To begin, there are nine levels of enlisted rank in the United States Army. Rank begins with the Private, and ends with the Sergeant Major of the Army. Along with each proper rank name, is an abbreviated rank identifier and an enlisted grade, or pay grade. The enlisted grades also start at E1 and end at E9. Four grades, E4, E7, E8 and E9, are distinguished because they each have multiple ranks associated with them.
People usually recognize that soldiers wear 'stripes' on their sleeves and collars. There are two types of stripes that are used with one another. The stripes that point up are called chevrons. The lower stripes that attach to the chevrons are called arcs or rockers.
Private, PV1, E1 – This is a basic recruit rank and grade. The private wears no insignia. His sleeve and collar are bare.
Private, PV2, E2 – The Private wears the insignia of one chevron on his sleeves and collar. Advance to the rank of E2 is usually automatic upon completion of six months service.
Private First Class, PFC, E3 – The Private First Class wears insignia of one chevron and one rocker. Advance to the rank of E3 is usually automatic upon completion of 12 months service. The E1, E2 and E3 are all addressed as 'Private'.
Specialist 4, SP4, E4 – The Specialist is a somewhat unique rank. This is the only enlisted rank that does not bear chevrons or rockers. Instead, the Specialist rank looks like a solid shield with an eagle centered on it. The Specialist has been trained in a military occupational specialty (MOS), his army job, and has some amount of experience in the service.
Corporal, CPL, E4 – The Corporal wears the insignia of two chevrons. The Corporal is the first rank in the US Army identified as a non-commissioned officer, or NCO. The Corporal and the Specialist both make the same amount of pay, but the Corporal outranks the Specialist because of his NCO status. Also, the Corporal is the first rank designated as a 'Junior non-commissioned officer', or Junior NCO.
Sergeant, SGT, E5 – The Sergeant wears the insignia of three chevrons. This rank is sometimes referred to as 'Buck Sergeant'. A Sergeant may serve as a squad leader in the absence of a Staff Sergeant. The Sergeant is a Junior NCO.
Staff Sergeant, SSG, E6 – The Staff Sergeant wears insignia of three chevrons and one rocker. The Staff Sergeant is generally placed in charge of one of the platoons four squads, but Staff Sergeants can also act as a Platoon Sergeant in the absence of a Sergeant First Class. The Staff Sergeant is a Junior NCO.
Sergeant First Class, SFC, E7 – The Sergeant First Class wears insignia of three chevrons and two rockers. The Sergeant First Class is the first rank designated as a Senior NCO. The ranks of E8 and E9 are also Senior NCO's.
Platoon Sergeant, PSG, E7 – The rank of the Platoon Sergeant is the same as the Sergeant First Class. There may be more than one Sergeant First Class in a platoon, but there is only one Platoon Sergeant. The Platoon Sergeant is the primary assistant and advisor to the Platoon Leader, who is usually a Lieutenant, and there before the Platoon Sergeant has authority over any other E7's in his platoon.
Master Sergeant, MSG, E8 – The Master Sergeant wears insignia of three chevrons and three rocker. The Master Sergeant works in a staff position, such as Operations.
First Sergeant, 1SG, E8 – The First Sergeant wears insignia of three chevrons and three rocker. A First Sergeant and Master Sergeant both earn equal pay, but the First Sergeant is the highest ranking enlisted soldier in a company, and therefore, has more authority than the Master Sergeant. A small diamond resides within the space of the chevrons and rockers.
Sergeant Major, SGM, E9 – The Sergeant Major wears insignia of three chevrons and three rocker. A small five pointed star resides within the space of the chevrons and rockers. Typically, the Sergeant Major is found in battle level or higher units.
Command Sergeant Major, CSM, E9 – A small five pointed star with a wreath resides within the space of the chevrons and rockers. The Command Sergeant Major is the senior enlisted adviser to the commanding officer. His duties carry certain ceremonial functions such as caring for the unit's colors, as well as serving as a monitor for, and advocate of, the enlisted men in the command.
Sergeant Major of the Army, SMA, E9 – The Sergeant Major of the Army is the highest enlisted rank. There is only one Sergeant Major of the Army at any one time. He represents all Army enlisted soldiers. The eagle from the Great Seal of the United States is centered between two five-pointed stars centered horizontally between the chevrons and rockers.
Each of the aforementioned ranks is special in its own way, and holds a valuable place in the military hierarchy. Although their ranks, duties and responsibilities may vary, soldiers serving at all level of the military order are equally as important as their fellow service members.