Advanced Squad Leader (ASL) is a tactical-level board wargame, originally marketed by Avalon Hill Games, that simulates actions of squad sized units in World War II. It is a detailed game system for two or more players (with solitary play also possible). Components include the ASL Rulebook and various games called modules. ASL modules provide the standard equipment for playing ASL, including geomorphic mapboards and counters. The mapboards are divided into hexagons to regulate fire and movement, and depict generic terrain that can represent different historical locations. The counters are cardboard pieces that depict squads of soldiers, crews, individual leaders, support weapons, heavy weapons, and vehicles.