Drill master

A drill instructor is a non-commissioned officer in the armed forces or police forces with specific duties that vary by country. For example, in the United States armed forces, they are assigned the duty of training new recruits entering the military.

Drill instructors within the U.S. armed forces have different titles in each branch of service. In the United States Air Force, they are known as "Military Training Instructors", or MTIs. The United States Navy uses Marine Corps drill instructors at their Officer Candidate School, but only Chief Petty Officers called "Recruit Division Commanders", or RDCs at their recruit training. Within the United States Army, drill instructors are given the title of "Drill Sergeant". The United States Coast Guard gives the title of "Company Commander" to their drill instructors. The United States Marine Corps is the only branch of the U.S. armed forces where drill instructors are titled as "drill instructors". Drill instructors are referred to as "sir" or "ma'am" by recruits within the USAF, USMC, and USCG (for the first few weeks of basic training, until recruits are instructed to refer to their company commanders by their proper rank). Within the USN, recruits must refer to their RDCs by their proper ranks. Recruits in the United States Army must refer to their drill sergeants as such: "drill sergeant".

The instruction and indoctrination given by the drill instructors of the various U.S. military branches includes instruction in customs and practices of military life, instruction in the proper execution of military drill, instilling discipline and willingness to immediately obey all lawful orders given by superiors, and oftentimes, basic armed and unarmed combat training.

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