Paygrade	Abbreviation	Rank
O-11	GA	General of the Army (wartime only)
O-10	GEN	General
O-9	LTG	Lieutenant General
O-8	MG	Major General
O-7	BG	Brigadier General
O-6	COL	Colonel
O-5	LTC	Lieutenant Colonel
O-4	MAJ	Major
O-3	CPT	Captain
O-2	1LT	First Lieutenant
O-1	2LT	Second Lieutenant

This chart represents the U.S. Army officer rank insignia.

The highest Army rank, known as General of the Armies, is traditionally considered the equivalent of a six star general. No insignia has ever been authorized for the rank, and it has only been held by two people in history: John J. Pershing and George Washington (very posthumously).

The structure of U.S. ranks has its roots in British military traditions. At the start of the American War of Independence, uniforms, let alone insignia, were barely affordable and recognition of ranks in the field was problematic. To solve this, Gen. George Washington wrote:

"As the Continental Army has unfortunately no uniforms, and consequently many inconveniences must arise from not being able to distinguish the commissioned officers from the privates, it is desired that some badge of distinction be immediately provided; for instance that the field officers may have red or pink colored cockades in their hats, the captains yellow or buff, and the subalterns green."

From 1780, regulations prescribed two stars for major generals and one star for brigadier generals worn on shoulder boards, or epaulettes.

The period of 1821 to 1832 witnessed a brief period of using chevrons to identify officer grades, a practice that is still observed at West Point for cadet officers.

Colonels received their eagle in 1832, and four years later lieutenant colonels were using oak leaves and captains and first lieutenants their respective double and single bars. Both majors and second lieutnenants had no specific insignia. A major would have been recognizable as he would have worn the more elaborate epaulette fringes of a senior field officer but without insignia. The colour of insignia was gold on silver epaulettes in the infantry and vice versa in the other branches until 1851 when insignia became universally silver on gold for senior officers and gold for the bars of captains and first lieutentants.

From 1872 the majors received oak leafs in gold to distinguish them from the silver of lieutenant colonels and the bars of both captains and lieutenants became silver. In a similar fashion, 1917 saw the introduction of a single gold bar for second lieutenants. These changes created the curious situation (in terms of heraldic tradition) of silver outranking gold.

The Civil War saw the development of distinctive rank insignia in the Confederate armies. Junior officers up to captain had a less elaborate pattern of braid on their tunic cuffs and wore collar insignia of three horizontal bars for a captain, two for a first lieutentant and one for a second lieutenant. Majors, lieutentant colonels, and colonels wore repectively one, two, and three stars on the collar, and all grades of general had the insignia of three stars (the middle being slightly larger) in an open top wreath pattern.