ISO 639-4:2010给出了使用ISO 639其他部分中规定的代码及其与其他代码的组合进行语言编码的一般原则。它还规定了ISO 639各部分组合使用的指南。 ISO 639-4的术语和一般说明旨在取代ISO 639其他部分的相应文本，以供将来修订时参考。 给出了描述语言实体的相关元数据，作为支持ISO 639系列的语言数据数据库的框架。

ISO 639-4:2010 gives the general principles of language coding using the codes that are specified in the other parts of ISO 639 and their combination with other codes. It also lays down guidelines for the use of any combination of the parts of ISO 639. The terminology and general descriptions of ISO 639-4 are intended to replace corresponding text of other parts of ISO 639 as relevant in future revisions. Relevant metadata for the description of linguistic entities are given, as a framework for databases of linguistic data to support the ISO 639 series.