Recommended practice is to use either a non-literal value representing a language from a controlled vocabulary such as ISO 639-2 or ISO 639-3, or a literal value consisting of an IETF Best Current Practice 47 [[IETF-BCP47](https://tools.ietf.org/html/bcp47)] language tag. (en)
A [second property](/specifications/dublin-core/dcmi-terms/#http://purl.org/dc/terms/language) with the same name as this property has been declared in the [dcterms: namespace](http://purl.org/dc/terms/). See the Introduction to the document [DCMI Metadata Terms](/specifications/dublin-core/dcmi-terms/) for an explanation. (en)