The Softlanding Linux System (SLS) distribution, which evolved into the Slackware distribution, is one of the oldest. Distributions in this branch generally made minimal or no changes to the original software packages before including them. Distributions using this format generally provided no native software management and depended on third-party utilities for package management and administration. These utilities were readily available and often included, so this was not necessarily a disadvantage.
These distributions are also known as Sorcerer/Lunar-Linux/Source Mage (SIS) distributions for the most common distributions using the format. These distributions are mostly obsolete and not often seen. However, the package format is still used by many software projects.
