ENLISTED RANK

An 'enlisted rank' in the Military of the United States is generally any rating below that of a commissioned officer. The term can be inclusive of non-commissioned officers or NCO for short. In its most exclusive sense, the term applies only to the lowest ranks of military service. Though it is the lowest of the ranks, it is the most important. The lower-enlisted (in the United States Army, E-4 and below) are the core of the working force, while the NCO corps (in the United States Army, E-5 and above) provides the direct leadership and training to these soldiers. The United States Coast Guard uses the same enlisted rank structure as the US Navy.
In the British Armed Forces and the armed forces of other Commonwealth countries (except Canada), the equivalent term in respect of armies and air forces is Other Rank (or OR for short), while navies use the term rating; in Canada, the term is non-commissioned member (NCM).