Debian is a free and complete operating system. Debian GNU/Linux uses the Linux kernel (the core of an operating system), but most of the basic OS tools come from the GNU project; hence the name GNU/Linux.
Although it's a non-commercial project Debian is one of the most popular and well-respected Linux distributions. Advanced users are attracted to its stability, powerful package management and pure Open Source stance.
Debian systems currently use the Linux kernel, however, work is in progress to provide Debian for other kernels, primarily for the Hurd. The Hurd is a collection of servers that run on top of a microkernel (such as Mach) to implement different features. The Hurd is free software produced by the GNU project. Aside from Debian/Hurd, enterprising people can try out Debian/FreeBSD and Debian/NetBSD.
When you first install Debian, you get a "base system". The base system contains very little -- typically just enough to download the rest of whatever is needed for the system. Users may then use Apt to get most other packages, such as the X Window System. This format allows Debian to be installed on many older computers where space is scarce, and only the packages that will be used need be installed. While CD images for the Stable Debian 3.1 release (codenamed Sarge) exist, the preferred method for systems with an internet connection is to install at first just the base system (which can be downloaded in the form of a netinst CD for Sarge), and then install anything else you might need over the network using Apt. An even smaller image than the netinst image is the "businesscard iso".
For installing software after the base install, there are several front-ends to Apt to make the job easier (or at least to help you guess what packages are named). The most common of which is dselect since it is always on every Debian distribution (and even predates Apt). dselect is not recommended for beginners. Other Debian package management tools include aptitude and synaptic.
Debian was begun in August 1993 by Ian Murdock, as a new distribution which would be made openly, in the spirit of Linux and GNU.
"Debian" is pronounced "deb ee in" and rhymes with "simian". It comes from the names of the creator of Debian, Ian Murdock, and his wife, Debra.
Stable, Testing, Unstable, and Experimental
At any given time there are three Debian branches available: a Stable release, and the Testing and Unstable development branches -- currently codenamed "Lenny", "Squeeze", and "Sid", respectively. When the current testing cycle ends, Squeeze will become Stable, and a new codename will be given for Testing. Under current policy, Sid will remain "Sid" forever because someone noticed that not only is it named after the neighbor kid in "Toy Story" who breaks toys, but it also stands for Still In Development.
Experimental is a non-complete development branch used for testing highly experimental software. Debian follows very strict guidelines regarding which packages are allowed in each version, and this is what makes Stable stable. These guidelines are spelled out in the Debian Policy Manual, which includes the Debian Free Software Guidelines.
To upgrade from one of Debian's branches to another, see Upgrading to a different Debian branch
The current Stable Debian release 5.0 has been codenamed "Lenny". The Stable release is called stable because only bugfix (no features) are backported to it. This means that any programs or scripts in the Stable release are unlikely to break. But this comes at a price: Debian has a relatively slow release cycle and applications tend to become old by the time the next Stable release is about to come out. This misunderstanding over the purpose of the Stable release contributes to the perception of Debian being more primitive than other distributions.
The current Testing development branch is codenamed "Squeeze". The Testing branch starts as a copy of the new Stable release, and then has new features added to it from Sid. At any given time, the Testing branch is about as stable as an x.0 release of any other distribution. Because of this, the Testing branch, not the Stable release, is a better choice for most individual users. Since December 2004 the Testing branch has had its own security team that is separate from the security team for the Stable release.
Under current policy, the Unstable development branch will remain codenamed "Sid" forever because someone noticed that not only is it named after the neighbor kid in "Toy Story" who breaks toys, but it also stands for Still In Development. It is not recommended that you use Sid unless you enjoy filling out bug reports (and maybe fixing those bugs!).
The Experimental branch is not actually a full (self-contained) development branch -- it is meant to be a temporary staging area for highly experimental software. Dependencies missing are most likely found in Unstable (Sid). Debian warns that these packages are likely unstable or buggy and are to be used at your own risk. If you decide to use packages from Experimental, you are encouraged to contact the package maintainers directly in case of problems.
Debian-specific Installation, Configuration, Commands, and Files
- Package Management
- Obtaining security updates -- Security information is available in the Debian section
- Debian package management tricks
- The Unofficial Debian Forums (forums.debian.net)
- linuxquestions.org debian forum (www.linuxquestions.org)
- Debian mailing list archives at debian.org and the same at nabble.com
- www.debian.org -- Official website
- wiki.debian.org -- Debian wiki
- http://newbiedoc.berlios.de -- Debian NewbieDOC - Debian documentation FOR newbies BY newbies (and not-so-newbies).
- debianadmin.com -- Debian Step By Step Tutorials With screenshots
- www.debian-administration.org -- System Administration Tips and Resources
- debianhelp.co.uk -- Debian Articles,Howto's and really nice website for all debian admins
- planet.debian.net -- Planet Debian
- www.debiantutorials.org -- From Windows to a Debian GNU/Linux desktop, sans the geekness
- www.debuntu.org -- Debian/Ubuntu Tips & Tricks
- Search deb packages (www.debian.org)
- Standard bug tracking system (www.debian.org)
- HyperEstraier based search engine (merkel.debian.org)
- Official documentation (www.debian.org)
- Debian Reference Card (pdf) (people.debian.org)
- Installing Debian by Edd Dumbill for linuxdevcenter.com
- Debian GNU/Linux Desktop Survival Guide (www.togaware.com)
- Securing Debian Manual (www.nl.debian.org)
- Using a Sound Blaster Live Sound Card with Debian (uclinux.info)
- Install a Nice Bootsplash (www.formorer.de)
- Debian German Forum, very good (www.debianforum.de)