Promotion

• Commissioned officers get their authority by a commission from the president of the United States, hence the name. NCOs are promoted from within the enlisted ranks--corporals by the company commander, sergeants by promotion boards made up of commissioned officers.
  
  

Training and Experience

• Commissioned officers are generally college-trained and receive their commission upon entering active service. NCOs work their way up from private by demonstrating ability and leadership qualities.
  
  

Authority

• NCOs serve as leaders and supervisors of the soldiers directly under them. Only officers can be unit commanders. Officers give the orders; NCOs carry them out.
  
  

Protocols

• Non-commissioned officers do not receive salutes from lower ranks. Commissioned officers are saluted.
  
  

Ranks

• In the U.S. Army, all ranks from corporal to warrant officer (WO1) are non-commissioned officers. Ranks of chief warrant officer (CW2) and above are commissioned.