Language code schemes attempt to classify within the complex world of human languages, dialects, and variants. Most schemes make some compromises between being general enough to be useful and complete enough to support specific dialects.
For example, most people in Central America and South America speak Spanish. Spanish spoken in Mexico will be slightly different from Spanish spoken in Peru. 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 idioms.
| Scheme |
Notes |
Examples |
| Codes for English |
Codes for Spanish |
| ISO 639 |
The original ISO standard from 1967 to 2002. Now obsolete, it was replaced by ISO 639-1, ISO 639-2, and ISO 639-3. Sometimes used as a shorthand for the union of all 639 standard codes. |
- en – two-letter code
- eng – three-letter code
- enm – Middle English, ca. 1100–1500
- ang – Old English, ca. 450–1100
- cpe – other English-based creoles and pidgins
- EN – English or American two-letter capital code
(source: W3C[1])
|
- esl – three-letter code
- spa – alternative three-letter code
- ES – Spanish two-letter capital code
|
| ISO 639-1 |
Two-letter code system made official in 2002, containing 136 codes. Many systems use two-letter ISO 639-1 codes supplemented by three-letter ISO 639-2 codes when no two-letter code is applicable. |
(from List of ISO_639-1 codes)
|
|
| ISO 639-2 |
Three-letter system of 464 codes. |
- eng – three-letter code
- enm – Middle English, ca. 1100–1500
- ang – Old English, ca. 450–1100
- cpe – other English-based creoles and pidgins
(from List of ISO 639-2 codes)
|
|
| ISO 639-3 |
An extension of ISO 639-2 to cover all known, living or dead, spoken or written languages in 7,589 entries. |
- eng – three-letter code
- enm – Middle English, ca. 1100–1500
- aig – Antigua and Barbuda Creole English
- ang – Old English, ca. 450–1100
- svc – Vincentian Creole English
- others
(from List of ISO 639-3 codes)
|
- spa – Spanish
- spq – Spanish, Loreto-Ucayali
- ssp – Spanish sign language
- others
|
| Old SIL codes |
Codes created for use in the Ethnologue, a publication of SIL International that lists language statistics. The publication now uses ISO 639-3 codes. |
|
SPN |
| IETF language tag |
An IETF best practice, currently specified by RFC 4646 and RFC 4647, for language tags easy to parse by computer. The tag system is extensible to region, dialect, and private designations. |
- en – English, as shortest ISO 639 code.
- en-US – English as used in the United States (US is the ISO 3166-1 country code for the United States)
- en-US-x-fandom – English with private subtag
(source: IETF memo[2])
|
- es – Spanish, as shortest ISO 639 code.
- es-419 – Spanish appropriate for the Latin America and Caribbean region, using the UN region code
|
| Verbix Language Codes |
Constructed codes starting with old SIL codes and adding more information.[3] |
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