The Currency represents the currency in reality. CurrencyUnit is measurement unit of a Currency. Currency uses 1 or more CurrencyUnits. For example, Currency (code=CNY, symbol= ￥) uses three CurrencyUnits (Yuan, Jiao, Fen). Each CurrencyUnit might have a specific name according to the Language (CurrencyUnitName). For CurrencyUnitName Yuan associated to Language (alphabetName=Chinese), CurrencyUnit (rate =1, isStadUnit = True, isMinUnit = False). Under different languages, a CurrencyUnit has different names, e.g Yuan in English and 元 in Chinese to express the same basic currency unit in Chinese currency. A Currency might be exchanged with a specific rate. So Currency is associated to many CurrencyExchangeRates with CurrencyUsedAsSource and CurrencyUsedAsDestination relationships. Currency can be used in many different Countries and for each language a specific name might exist (CurrencyName) such as Renminbi Yuan in English and 人民币元 in Chinese to express the same Chinese currency. PartyRoleCurrency represents the currency that PartyRole may use. AccountCurrency represents the currency that might be used for producing bills related to the Account. One of them specifies the default Currency used.
