Give a man Ubuntu, and he'll learn Ubuntu. Give a man SUSE, and he'll learn SUSE. But give a man Slackware, and he'll learn Linux. Well, so the old internet maxim goes, but while it's normally used with a touch of humour, there's a great deal of truth in it too.
Slackware is a curious animal, minding its own business while other distros roam the popularity plain and strive for dominance among their peers.
It's not trying to win enormous desktop market share, nor is it loaded with blinking lights, hold-your-hand graphical wizards and package managers that change with every release. Slackware is about as pure a GNU/Linux system as you can get – at least, without all the arduous leg work of Linux From Scratch.
There are many reasons why Slackware has a devoted base of hardcore fans, usually Linux old-timers but occasionally newcomers too. The top four:
It's almost entirely developed by one man.
The packages are not patched to the hilt.
It's comfortable in its own distrosphere.
It's very, very, very stable.