A reservation is a request to the warehouse to allocate a product for future orders. The purpose of a reservation is to ensure that a product is available when ordered. There are two types of reservations: reserve now and future receipt. Reserve now reservations are used to immediately allocate inventory, whereas future receipt reservations are used to allocate inventory when a specific open purchase order is received or when inventory is manually allocated in Future Receipt Reservation Allocate. When inventory is allocated for a future receipt reservation, a reserve now reservation is automatically created.