Media type reflects the general type of intermediation device required to view, play, run, etc., the content of a resource. Used as an alternative to or in addition to the coded expression of Media type in field 007/00 (Category of material). Field 337 information enables indication of more specific media types and media types from various lists.
Multiple media types from the same source vocabulary or code list may be recorded in the same field in separate occurrences of subfield $a (Media type term) and subfield $b (Media type code). Terms from different source vocabularies are recorded in separate occurrences of the field.