Commonly used business transactions (e.g., purchase orderA document that is created by a buyer indicating t..., invoiceA detailed statement showing goods sold or shipped..., etc.) organized in a formal, structured manner consisting of a transactionA single completed transmission, e.g., transmissio... setSee Secure Electronic Transaction. header control segment, one or more data segments, and a transaction set trailerThe part of the truck that carries the goods. control data segment.