types:
desk officer
a military officer who is not assigned to active duty
bombardier
a noncommissioned officer in the British artillery
corporal
a noncommissioned officer in the Army or Air Force or Marines
lance corporal
an enlisted man in the marine corps ranking above a private first class and below a corporal
line officer
a commissioned officer with combat units (not a staff officer or a supply officer)
P.O.,
PO,
petty officer
a noncommissioned officer in the Navy or Coast Guard with a rank comparable to sergeant in the Army
quartermaster
an army officer who provides clothing and subsistence for troops
ranker
a commissioned officer who has been promoted from enlisted status
sergeant
any of several noncommissioned officer ranks in the Army or Air Force or Marines ranking above a corporal
staff officer
a commissioned officer assigned to a military commander's staff