what is the difference between an officer and a non commissioned member
Non-commissioned officer A non-commissioned officer or noncommissioned officer (NCO, colloquially non-com or noncom) is a military officer who has not earned a commission.[1][2][3] Such is also called sub-officer in some countries. Non-commissioned officers, in the English-speaking world, usually obtain their position of authority by promotion through the enlisted ranks.[4] In contrast, commissioned officers hold higher ranks than NCOs, have more legal responsibilities, are paid more, and often have more non-military training such as a university diploma. Commissioned officers usually earn their commissions without having risen through the enlisted ranks. "Mustang" is a slang term in the United States Armed Forces used to refer to a commissioned officer who began his or her career as an enlisted service member.[citation needed]
Warrant officer Warrant officers in the United States are classified as officers and are in the "W" category (NATO "WO"); they are technical leaders and specialists. Chief warrant officers are commissioned by the President of the United States and take the same oath as regular commissioned officers. They may be technical experts with a long service as enlisted personnel, or direct entrants, notably for U.S. Army helicopter pilots.