An is a directive issued by a commander to subordinate commanders for the purpose of effecting the coordinated execution of an operation. They are issued to direct the execution of long-term operations as well as the execution of discrete short term operations.

Operation order          

Explanation:

An operation order is a directive issued by a commander to subordinate commanders for the purpose of effecting the coordinated execution of an operation. They are issued to direct the execution of long-term operations as well as the execution of discrete short term operations.  It is an order issued by the commander to bring about the execution of project and it is usually written. The operational order is divided into situation, mission, execution, sustainment, and command and control. Other orders given by the military are warning order and fragmentary order.

when the united states took over