Officer

An Officer is a member of an armed force who holds a position of authority. These are usually defined as groups of ranks.

There are two main types of Officer:
 * A Commissioned Officer holds a Commission charging them with the duties and responsibilities of a specific office or position. They are authorised to be in command of a military unit, and totally responsible for its strategy and welfare. They act as management, and are usually required to hold (or earn) a university degree.
 * A Non-Commissioned Officer is an Enlisted force member who holds a position of authority, from promotion within non-officer ranks. They act usually as supervisors or team leaders, can be in charge of a unit (not in command)

There are other types of Officers within these:
 * A General Officer or Flag Officer refers to the most senior commissioned officers, usually above OF-6 (Brigadier General or Read Admiral)
 * A Field Officer refers to the middle commissioned officers, typically from Major to Colonel (or Brigadier)
 * A Company Officer or Junior Officer refers to the lowest commissioned officers, up to Captain or a naval Lieutenant
 * A Subordinate Officer is an officer that has not yet completed training and received their Commission. In the Royal Navy, they hold their ranks by Admiralty Board orders. These include Cadet, Midshipman or Acting Sub-Lieutenant (RNR); and in the Royal Marines, Second Lieutenant
 * A Warrant Officer is a senior Non-Commissioned Officer, however they are often regarded as a class of their own between commissioned and non-commissioned

Commissioned officers derive authority directly from a sovereign power and, as such, hold a commission charging them with the duties and responsibilities of a specific office or position. Commissioned officers are typically the only persons, in a military environment, able to act as the commanding officer (according to the most technical definition of the word) of a military unit.

Non-commissioned officers (NCOs) in positions of authority can be said to have control or charge rather than command per se, although the use of the word "command" to describe any use of authority is widespread and often official.

Having officers is one requirement for combatant status under the laws of war, though these officers need not have obtained an official commission or warrant. In such case, those persons holding offices of responsibility within the organization are deemed to be the officers, and the presence of these officers connotes a level of organization sufficient to designate a group as being combatant.