The purchaser’s authorization used to formalize a purchase transaction with a supplier. The physical form or electronic transaction a buyer uses when placing order for merchandise. 2. Common grouping of orders for goods/services. Several SKU categories may be listed on one purchase order. Most customers group their orders in a particular way to facilitate distribution at the other end. For example, one purchase order for an apparel importer might encompass 2 dozen green sweaters and 2 dozen red sweaters. If those P.O.s originated from the same store, it is simple for the store to put all items under that P.O. onto the right truck.