The transfer of data between two or more companies, using networks and the Internet. EDI is an increasingly important and easy mechanism used by companies to buy, sell, and trade information. A standard format for exchanging business data, EDI saves messages as a string of data elements, each of which represents a singular fact (such as price or product model number). The parties who exchange EDI transmissions are called trading partners. ANSI approved a set of EDI standards known as the "X12 standards."