead of one that will not operate for some strange reason.
Even with Debian's high quality, the complexity of Linux systems provides many ways to confuse the unwary user. Although Debian attempts to create an installation default that will fit the most general needs of the user, there are many areas where knowledge and skill are required to get the most value from this operating system. Debian provides for these needs with mailing lists. The debian-user mailing list is an open subscription list. To subscribe you simply send an e-mail message to:
debian-user-REQUEST@lists.debian.org
with the subject and message body containing the single word subscribe. This will bring you into contact with other users, potentially having had your problem in the past, who can help reduce your confusion. The strength of this list is that developers lurk on the list as well as users, so there is the possibility of getting expert advice from someone who understands your problem.
In addition, the debian-devel mailing list is also open to public subscription. Although its goals are far more technical in nature, much useful information can be gleaned from lurking on this list. As with the user list, a simple e-mail to:
debian-devel-REQUEST@lists.debian.org
with the subscribe statement in the subject line will result in mail from this list being sent to your e-mail address. The volume of these lists is quite high at times, which tends to scare folks away who are new to the Internet, but the quality of response is usually quite high. This is in stark contrast to other distributions, many of which don't even supply any e-mail address for questions. Those which do manage user mailing lists tend to be more closed and less helpful to the average user. Much of the difference comes from Debian's open development model, which welcomes the synergy created by multiple points of view. The helpful nature of these lists is way above average for this type of mechanism and most users find it a happy place to be while learning the ins and outs of the Debian system.
These differences have made Debian a competitive system with the other current leaders in the Linux community. The fact that Debian, without corporate sponsorship, has created a distribution that competes favorably against others with strong financial backing, is a surprising and remarkable achievement.