ISO 25964-1:2011 gives recommendations for the development and maintenance of thesauri intended for information retrieval applications. It is applicable to vocabularies used for retrieving information about all types of information resources, irrespective of the media used (text, sound, still or moving image, physical object or multimedia) including knowledge bases and portals, bibliographic databases, text, museum or multimedia collections, and the items within them. ISO 25964-1:2011 also provides a data model and recommended format for the import and export of thesaurus data.ISO 25964-1:2011 is applicable to monolingual and multilingual thesauri. ISO 25964-1:2011 is not applicable to the preparation of back-of-the-book indexes, although many of its recommendations could be useful for that purpose. ISO 25964-1:2011 is not applicable to the databases or software used directly in search or indexing applications, but does anticipate the needs of such applications among its recommendations for thesaurus management.