The U.S. Army has many ranks, from private to four-star general, but they generally fall into three categories: enlisted ranks, officers and warrant officers. Each group is divided into pay grades that run from 1 to 4, 9 or 10.
The lowest rank in the army is that of private. This is the rank most new recruits are assigned on entering basic training. The private's duty is to carry out lawful orders from superiors. Privates are classed as E-1 for administrative purposes. The army recognizes three grades of private: PV, PV2 and PFC. Above the PFC, specialists are soldiers with special certifications, usually for operating systems and equipment.
Above the E-4 specialists are the non-commissioned officers, or NCOs, beginning with the rank of corporal. Corporals act as leaders for small units under the direction of sergeants. The Army has at least six grades of sergeant, terminating with the Command Sergeant Major of the Army.
Officer ranks run from second and first lieutenants to captains, majors and lieutenant colonels. Above the rank of colonel are the general officers who range from one to four stars. In wartime, some four-star generals can become five-star generals of the army. Intermediate between NCOs and officers are warrant officers. Usually pilots and other specialists, the four grades of warrant officers are largely outside the chain of command and focus on a specialized skill set.