The X12 format, designed and maintained by the American National Standards Institute (ANSI), provides standard data formats that enable the exchange of business documents between trading partners. Different industries use different data formats or transaction types for different purposes. Common to all, however, is a three-digit numerical designation, which identifies these different transactions; for example, an 834 Benefit Enrollment and Maintenance transaction.
The standard defines a hierarchy of levels—Interchange, Group and Transaction control segments—and specifies both the syntax and semantics of messages. For example, a field designated as quantity might be syntactically specified as required or optional, and the minimum and maximum size of the field might be syntactically defined as well.
