Rear Admiral (Upper Half) is a senior commissioned officer rank of the UNSC Navy. It is equal with the rank of Major General in the UNSC Marine Corps, UNSC Air Force, and UNSC Army. In informal settings, Rear Admirals (Upper Half) are typically referred to simply as "Admiral." A Rear Admiral (Upper Half) may be also referred to as a "two-star Admiral" to distinguish it from the other ranks of Admiral, so named for the two star rank insignia worn on the uniform.