A captain is a rank of commissioned officer in the military. This rank is used by different militaries around the world and by the major branches of the United States Armed Forces. A U.S. Army captain is usually in charge of a company, which may consist of 100 to 200 soldiers, depending on the type of unit. He is typically responsible for training, organizing and supplying the men under his command. An army captain — whether in the U.S. Army or elsewhere — also may serve as a staff member for a higher-ranking officer or serve a specialist role within an army.
Candidates hoping to become an army captain need to complete several stages of preparation, including basic military training and various leadership courses related to the officer's command. In the U.S. military, a future captain must complete Officer's Candidate School, attend the U.S. Military Academy, complete a Reserve Officer's Training Corp (R.O.T.C.) program or receive a direct commission. Most U.S. Army captains in combat-related areas will begin their careers at lower ranks to develop the skills and leadership qualities necessary for commanding a larger contingent of soldiers.
The role of an army captain is heavily reliant on the types of units under his command. An infantry captain is usually responsible for a company of soldiers, which includes four platoons of men and additional support personnel to assist the commander in his duties. An infantry captain must coordinate with other company commanders within a battalion or regiment and usually takes orders from a lieutenant colonel or colonel. He must determine the best ways to execute the orders and missions assigned to his company and give assignments to lieutenants in charge of each platoon.
A company of armor, such as tanks and other fighting vehicles, is known as a troop and also will be led by a captain. In the U.S. Army, armor captains will typically be in charge of 12 tanks spread among three platoons, along with a two-tank command element. As with the infantry commander, the tank captain will be responsible for coordinating with other elements of the U.S. Army and completing the missions assigned to him by his superiors.
The designation of army captain also can be given for certain non-combat officers within a military. Army doctors, chaplains and lawyers usually receive the rank of captain by direct commission upon their entry into the U.S. Armed Forces. These officers typically possess civilian degrees in certain fields and provide valuable support services for the military.