3-22. Preparation consists of those activities performed by units and Soldiers to improve their ability to execute an operation (ADP 5-0). Preparation begins during planning with activities that are required to set conditions for the execution of operations such as information collection, movement of forces, terrain management, and sustainment preparation. These activities will continue after completion of the operation order brief to subordinate units with a confirmation brief, which is used to ensure subordinates the commander’s intent, the mission, and the concept of operations. Preparation activities also include rehearsals, which allow confirmation of a shared understanding as well as synchronization of operations prior to execution. The four types of rehearsals are the backbrief, the combined arms rehearsal, the support rehearsal, and the battle drill or standard operating procedures rehearsal.