There are several paths to becoming a commissioned officer including Army ROTC, the United States Military Academy at West Point or the United States Merchant Marine Academy at Kings Point, and Officer Candidate School. Certain professionals, physicians, nurses, lawyers, and chaplains are commissioned directly into the Army. But no matter what road an officer takes, the insignia are the same.
The highest officer rank is the five-star general (General of the Army) and the lowest is the second lieutenant.
Address all personnel with the rank of general as "General (last name)" regardless of the number of stars. Likewise, address both colonels and lieutenant colonels as "Colonel (last name)" and first and second lieutenants as "Lieutenant (last name)."
Warrant Officers are single track, specialty officers with subject matter expertise in a particular area. They are initially appointed as warrant officers (in the rank of WO1) by the Secretary of the Army, but receive their commission upon promotion to Chief Warrant Officer Two (CW2).
Technically, warrant officers are to be addressed as "Mr. (last name)" or "Ms. (last name)"; however, many personnel do not use those terms, but instead say "Sir", "Ma'am", or most commonly, "Chief."
Sergeants are referred to as NCOs, short for non-commissioned officers. Corporals are also called "hard stripes", in recognition of their leadership position. This distinguishes them from specialists who might have the same pay grade, but not the leadership responsibilities.
Address privates (E1 and E2) and privates first class (E3) as "Private (last name)." Address specialists as "Specialist (last name)." Address sergeants, staff sergeants, and sergeants first class as "Sergeant (last name)." Address higher ranking sergeants by their full ranks in conjunction with their names.
All Sergeant ranks from E-5 SGT to E-8 MSG are simply referred to as "Sergeant (last name)". First Sergeant as "First Sergeant (last name)", Sergeant Major, Command Sergeant Major, and Sergeant Major of the Army as "Sergeant Major (last name)". Privates are usually referred to simply by their last names.
