When it comes to running a business, there are three primary documents that play an important role in the lifecycle of a product or service: sales orders, purchase orders, and invoices. These documents are integral to tracking transactions and they need to be handled correctly to ensure accurate record keeping and successful operations.

Sales Orders refer to documentation used by merchants to confirm and document the sale of goods or services to customers. This document usually contains information about the customer and the item purchased.

Purchase Orders (PO) are documents a merchant generates to indicate their intent to buy goods or services from another party. This document generally contains information about the vendor, the goods or services sold, and price.

Invoices serve as proof of payment for a given transaction and often contain details about both the buyer and seller, such as contact and shipping info. It also typically includes applicable taxes and fees.