Slackware - Linux for the Elite
Not many Linux distributions survive from the pioneer days of free and open source software. That was the brave frontier of the early 1990's, when software came on a stack of floppies, 16-bit color was a feast for the eyes, and configurations were done in text files in vi. We knew not of Google, we had gopher and archie and telnet. We dialed BBS boards and posted on Usenet and thought we had it all... because we did it on Slackware.
Slackware, as of this writing in 2006, has released version 11.0. It is the longest-lived of all Linux distributions, beating out the announcement of even the gray visage of Debian by a month, and Debian's first alpha release by a year. Slackware today comes with whistles and bells galore, the latest KDE and other desktops, the spiffiest graphic editors, compilers and interpreters for the hottest languages, and cutting-edge technology all around. It's only imposed limitation is that it's included software be rock-solid stable, yet it's "keep it simple" philosophy prevents undue complexity, so that stable does not mean "outdated by five years" like it does in Debian. It comes on three disks, yet seems to have more applications packed onto it than six disks-worth of other distros. Other distributions have spun off from it, but they are few. It is hard to improve upon perfection; SuSE and Wolvix are two notable derivatives, as is the Slax live CD project.
Patrick Volkerding in 1992 was looking for a free Lisp interpreter in order to complete a school project, and when he found one it would only run on a Unix-type system. So he grabbed a Linux kernel, some GNU utilities, and had just enough support to finish his project. He then started tinkering with it and adding to it, most notably writing simple text scripts to auto-configure everything. Slackware has since ever remained his personal vision of Linux - he has distributed his creation commercially through the Walnut Creek CDROM company, but has since built his own small company out of it. While Patrick never claims to have built Slackware to please anyone but himself, many others have taken to his unique vision. Slackware, the open source world's only one-man-show, has never been less than one-tenth of all installed Linux systems, and for a good many years was nine-tenths of it.
The benefit of having a one-person distro is that one other person can use it and wrap their heads around it easily. Slackware has never gone in for flashy GUI configuration tools, and yet it is simple to understand for those who care to dive in. Yet it has a quaint degree of under-the-hood tinkering. Package management, for instance, doesn't automatically download dependencies; the user must investigate what packages are needed by themselves. But tools are provided where frequently you'll never know the purpose of some arcane program until you need it, and then there it will be, the solution for the problem you have. Slackware takes much of it's flavor from BSD-style and Unix-style initialization scripts - everywhere you look, things are done sensibly and practically; not in the flashiest way, but the way that's guaranteed to work right the first time. The saying goes, when you learn another distribution of Linux you learn just that distribution, but when you learn Slackware you learn Linux!