Age of Empires II is a real-time strategy game released in 1999, developed by Ensemble Studios. Players control a civilization, gathering resources, building structures, and training armies to conquer opponents. The game features various historical civilizations, each with unique units and technologies. The gameplay includes single-player campaigns, skirmishes against AI, and multiplayer modes. Players advance through different ages, unlocking new technologies and units. Age of Empires II has received several expansions and remastered versions, maintaining its popularity in the gaming community for over two decades.