Key concepts

If you are new to electronic invoicing and procurement and the exchange of standardized business documents, these pages explain the key concepts used in the API:

• Business participant identifiers: how senders and receivers are identified.
• Message envelope identifier: how a message is identified.
• Message flow: the statuses a message goes through.
• Business transaction groups and business profiles: which documents are exchanged, and under which agreements.
• Services: additional processing of a message.
• Unit of measure: the unit codes used on document lines.
• Working with MLRs, eMLRs and MLAs: responses and actions, including tax reporting.
• Response codes: the HTTP status codes the API returns.