For some languages, it is sometimes useful to distinguish between variants spoken in different countries, e.g. when you want to distinguish speech synthesis for Belgian Dutch or Dutch from the Netherlands. What you'll need initially is just the list of ISO 639-1 language tags (two-letter codes), since the biggest languages are all representedFor the lists of language tags, you need to check ISO 639-1 (for languages that have a two-letter code), ISO 639-3 (for languages that don't have a two-letter code but only a three letter code) and then either the relevant country codes (e.g. for en-US versus en-GB) or ISO 15924 for the writing systems tags (e.g. for zh-Hans versus zh-Hant).
The ISO 639 is International Organization Standard for language codes which are used to establish internationally recognized codes for representation of languages. ISO Burmese Language codes may be two letter codes or three letter codes. The ISO language codes were approved in 1967. ISO Burmese Language codes are : ISO 639-1 code, ISO 639-2
ISO Persian Language codes may be two letter codes or three letter codes. The ISO language codes were approved in 1967. ISO Persian Language codes are : ISO 639-1 code, ISO 639-2 code and ISO-3 code. ISO 639-2 is alpha-3 code and ISO 639-1 is the alpha-2 code. The ISO 639-2 code is divided into Bibliographic(B) and Terminological(T) codes which 0acD8U.