ISO Country Code (ISO 3166)
ISO country codes are the unique, short form identifiers for countries. There are two forms - 2-digit and a 3-digit. For example the United Kingdom code is GB (2-digit) and GBR (3-digit). The 2-digit ISO country code is used by many international standards including the International Bank Account Number (IBAN) - ISO 9362 - and the Bank Identifer Code (BIC) - ISO 13616.