Platoon in the context of "LAPD Metropolitan Division"

A troop is a military sub-subunit, originally a small formation of cavalry, subordinate to a squadron. In many armies a troop is the equivalent element to the infantry section or platoon. Exceptions are the US Cavalry and the King's Troop Royal Horse Artillery where a troop is a subunit comparable to an infantry company or artillery battery. Historically the remainder of the Royal Horse Artillery used the term troop in the same manner but they eventually aligned with the rest of the Royal Regiment of Artillery in referring to troops as subordinate to artillery batteries.

Troops is often used to refer to the other members of one's company or cause, but because of its military connotations, it conveys a particularly altruistic type of dedicated worker. Traditionally, troops refers to the soldiers in a military.

Sergeant (Sgt) is a rank in use by the armed forces of many countries. It is also a police rank in some police services. The alternative spelling, serjeant, is used in The Rifles and in other units that draw their heritage from the British light infantry. The word "sergeant" derives from the Latin serviens, 'one who serves', through the Old French term serjant.

In modern hierarchies the term sergeant refers to a non-commissioned officer positioned above the rank of corporal, or to a police officer immediately below a lieutenant in the United States, or below an inspector in the United Kingdom. In most armies, a sergeant commands a squad or a section. In Commonwealth armies, it is a more senior rank, corresponding roughly to a platoon second-in-command. In the United States Army, sergeant is a more junior rank corresponding to a fireteam leader or assistant squad-leader; while in the United States Marine Corps the rank is typically held by squad leaders.

A company is a military unit, typically consisting of 100–250 soldiers and usually commanded by a major or a captain. Most companies are made up of three to seven platoons, although the exact number may vary by country, unit type, and structure.

Usually several companies are grouped as a battalion or regiment, the latter of which is sometimes formed by several battalions. Occasionally, independent or separate companies are organized for special purposes, such as the 1st Air Naval Gunfire Liaison Company or the 3rd Force Reconnaissance Company. These companies are not organic to a battalion or regiment, but rather report directly to a higher level organization such as a Marine Expeditionary Force headquarters (i.e., a corps-level command).

The Brazilian Expeditionary Force (Portuguese: Força Expedicionária Brasileira, FEB), nicknamed Cobras Fumantes (literally "the Smoking Snakes"), was a military division of the Brazilian Army and Air Force that fought as part of Allied forces in the Mediterranean Theatre of World War II. It numbered around 25,900 men, including a full infantry division, liaison flight, and fighter squadron.

Placed under United States command, Brazilian troops fought primarily in the Italian campaign from September 1944 to May 1945, while the Brazilian Navy and Air Force took part in the Battle of the Atlantic from mid-1942 until the end of the war. The FEB operated mostly at the platoon level, seeing heavy combat at the arduous Gothic Line and during the 1945 final offensive. By the end of the war, it took 20,573 Axis prisoners, including two generals and close to 900 officers. The division lost 948 men killed in action across all three services.

Tracer ammunition, or tracers, are bullets or cannon-caliber projectiles that are built with a small pyrotechnic charge in their base. When fired, the pyrotechnic composition is ignited by the burning powder and burns very brightly, making the projectile trajectory visible to the naked eye during daylight, and very bright during nighttime firing. This allows the shooter to visually trace the trajectory of the projectile and thus make necessary ballistic corrections, without having to confirm projectile impacts and without even using the sights of the weapon. Tracer fire can also be used as a marking tool to signal other shooters to concentrate their fire on a particular target during battle.

When used, tracers are usually loaded as every fifth round in machine gun belts, referred to as four-to-one tracer. Platoon and squad leaders will load some tracer rounds in their magazine or even use solely tracers to mark targets for their soldiers to fire on. Tracers are also sometimes placed two or three rounds from the bottom of magazines to alert shooters that their weapons are almost empty. During World War II, aircraft with fixed machine guns or cannons mounted would sometimes have a series of tracer rounds added near the end of the ammunition belts, to alert the pilot that he was almost out of ammunition. However, this practice similarly alerted astute enemies that their foes were nearly out of ammunition. More often, however, the entire magazine was loaded four-to-one, on both fixed offensive and flexible defensive guns, to help mitigate the difficulties of aerial gunnery. Tracers were very common on most WWII aircraft, except for night fighters, which needed to be able to attack and shoot down the enemy before they realized they were under attack, and without betraying their own location to the enemy defensive gunners. The United States relied heavily on tracer ammunition for the defensive Browning M2 .50 caliber machine guns on its heavy bombers such as the B-24 Liberator.

A platoon leader (NATO) or platoon commander (more common in Commonwealth militaries and the US Marine Corps) is the officer in charge of a platoon. This person is usually a junior officer – a second lieutenant or first lieutenant or an equivalent rank. The officer is usually assisted by a platoon sergeant. Some special units, such as specific aviation platoons and special forces, require a captain as platoon leader, due to the nature and increased responsibility of such assignments. Platoons normally consist of three or four sections (Commonwealth) or squads (US).