Rank in its military sense is the character or quality bestowed upon the men of the military and naval services which carries with it the eligibility to exercise command or authority over other members of the services within the limits prescribed by law and regulation. Rank is divided into many different grades to mark the relative positions of the persons upon whom it is conferred and to limit the extent of the authority carried with it. In all of the services of the United States, “Commissioned Officers” are those who have received a commission from the President “by and with the advice and consent of the Senate of the United States”; and “Appointed Officers” are those who are appointed by the President or by his order but who are not “commissioned” and confirmed by the Senate. In the Army the “Appointed Officers” are Aviators, Army Field Clerks, Field Clerks Quartermaster Corps, and Cadets at the Military Academy. In the Navy the “Appointed Officers” are Warrant Officers and Midshipmen. In the Marine Corps the “Appointed Officers” are Warrant Officers. In the Army and Marine Corps “Noncommissioned Officers” are selected enlisted men who are appointed to the various ranks of enlisted authority by orders from their proper military commanders. “Petty Officers” in the Navy are appointed enlisted men corresponding to noncommissioned officers in the Army and Marine Corps. The “Title” of an officer is the name of the rank or grade in which he holds a commission, the formal term by which he is officially addressed in communicating with him, although custom sanctions some variations from this general rule. In the Army and the Marine Corps all commissioned officers, line and staff, have positive rank in the several grades, and it is customary to address them when communicating orally with them by the name of the rank they hold, the variations being that all General Officers (Generals, Lieutenant Generals, Major Generals and Brigadier Generals) are commonly addressed as “General,” that Lieutenant Colonels are addressed as “Colonel,” and that all subalterns (First Lieutenants and Second Lieutenants) are addressed as either “Lieutenant” or as “Mister.” In the Navy it is customary to address officers of the Line (the command branch of the service) by the name of their rank, and to address officers of the Staff Corps either by the name of their rank or as “Mister,” for all except officers of the Medical Corps, who are usually addressed as “Doctor.” The exceptions to this rule are that all Flag Officers (Admirals, Vice Admirals and Rear Admirals) are usually addressed orally as “Admiral,” and that Lieutenant Commanders, Lieutenants and Ensigns are often addressed as “Mister.” It is customary to address the Warrant Officers of the Navy and Marine Corps as “Mister.”