ArmA is a military simulation video game series developed by Bohemia Interactive Studio, an independent Czech computer and console game developer based in Prague, Czech Republic, and published by various publishers since 1999. The goal of the series is to simulate real life military experience.
After the first installment Operation Flashpoint, Bohemia Interactive Studio parted ways with their publisher Codemasters. BIS retained the engine, while Codemasters retained the name. BIS rebranded their series as ArmA, while Codemasters developed their own mil-sim sequels to Operation Flashpoint. For the ease of categorizing, Operation Flashpoint games will be grouped alongside ArmA games on this site.
BIS's sister company, the Bohemia Interactive Simulations (BISim), also develops the VBS (Virtual Battlefield Systems, later Virtual Battlespace) military simulator, built on the same foundations as the ArmA series but offering far more advanced features. VBS has three iterations, VBS1 through 3. They are in use by multiple armed forces around the world for educational purposes, and are the dominant military simulator software with few competitors. The ArmA series is in essence the streamlined consumer version of the VBS military simulator (though BISim and BIS have been separate for a while).