These codes may be used to organize library collections or presentations of data, to choose the correct localizations and translations in computing, and as a shorthand designation for longer forms of language names.
Most schemes make some compromises between being general and being complete enough to support specific dialects.
Different regions of Mexico will have slightly different dialects and accents of Spanish.
A language code scheme might group these all as "Spanish" for choosing a keyboard layout, most as "Spanish" for general usage, or separate each dialect to allow region-specific variation.
See: List of ISO 639 language codes See: List of ISO 639-2 codes See: List of ISO 639-3 codes Navigate also the hierarchy of the Linguasphere Register code-system published online by hortensj-garden.org [4] Within hierarchy of Linguasphere Register code-system: Compare: 52-ABA-a Scots + Northumbrian outer unit & 52-ABA-b "Anglo-English" outer unit (= South Great Britain traditional varieties + Old Anglo-Irish) Within hierarchy of Linguasphere Register code-system: Compare: 51-AAA-a Português + Galego outer unit & 51-AAA-c Astur + Leonés outer unit, etc.