Mainly on the history of Systema.
Systema (Система, literally meaning The System) is a Russian martial art. Training includes, but is not limited to: hand to hand combat, grappling, knife fighting, and fire arms training. Training involves drills and sparring without set kata. It focuses mainly on controlling the six body levers (elbows, neck, knees, waist, ankles, and shoulders) through pressure point application, striking, and weapon applications.