Slackware was the first Linux distribution to achieve widespread use. It was started by Patrick Volkerding in late 1992. He had gotten introduced to Linux when he needed an inexpensive LISP interpreter for a project. At that time, there were very few distributions, so Patrick went with the distribution from Soft Landing Systems (SLS Linux).
However, SLS had some problems, so Patrick started to fix little bugs as he found them. Eventually, he decided to merge all of those fixes into his own distribution for himself and friends. This private distribution quickly gained popularity, and Patrick made it available to the public under the name of Slackware.
Along the way, Patrick added new things to the distribution like a user-friendly installation program based on a menuing system and the concept of package management. This allows users to easily add, remove, or upgrade software packages from their system.