UN/EDIFACT
UN/EDIFACT is the international EDI (Electronic Data Interchange) standard maintained by the UN Centre for Trade Facilitation and Electronic Business (UN/CEFACT). It defines syntax and message structures for thousands of business-to-business and business-to-government transactions, with particular dominance in maritime shipping, customs, and freight forwarding worldwide.
UN/EDIFACT messages follow a hierarchical structure of segments (e.g., NAD = Name and Address), composite data elements, and simple data elements. Each message type has a 6-letter identifier (e.g., CUSCAR for customs cargo report, BAPLIE for bay plan, COPRAR for container pre-arrival, IFTMIN for transport instruction).
EDIFACT is the lingua franca of ocean freight. It predates JSON and modern APIs but remains universal because every port community system, shipping line, and customs authority speaks it.