 Innovations introduced by economists, traders and merchants of the Muslim world include the earliest uses of credit, cheques, savings accounts, transactional accounts, loaning, trusts, exchange rates, the transfer of credit and debt, and banking institutions for loans and deposits.In Europe, paper money was first introduced in Sweden in 1661.Sweden was rich in copper, thus, because of copper's low value, extraordinarily big coins (often weighing several kilograms) had to be made.