Specialist (abbreviated "SPC") is a military rank in some countries' armed forces. In the United States military, it is one of the four junior enlisted ranks in the U.S. Army, above private first class and equivalent in pay grade to corporal. Unlike corporals, specialists are not considered junior non-commissioned officers (NCOs). Specialist E-4 is the most common rank that is held by US Army soldiers.
the United States Navy maintained an enlisted rate of Specialist in the petty officer pay grade structure. This was to absorb directly appointed civilian experts needed in the rapidly expanding Navy. A seaman would typically be known as a specialist followed by a letter indicating what field the specialty was held. For instance, a Specialist (C) served as a "classification interviewer", while a Specialist (T) was a "navy teacher", among several other specialist designations.
The concept was first proposed in late 1941 and was approved by the Secretary of the Navy sometime in November or December of that year. The Navy started with four specialties in February 1942, expanding to twenty-two specialties and their associated sub-specialties by the war's end in 1945. The Coast Guard added an additional five exclusive specialties in 1943 (D, CW, PR, PS and TR); four were awarded double letters to avoid duplication. The WAVES added Specialist (U) for "Utility"—a general purpose title that was abolished in 1944 and merged with the similar Specialist (X), for "Specialist (Not Elsewhere Classified)".