List of unrelated alpha-2 codes in ISO 639 and ISO 3166
Below is a list of 2 letter codes that are contained in ISO 639-1 and ISO 3166-1 alpha-2 but the language they encode has no relation to the country. Theoretically, country and language codes are orthogonal so a real conflict does not exist, but practically, it could be a source of confusion.
E.g. one sees a subdomain be.example.org, it is unclear whether be refers to Belarusian language or to Belgium. Or one sees uk.example.org, which could refer to Ukrainian language or to the United Kingdom.