"PO" can refer to several concepts, but one common meaning is "Purchase Order." A Purchase Order is a document issued by a buyer to a seller, indicating the details of products or services they wish to purchase. It typically includes information such as quantities, prices, and delivery dates, serving as a formal agreement between both parties. Another meaning of "PO" is "Post Office," which is a public department responsible for mail services. The Post Office handles the collection, processing, and delivery of letters and packages, ensuring that communication and goods can be sent and received efficiently across different locations.