Salvation and Steel is a set of free wargames rules for fantasy skirmishes. The author writes:
Salvation and Steel is a turn-based fantasy skirmish game designed to be played with 28mm miniatures on a 3' x 3' board with around 8 to 14 models per side. All materials needed to play Salvation and Steel, including the rules, are FREE or can easily be proxied.
The basic rules for Salvation and Steel aim to keep things relatively simple, and they've been written with a big focus on balancing the complexity of unit stats (attributes) and rules, in order to make things tactical and competitive without the players having to rules-check more than play during a game.
Simply put, the basic rules were not only written for new players, but also for younger players wanting to get into miniatures games and do something rather than read about it for longer than 5-10 minutes.
The advanced rules are, for the most part, an expansion rather than a replacement of the basic rules.