|Platoon or Troop
A Platoon is an Infantry Unit, usually commanded by a Lieutenant. It's generally made up of about 25 to 30 soldiers.
A Troop is a Tank Unit with a similar structure. It consists of four tanks, each with a crew of four.
Company or Squadron
A Company is made up of three Platoons and an HQ. It's normally commanded by a Major and contains about 150 officers and soldiers.
A Squadron is made up of three Troops and an HQ, and has a similar structure.
Battalion or Regiment
A Regiment is arguably the key unit in the British Army. It's made up of three Squadrons, a Support Squadron and an HQ Squadron and usually contains between 450 and 650 soldiers. Commanded by a Lieutenant Colonel, it has both administrative and tactical capabilities. Each Regiment has its own number and title, with distinctive designations that reflect its historical traditions. These distinctions include the regimental Battle Honours, Colours or Guidon, cap badge, crossbelt plate, collar badge and buttons. Over time, these traditions help to build each Regiment's unique 'family' and 'spirit'.
A Battalion is made up of three Rifle Companies, a Support Company and an HQ Company and has a similar structure.
A Brigade is usually made up of a group of three Regiments or Battalions that have joined together for a specific purpose. Its structure depends on its aims and goals - but a Brigade can often contain 5,000 soldiers or more.
A Division is similar to a Brigade, but on a much larger scale. It's usually made up of at least three or four Brigades.
Units drawn from these Corps are often used to support Regiments, Battalions, Divisions and Brigades where necessary (depending on the requirements of a specific situation).