EDI (Electronic Data Interchange) allows companies to exchange structured business data electronically between computer systems. It facilitates quick and easy transmission of common business documents like purchase orders, invoices, shipping notices between trading partners, typically a supplier and customer. EDI uses standardized formats to convert documents so they can be exchanged and processed electronically without manual re-entry of data. The two main EDI standards are EDIFACT, the international generic standard developed by the UN, and ANSI ASC X12, the US national standard.