Standards/MARC Standards MARC 21 [62] is an implementation of the American national standard, Information Interchange Format (ANSI Z39.2) and its international counterpart, Format for Information Exchange (ISO 2709). These standards specify the requirements for a generalized interchange format that will accommodate data describing all forms of materials susceptible to bibliographic description, as well as related information such as authority, classification, community information, and holdings data. The standards present a generalized structure for records, but do not specify the content of the record and do not, in general, assign meaning to tags, indicators, or data element identifiers. Specification of these elements are provided by particular implementations of the standards. The MARC formats are defined for five type of data, in particular for data listed below: The MARC 21 formats are communication formats, primarily designed to provide specifications for the exchange of bibliographic and related information between systems. They are widely used in a variety of exchange and processing environments. As communication formats, they do not consent internal storage or display formats to be used by individual systems.