Military organization

The armed forces of a state are its government-sponsored defense and fighting forces and organizations used to further the objectives of the state. They exist to further the foreign and domestic policies of their governing body. In some countries paramilitary forces are included in a nation's armed forces.

In democracies and most other government types, the armed forces are typically linked to the government through a civilian government department. These may be known as a Department of Defense, Department of War, or Ministry of Defence.

Services

The military is divided into several services (also called branches). The three most common are armies, navies, and air forces. Some nations also organize their marines and their special forces as independent services. A nation's coast guard may also be an independent branch of its military (though in many nations the coast guard is actually a law enforcement or civil agency). The French military structure, which is copied in other nations, includes the three traditional services and a fourth service which is the Gendarmerie. The former Soviet Union organized the Strategic Rocket Forces as a separate branch (Raketnye Vojska Strategicheskogo Naznachneiya) and the Russian government has continued that organization.

It is worthwhile to make mention of the term joint. In western militaries, a joint force is defined as a unit or formation comprising representation of combat power from two or more branches of the military.

Units, formations, and commands

It is common, at least in US and Commonwealth militaries, to refer to the building blocks of a military as units and formations.

A typical unit is a homogeneous military organization, either combat, combat support or non-combat in capability, that includes service personnel predominantly from a single Arm of Service, or a Branch of Service, and its administrative and command functions are integrated (self-contained). Anything smaller than a unit is considered a "sub-unit" or "minor unit".

A formation is a composite military organisation that includes a mixture of integrated and operationally attached sub-units, and is usually combat-capable. Formations include brigades, divisions, wings, etc.

Different armed forces, and even different branches of service of the armed forces may use the same name to denote different types of organizations. An example is the "squadron". In most navies a squadron is a formation of several ships; in most air forces it is a unit; in the U.S. Army it is a battalion-sized cavalry unit; and in Commonwealth armies a squadron is a company-sized sub-unit.

In a military context, a command is a collection of units and formations under the control of a single officer. Although during the Second World War a Command was also a name given to a battle group in the US Army, in general it is an administrative and executive strategic headquarters which is responsible to the national government or the national military headquarters. It is not uncommon for a nation's services to each consist of their own command (such as Land Force Command, Air Command, and Maritime Command in the Canadian Forces), but this does not preclude the existence of commands which are not service-based

Hierarchy of modern armies

This gives an overview of some of the terms used to describe army hierarchy in armed forces across the world. Whilst it is recognized that there are differences between armies of different nations, many are modeled on the British or American models, or both. However, many military units and formations go back in history for a long time, and were devised by various military thinkers throughout European history. For example, Corps were first introduced in France in the 18th Century, but have become integrated into the organization of most armies around the world. Readers interested in the detailed specifics of a national army (including the British and American) should consult the relevant entry for that country.

APP-6A Symbol	Name	No. of personnel	No. of subordinate units	Unit leader
XXXXXX	region or theater or front	1,000,000 +	10+ army groups	general or army general or field marshal
XXXXX	army group	100,000 +	2+ armies	general or army general or field marshal
XXXX	army	50,000-80,000	2-4 corps	colonel general or general or army general
XXX	corps	30,000-50,000+	2+ divisions	lieutenant general
XX	division	10,000–20,000	2-4 brigades or regiments	major general
X	brigade	3000–5000	2+ regiments or 3–6 battalions or Commonwealth regiments	brigadier general, brigadier or colonel
III	regiment or group	2000–3000	2+ battalions or U.S. Cavalry squadrons	colonel
II	battalion (of infantry), (U.S. Cavalry squadron or Commonwealth armoured regiment)	300–1000	2–6 companies, batteries, U.S. Cavalry troops, or Commonwealth squadrons	lieutenant colonel
I	company (of infantry), artillery battery, U.S. Cavalry troop or Commonwealth armoured squadron	70–250	2–8 platoons or Commonwealth troops	chief warrant officer and captain or major
•••	platoon or Commonwealth troop	25–60	2+ squads, sections, or vehicles	warrant officer and first or second lieutenant
••	section or patrol	8–12	2+ fireteams	corporal to staff sergeant
•	squad or crew	8–16	2+ fireteams or 1+ cell	corporal to staff sergeant
Ø	fireteam	4–5	n/a	lance corporal to sergeant
Ø	fire and manoeuvre team	2	n/a	any/Private First Class

Rungs may be skipped in this ladder: for example, typically NATO forces skip from battalion to brigade. Likewise, only large military powers may have organizations at the top levels.

Army, army group, region, and theatre are all large formations that vary significantly between armed forces in size and hierarchy position. Divisions were the traditional level at which support elements (field artillery, hospital, logistics and maintenance, etc.) were added to the unit structure. For example, regiments and battalions did not have such support assets. Since World War II, brigades are having such support units added, and since the 1980s, regiments have been receiving support elements. A regiment with such support elements is called a regimental combat team in US military parlance, or a battle group in the UK and other forces.

Different armies and countries may also use traditional names, creating considerable confusion: for example, a British or Canadian armored regiment (battalion) is divided into squadrons (companies) and troops (platoons), whereas an American cavalry squadron (battalion) is divided into troops (companies) and platoons.

The Red Army used the same basic organizational structure. However, in the beginning of World War II many units were greatly underpowered and their size was actually one level below on the ladder than usually used elsewhere, for example, a division in the early-WWII Red Army would have been about the size of most nations' regiments or brigades. At the top of the ladder, what other nations would call an army group, the Red Army called a front.

The Wehrmacht Army Group during the Second World War, particularly on the Eastern Front, such as Army Group Centre significantly exceeded the above numbers, and were more cognate with the Soviet Strategic Directions.