While "Command HQ" was recognized as one of the earliest real-time strategy games for the PC, it was preceded by the "Ancient Art of War" and other trailblazers. Unlike these games it has elements of unit production and resource use that would later be expanded in games like "Dune II" and "Command and Conquer". Its user interface was also ahead of its time in its use of the mouse to plot movement and the clear presentation of game data. Another innovation was for two players to play against each other with their computers connected over a modem. Players simulate a variety of global wars through time - 1918 (World War I), 1942 (World War II), 1986 (World War III), 2023 (alternative history) and a post-apocalyptic future in which each player starts from a random position with no knowledge of their opponent's starting position and must explore and expand to confront them.