<P> The rank was first used in the 13th century in the Royal Navy and is today used in most services in many countries, including the Commonwealth nations and the United States . </P> <P> Outside the United States, warrant officers are included in the "Other Ranks" (OR) category, equivalent to the US "E" (Enlisted) category and rank between non-commissioned officers and commissioned officers . The warrant officers in Commonwealth navies rank between chief petty officer and sub-lieutenant, in Commonwealth air forces between flight sergeant and pilot officer, and in Commonwealth armies between staff sergeant and second - lieutenant . </P> <P> 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 . </P> <P> The warrant officer corps began in the nascent Royal Navy . At that time, noblemen with military experience took command of the new navy, adopting the military ranks of lieutenant and captain . These officers often had no knowledge of life on board a ship--let alone how to navigate such a vessel--and relied on the expertise of the ship's master and other seamen who tended to the technical aspects of running the ship . As cannon came into use, the officers also required gunnery experts; specialist gunners began to appear in the 16th century and also had warrant officer status . Literacy was one thing that most warrant officers had in common, and this distinguished them from the common seamen: according to the Admiralty regulations, "no person shall be appointed to any station in which he is to have charge of stores, unless he can read and write, and is sufficiently skilled in arithmetic to keep an account of them correctly". Since all warrant officers had responsibility for stores, this was enough to debar the illiterate . </P>

What is a warrent officer in the army
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