Arma (sometimes stylized as ArmA) is a series of first- and third-person military tactical shooters developed by Czech game developer Bohemia Interactive and originally released for Microsoft Windows. The series centers around realistic depictions of modern warfare (1980's cold-war era to speculative near-future settings) various perspectives. Combined arms warfare is depicted, and while the series primarily focuses on infantry, the games have a wide selection of usable vehicles, including combat vehicles, armored fighting vehicles, military helicopters, multirole combat aircraft, motorboats, and civilian passenger vehicles. Arma was originally conceived as a spiritual successor to Operation Flashpoint: Cold War Crisis after Bohemia Interactive lost the intellectual rights to the series. The first installment was released in 2006 and the most recent in 2022.

Arma: Armed Assault, known as Arma: Combat Operations in the United States, is the first Arma installment, released for Microsoft Windows in November 2006 (Czech Republic/Germany), February 2007 (Europe) and May 2007 (U.S.) using the Real Virtuality 2 game engine.

Queen's Gambit is downloadable content for Armed Assault; it was released in September 2007 (Europe) using the Real Virtuality game engine.

Arma 2 is the second full Arma installment, released for Microsoft Windows and released in June 2009 using the Real Virtuality game engine. The mod DayZ was released on this title, which requires the other standalone title Operation Arrowhead.

Reinforcements is a standalone expansion of the original Arma 2. It includes the downloadable content Arma 2: British Armed Forces and Arma 2: Private Military Company which can be purchased for any standalone Arma 2 title.

Arma 2: Operation Arrowhead is a standalone installment for Microsoft Windows, released in June 2010 with the Real Virtuality 3 game engine.

In June 2011, Bohemia Interactive re-released Operation Flashpoint as Arma: Cold War Assault, as Codemasters retain the rights to the Operation Flashpoint trademark. Owners of Operation Flashpoint: Cold War Crisis and the Game of the Year Edition may download and install the latest patch for free, and the game is available for purchase via a number of digital distribution channels. This release does not include the Red Hammer expansion, which was developed by Codemasters. The game uses the Real Virtuality game engine.

Arma 2: Firing Range is a standalone for Android and iOS and was released in July 2011.