Combat arm

Combat arms (or fighting arms in non-American parlance) is a collective name in a system of administrative military reference to those troops within national armed forces which participate in direct tactical ground combat. In general they include units that carry or employ a weapon system such as infantry, cavalry, and artillery units. The use of multiple combat arms in mutually supporting ways is known as combined arms.

In some countries, notably the British Army, the artillery units are categorised as combat support. Some armies such as the United States Army, classify combat engineers as a combat arm also, while armoured troops constitute a combat arm in name although many have histories derived from cavalry units. This is also true for the combat aviation units in many armed forces throughout the world.

Artillery is included as a combat arm primarily based on the history of employing cannons in close combat, and later in the anti-tank role until the advent of anti-tank guided missiles. The inclusion of special forces in some armed forces as a separate combat arm is often doctrinal because the troops of special forces units are essentially specialized infantry, often with historical links to ordinary light infantry units.

In Commonwealth Countries the combat arms in the Army are:

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