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]
Staff sergeant Staff sergeant (SSgt) is E-5 in the U.S. Air Force. It ranks above senior airman and below technical sergeant. It is the Air Force's first non-commissioned officer rank, as well as the first Air Force rank to which promotion is attained on a competitive basis. Sergeants, also known in Air Force jargon as "buck sergeant"', no longer exist, having been eliminated in the 1990s after sharing the same pay grade with that of the rank of senior airman (E-4). Staff sergeants are expected to be technically proficient and function as first-line supervisors within a 'work center'. After being selected for promotion, senior airmen must attend Airman Leadership School, which teaches them basic leadership skills and how to write performance reports to become staff sergeant. The term of address is "Staff Sergeant" or "Sergeant". High year of tenure was reduced from 20 to 15 years in 2013.