Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
Slackware 1.0 was released by Patrick Volkerding exactly 18 years ago in 16 July 1993 in an official release when he was still a student. At that time, it was distributed under 24 disks (yes, floppy disks) and it only has two series, A and X. No one will ever thought that it's now being the oldest maintained Linux distribution up to now.
In 1993, there wasn't much Linux distribution. Slackware is one of the first batch of Linux Distribution at that time along with SLS, Debian Linux, YggDrasil, and MCC Interim. It turned out good so that many Linux distributions are now based on Slackware, such as SuSE (turned OpenSUSE), VectorLinux, Slax, ZenWalk, Salix, and many more.
Today, it's released using a DVD (and an option of using 6 CDs) and it has so many directories inside. It supports so many hardwares thanks to the Linux 2.6.x (soon to be replaced by 3.0 series) series being developed by great developers around the world under the command of Linus Torvalds and also utilizes the best open source applications available provided by upstreams.