Ask four militaries what a squadron is and you will hear four answers
Military vocabulary sounds precise, but a single word can mean wildly different things. To most admirals a squadron means a cluster of warships. To most air commanders it means a unit of aircraft. In the United States Army it is a battalion-sized cavalry outfit, and in Commonwealth armies merely a company-sized piece of a regiment.
The confusion runs deeper. A British or Canadian armoured regiment is really battalion-sized and splits into squadrons, which split into troops. An American cavalry squadron, also battalion-sized, instead divides into troops and then platoons. In the French model, used by many African armies, a company breaks into sections built from three combat groups of seven soldiers each, plus vehicle crews and a headquarters with two snipers.
Formal ranks within a hierarchy go back to Rome. Each legion held around 5,000 soldiers under a commander called a legate, and was divided into centuries led by centurions. Much later, about 1805, Napoleon introduced the corps, a flexible grouping of two or more divisions that gave commanders more room to manoeuvre, and most modern armies kept it.
Labels can mislead even when they match. Early in the Second World War, a Red Army division was often only as big as another country's regiment or brigade, one step down the usual ladder. What most nations called an army group, the Soviets called a front. Meanwhile German army groups on the Eastern Front, such as Army Group Centre, far exceeded typical sizes.
Navies organise differently from armies. An army unit can keep the same people and equipment for years, but naval groupings form and dissolve as missions demand, so formal naval hierarchy above the flotilla is loosely followed. At the top, the five-star titles of fleet admiral and admiral of the fleet have been largely honorary since the 1990s. Major navies are now led by three- or four-star admirals, while small forces such as New Zealand's may answer to a rear admiral, a commodore or even a captain.
Source: Military organization
