<operating system> /deb'ee`n/, *not* /deeb'ee`n/ The non-profit volunteer organisation responsible for Debian GNU/Linux and Debian GNU/Hurd. Debian's Linux distribution is dedicated to free and open source software; the main goal of the distribution is to ensure that one can download and install a fully-functional operating system that is completely adherent to the Debian Free Software Guidelines (DFSG).
Debian was begun in August 1993 by Ian Murdock, and was sponsored by the Free Software Foundation from November 1994 to November 1995. The name Debian is a contraction of DEB(ra) and IAN Murdock.
Debian's packaging system (dpkg) is similar to other popular packaging systems like RPM. There are over 2200 packages of precompiled software available in the main (free) section of the Debian 2.1 distribution alone -- this is what sets Debian apart from many other Linux distributions. The high quality and huge number of official packages (most Debian systems' /usr/local/ remains empty -- almost everything most Linux users want is officially packaged) are what draw many people to use Debian.
Another unique aspect to the Debian project is the open development; pre-releases are made available from Day 1 and if anyone wishes to become a Debian developer, all that is needed is proof of identification and a signed PGP or GPG key. There are over 400 Debian developers all around the world -- many developers have never met face-to-face, and most development talks take place on the many mailing lists and the IRC network.