Ok, here's the long answer: In the US military, the authority to command the armed forces is vested in the President. Since it is impossible for the Prez to be everywhere to oversee everything in the name of the American people, an officer is appointed to act in the President's place. This officer is granted a commission from the President. This means that he speaks with the President's voice and acts with the President's authority in the military matters assigned to the officer. These commissioned officers have broad powers, duties, and responsibilities within their military branch. To assist the commissioned officers, other officers are appointed. These officers are not granted a commission from the President to speak and act in his name. They are called non-commissioned officers. They only have the authority to act in the specific areas granted to them by the officers they support. A NCO working for the personnel officer has no authority to tell an enlisted man in the supply room how to do his job, for example. The best way to show this is to look at military training. Commissioned officers are responsible for drafting training plans, arranging for whatever supplies are needed (food, fuel, bullets, vehicles, etc), scheduling the use of training sites, setting the training schedule, defining the training tasks, conditions, and standards. Non-commissioned officers advise the commissioned officers on training issues (what training is needed, what is needed to make training better, etc) and actually conduct the training.

a commissioned officer is like a lieutenant, captain, etc.. a non commissioned officer is anything above the enlisted rank of e-4, so sgt and above is considered a non commissioned officer. There job depends on what kind of unit they are in and what there MOS is.

Is a Corporal a Non-Commissioned Officer? I have been surprised by several answers to the question “Is a corporal a non-commissioned officer?”, saying that a corporal is not an officer. I have been even more surprised to discover that some of these answers have been made by members of the Fighting Services. In a effort to keep this brief, I will try to avoid both the Naval Service and the Aviation Service, and limit my comments mainly to the Military Service, as I do not wish to discuss the Naval Service’s police-corporal, ship-corporal, commissioned officers, ordinary officers, warrant officers, subordinate officers, petty officers, substantive-rates, and non-substantive rates. In other words: sailors no, soldiers yes, flyers no Obviously there is no such thing as a non-commissioned officer. The phrase “Non-Commissioned Officer” taken on its’ own is gobbledy-gook. A corporal is an officer. No one can hold authority as an officer without a commission. A corporal holds a commission. Therefore a corporal is a commissioned officer, usually referred to as a “Non-Commissioned Officer”. There are many occupations, besides the Military Service, that use phrases which, separated out on their own, clearly make no sense. Those members of the Fighting Services who have made such silly answers about corporals should immediately review their Articles-of-War, and I suggest, their articles-of-common-sense. An officer is a lord, or gentleman, or man, who holds no authority of his own. An officer is a lord, or gentleman, or man, who as an inferior, is given a rank of an officer over other ranks, which rank holds the complete authority or partial authority of his superior who has given such authority to such inferior, either in writing, or on the understanding that it will be given in writing as soon as possible. Such writing is usually referred to as a “commission”, and on some rare occasions as a “warrant”. In case of the Military Service, any rank in the presence of the enemy, who disobeys a verbal order given by a soldier of higher rank who is also an officer, such officer being present, makes himself liable to capital punishment according to the Articles of War. Accordingly, a corporal is far more likely to be an “officer” than a general is likely to be an “officer”. But I won’t argue the point, and for the moment I will accept that both a corporal-check and a lieutenant-general are officers. Whether a spiritual lord (bishop) or a temporal lord (peer), Military Service rank always takes precedence over a temporal lord’s (peer’s) rank or spiritual lord’s (bishop’s) rank whilst such lord is in the Military Service. A bishop or arch-bishop is a lord, but is not a peer. At this stage there will be no further discussion of bishops or arch-bishops, as not only are they illegal in calvinist countries, but in many non-calvinist countries where they have always been legal, nevertheless bishops and arch-bishops are no longer part of the civil government or even civil state. A peer is not an officer because he holds his own authority, and therefore commands his own inferiors, or his own soldiers, or his own forces, on his own authority, not on someone else’s authority. Exactly the same apples to a knight. Of course both a peer and a knight are appointed by patent (letter-patent) which is the same as an officer appointed by commission. So what is the difference between a patent and a commission? The difference is that the superior giving any commission, including a commission under the written Articles of War, can bring an officer’s commission to an end under strictly laid down written conditions, almost invariably only by a court-martial. A superior giving a patent to a peer or knight, gives that patent forever, because the superior can never bring the patent he has granted to his inferior to an end. A patent (letter-patent) is forever. Of course these days patents (letter-patents) are usually given by governments for useful inventions and products, not for lordships or knighthoods. Of course a knight’s patent (letter-patent) comes to an end when he dies, because a knighthood cannot be inherited. The point is that the superior can never take back a knighthood’s patent (letter-patent) granted to his inferior. A dame is simply the lady (wife) of a knight, and therefore can never inherit a knighthood. A lord’s (peer’s) patent (letter-patent) does not come to an end when he dies, or in rare cases if it’s a lady (peeress) when she dies, but often does because there is no one to inherit the peership, or the peeress-ship in those rare cases. It is only in the Royal Family that females have the absolute right to inherit the Queen-Regnant, because just as kings are not peers, so queen-regnants are not peeresses. However in almost all peerage families, the patent strictly lays down that the peerage can only be inherited by “male issue”, meaning a natural-born and legally-born male child. That means that there is