purchase order: A purchase order (PO) is a commercial document issued by a buyer to a seller, indicating types, quantities, and agreed prices for products or services the seller will provide to the buyer. Sending a PO to a supplier constitutes a legal offer to buy products or services.(a document that allowes you to buy something)
delivery note : A document that accompanies a goods shipment and lists details about the goods delivered. A delivery note explains what the contents of a package are. If some goods that were ordered are not enclosed (due to lack of stock, unavailability, etc.) they will also be listed on the delivery note.(the paper work that comes with the delivery. you will usually get 2 copies, also makes sure you havre been delivered all the products that you wanted.
goods recived note: Record of goods received at the point of receipt. This record is used to confirm all goods have been received and often compared to a purchase order before payment is issued
Invoice: a list of goods sent or services provided, with a statement of the sum due for these; a bill.(an invoice…