An Operation Order, often abbreviated to OPORD, is a plan format meant to assist subordinate units with the conduct of military operations. An OPORD describes the situation the unit faces, the mission of the unit, and what supporting activities the unit will conduct in order to achieve their commander's desired end state. Normally an OPORD is generated at the battalion, regimental, brigade, divisional, or corps headquarters and disseminated to its assigned or attached elements.
https://en.wikipedia.org/wiki/Operations_order