Different styles of rank insignia are worn on different uniforms of the United States Marine Corps.Commissioned officers carry the "special trust and confidence" of the President of the United States.Because warrant officers are officer-level technical specialists, they generally do not exercise command outside of their specialty.The first sergeant and sergeant major ranks are command-oriented senior enlisted advisors, with Marines of these ranks serving as the senior enlisted Marines in a unit, charged to assist the commanding officer in matters of discipline, administration, and the morale and welfare of the unit.Musicians in the United States Marine Band wear insignia with lyre in the center as opposed to the crossed rifles, to denote their lack of a combat mission; full-service Marines who are attached to the 10 field bands of the Operating Forces and Supporting Establishment continue to wear their normal rank insignia.
L to R: Evening Dress coat, Dress Blue coat, Service Dress coat, Service Dress "B" and "C" shirt, and combat utility pin-on insignia for a Staff Sergeant