About the Linux™ kernel, GNU/Linux, and Distributions

The term "Linux" is a trademark by its creator, Linus Torvalds. Specifically, it refers to the kernel that Linus wrote, which adapted some concepts from the AT&T Unix industrial operating system, bringing a similar system to personal computers. Many other developers have joined in the effort to build this alternative kernel.

A kernel is a small but critical part of a computer's operating system. It manages and standardizes the ways that programs can communicate with the devices installed on the computer. Since a kernel has no user interface, it is by itself incomplete. It requires programs that can bridge the gap between man and machine.

Linus and other developers used some commonly available tools offered by the Free Software Foundation to build the kernel, and also to build a small library of useful Unix-like tools to accompany it. The FSF's own Unix alternative is called GNU. GNU is pronounced as guh noo and stands for "GNU's Not Unix". Since the kernel is only useful in conjunction with such a library of tools, and the tools chosen come from the GNU project's work, some people led by GNU's Richard Stallman feel that Linus' new operating system should be called "GNU/Linux," though that is somewhat of a political stance and not a widely developed trademark.

Even with the GNU tools and Linux kernel combined, the system is still not be able to do much useful work for anyone except cover its own system maintenance needs. The basic tool set allows someone to edit a few scripts, manage user accounts, monitor some hardware devices, and do some perfunctory software development, but still does not offer any real applications for end-users themselves.

A very large and growing number of software packages are designed to run on the Linux (or GNU/Linux) operating system. These packages are from many different software developers, for a wide range of end-user tasks, user interfaces, and more complex system-maintenance methodologies. From network services to office applications to games to artwork tools, there are thousands of end-user packages now available for Linux.

As the number of available packages grew, the concept of "distributions" or "distros" took off. Some organization of people, be they experts, fans, zealots or even whole companies, will choose which software packages are useful together, customize a few of them to meet their own needs, and create a larger distro package containing them all. The group then maintains and updates the included packages as new software or bug fixes become available. There are many well-established distributions, but some well known names are Red Hat Linux, Debian GNU/Linux, Mandrake Linux, and SuSE Linux.

Each distribution may include roughly the same scope of software and often even the exact same packages. The differences between distros usually comes down to the three S's: security, stability, style. Since each software package is maintained and developed by different people, these distribution groups tend to have unique priorities on these traits. Some focus on the latest new features, others on keeping only the battle-proven elements. Some focus on ease of use or on eyecatching interfaces, others on powerful system maintenance features. Some focus on corporate needs and industrial challenges, and others focus on the desktop and a wide spectrum of end users' requirements.

Finding the distribution that is right for your purposes will come from some experimentation and weeding through the understandably biased advice from the fans of each distro.

For more information on popular distributions, see http://www.distrowatch.com/ for the Top 10 Linux Distributions, updated regularly. This page also links to the homes of each distribution.

Some helpful google searches may be linux linus torvalds, gnu project free software, gnu richard stallman, and linux kernel trademark.

Contact Ed Halley by email at ed@halley.cc. Text, code, layout and artwork are Copyright © 1996-2005 Ed Halley. Copying in whole or in part, with author attribution, is expressly allowed. Any references to trademarks are illustrative and are controlled by their respective owners.