The rank of an officer in the United States Navy is indicated primarily by shoulder insignia, the number and width of the sleeve stripes and pin-on devices. Shoulder insignia are worn on white service coats, mess jackets, overcoats and khaki uniform coats. Sleeve stripes of gold braids encircle the lower part of blue coats of officers except those of overcoats, which carry stripes of black braid. A star is worn above the sleeve stripe of Line Officers. Miniature pin-on devices of the proper rank are worn on the collars of the working uniform.

During World War II, commissioned officers were appointed to the regular Navy (USN) and the Naval Reserve (USNR). Appointments in the Naval Reserve were for the duration of the war plus six months.

Appointments in the Naval Reserve were made from the following:

•  Graduates of aviation cadet schools (V-5)
•  Graduates of midshipmen's schools (V-7)
•  Graduates of women's reserve midshipmen's schools (V-9)
•  Graduates of Merchant Marine Cadet schools
•  Graduates of Naval Reserve Officer Training Corps (NROTC)
•  Qualified Warrant Officers and enlisted men

Appointments in the line of the Regular Navy were made from the following:

•  Graduates of the United States Naval Academy
•  Selected Naval Reserve Officers
•  Chief Boatswains, Chief Gunners, Chief Machinists, Chief Electricians,       Chief  Radio Electricians, together with respective Warrant grades, who were less than 35 years old and who had served for a period of at least 4 years.