a high probability that the family will lose the peerage. Of course those peerage families that existed before 1199, I believe there is only one such family, and those very few peerage families where the patent lays down “general issue”, are allowed to have female inheritance. Obviously “general issue” means any natural-born and legally-born child. But this is pretty meaningless, because unlike sons where the oldest son always inherits, the oldest daughter can never inherit, because all daughters must inherit equally. Clearly you must split the land between females, but you can’t split a peerage title, so the peerage must lapse. So it is only those very rare occasions where upon the death of the lord (peer) or lady (peeress) and there is only one daughter, that those very few peerages of “general issue” can ever be inherited by a female. The term “corporal” means an officer in charge of a corps. In the Military Service the size of a corps has changed over the centuries, ranging from 1000 men to 60000 men. The term “corporal” means an officer NOT in charge of a corps in the Military Service. Over the centuries the numbers of men a corporal-check has held command over have varied from three to sixty. But never a 1000 men, let alone 60000 men. In recent times a corporal-check commissioned officer is unknown, except for a few instances where the leader of a country has made his entire cavalry regimental body-guard, or horse-guards, all commissioned officers. A “commissioned officer” in the Military Service (not Naval Service or Aviation Service) means: King’s Commissioned Officer Queen’s Commissioned Officer Parliamentary Commissioned Officer Speaker’s Commissioned Officer Governor-General’s Commissioned Officer Governor’s Commissioned Officer Viceroy’s Commissioned Officer Congressional Commissioned Officer President’s Commissioned Officer Chief-Executive’s Commissioned Officer A commissioned officer always holds his rank no matter as to how many different regiments he is transfered to throughout his service in the Military Service (or army). In effect a commissioned officer has not only regimental rank, but also Military Service (or army) rank. That is why all field marshals or generals always have to hold the rank of Colonel-Horse, or Colonel-Foot, or Colonel-Array, or Colonel-Commandant, in their own regiment, as there is no such thing as a regiment of generals or field-marshals. A “non-commissioned officer” in the Military Service (not Naval Service or Aviation Service) means: Colonel-Commandant’s Commissioned Officer Colonel-Horse’s Commissioned Officer Colonel-Foot’s Commissioned Officer Lieutenant-Colonel’s Commissioned Officer A non-commissioned officer does not hold any rank in his particular Military Service (or army). He only holds rank in his own regiment, and therefore loses his non-commissioned officer rank if he ever transfers to another regiment, and immediately becomes a private-man (or common-man, common-soldier, private-gentleman, private-soldier, private-rank, private-sentinel, private-piquet, private-vedette, horse-guard, dragoon, lancer, trooper, foot-guard, fusilier, carabineer, ranger, rifleman, parachutist, marine, maxim, matross). The fact that he is almost invariably in his new regiment within 24 hours promoted back up to his previous non-commissioned rank in his old regiment is irrelevant. He had to lose his non-commissioned officer rank and become a private-man rank upon his transfer to his new regiment, if only for a few hours. The private-man and the commissioned officer are both the same, in the sense that they both keep their rank when they transfer to another regiment. Talking about ranks, it might be useful to list the basic ones over the centuries: Common-Man (or Common-Soldier) Corporal-Check Cornet (or Guidon, Ensign, Partizan, Sub-Lieutenant) Lieutenant-Horse (or Lieutenant-Foot) Captain-Horse (or Captain-Foot) Captain-Major (or Corporal-Major) Lieutenant-Colonel Colonel-Horse (or Colonel-Foot) Corporal-Field (or Corporal-General, Brigadier-General) Corporal-Major-General & Field-Marshal (or Major-General) Lieutenant-General & Field-Marshal (or Lieutenant-General) Captain-General & Field-Marshal (or Captain-General) As you can see, there used to be only one private-man or common-man rank: Common-Man And there used to be only one non-commissioned officer rank: Corporal-Check Although the rank of corporal-check is common in infantry regiments, it is only in english speaking countries that it is common in both infantry and cavalry, or armor regiments. Most other countries use a different name for the rank in non-infantry regiments, such as: Brigadier-Check Bombardier-Check As a matter of interest, during World War I, the following terms were adopted to clarify officer authority and officer rank: Section Commander Corporal-Check Platoon Commander Sergeant-Foot, Ensign, Partizan, Sub-Lieutenant, Second-Lieutenant Company Commander Captain-Foot Officer Commanding Lieutenant-Colonel General Officer Commanding Major-General, Lieutenant-General General Officer Commanding in Chief Captain-General, Field-Marshal artillery sub-brigades (exactly the same as regiments) used: Detachment Commander Bombardier-Check Troop Commander Conductor-Array, Sergeant-Array, Second-Lieutenant Battery Commander Captain-Array Officer-Commanding Lieutenant-Colonel cavalry regiments or armor regiments used: Patrol Commander, Vehicle Commander Corporal-Check Troop Leader (the term “Troop Commander” has already been used above) Corporal-Horse, Sergeant-Horse, Sergeant-Array, Cornet, Guidon Squadron Leader (why “Squadron Commander” is not used is not known) Captain-Horse, Captain-Array Officer Commanding Lieutenant-Colonel In the present day Military Service there are a few more ranks than those already mentioned above, but I just want to concentrate on one peculiar one: the lance-corporal The lance-corporal is an officer but, is not an officer rank, is not a non-commissioned officer, and is not a commissioned officer. A lance-corporal is in fact a private-man drawing the same pay and holding the same officer authority or commander authority as a corporal-check. However he is not a Colonel’s Commissioned Officer, he is a Colonel’s Temporary Appointed Officer. Therefore a lance-corporal can be demoted for no reason whatsoever by the Lieutenant-Colonel, and no court-martial is required, and neither is any allegation of inefficiency or impropriety required. I hope the above may be of some interest to those enquiring into the most important and most powerful officer rank ever created in the Military Service, or more accurately, the Non-Military Service officer rank of Non-Commissioned Officer rank created in the regiments of the Military Service: the CORPORAL!