Armed guards are specially trained in the use of firearms and licensed to carry firearms during their shift. They must be of an even temperament and should have a good understanding of the conditions surrounding the property they are protecting. Armed guards generally make more money than unarmed guards -- for obvious reasons.
Armed guards should only be used in situations requiring protection of money, jewelry, art works, firearms, or other objects which might attract armed robbers. Protect the money which is exposed to the public by making frequent safe-drops, keeping cash register drawers shut whenever possible, and enforcing rigid money-handling procedures. Other valuables should be physically secured, if possible, before exposing them to the public.
For more information about security guards