Halliday

The language code refers to the ISO-639-2 and ISO-639-3 codes.

• en (english)
• fr (french)

The language code may be followed by a hyphen and a country code, a country variant or a script:

• zh-CN
• zh-Hant
• fa-Latn (Persian written in Latin letters, a romanization)

A name in Latin letters of a language that is written in another script gets -Latn after the language code (fa-Latn, ar-Latn, ru-Latn, zh-Latn ...). The plain code (fa, ar, ru, zh ...) is for the names in the language's own script.

Accepted pseudo language codes:

• post (postal codes)
• icao, iata, faac, tcid (airport codes)
• abbr (abbreviation)
• link (link to website)
• phon (phonetics)
• piny (pinyin)
• wkdt (wikidataid)
• unlc (UNLOCODE)
• nuts (EU NUTS code)
• lauc (EU LAU code)

• p. = preferred
• s. = short
• h. = historical
• c. = colloquial