The format for the culture name based on RFC 4646 is languagecode2-country/regioncode2, where languagecode2 is the two-letter language code and country/regioncode2 is the two-letter subculture code. Examples include ja-JP for Japanese (Japan) and en-US for English (United States). In cases where a two-letter language code is not available, a three-letter code derived from ISO 639-2 is used.