ISO 639-2 (Codes for the representation of names of languages--Part 2: alpha-3 code) was based on the MARC Code List for Languages and published in 1998.  In the 22 cases where the ISO 639-2 list has two alternative codes, the bibliographic code is the same as the MARC code.  Language names in ISO 639-2 are not necessarily the same as those in MARC, particularly because of the practice of correlating the MARC language names with those used in Library of Congress Subject Headings.  The MARC list includes references for unused forms of language names, while the ISO list has in some cases included alternative name forms, but many are lacking, since this practice of supplying alternate forms has only recently been implemented.  In addition the MARC documentation includes a list of individual languages under collective codes or language groups, while the ISO list only includes the group codes themselves.  The Library of Congress is maintenance agency for both lists, and the two are kept compatible in terms of code additions and deletions.

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Introduction

MARC Code List for Languages:  Contents