Corporate credit unions are united on a cooperative basis in the Central Credit Union (US Central Credit Union). Like any financial institution, credit unions have the financial resources. The uniqueness of credit unions is that they put together the principles and benefits of financial cooperatives, consumer cooperatives and mutual aid funds, born once by trade unions. Cooperation between credit unions, how they would not have been named, took place always, from the moment when the movement moved outside one credit union. Credit unions of the open type are still controlled by their members, but at the same time provide services to people who are not its members (external customers). In the credit union compensation for use of the loan (interest) is a source of compensation for savings. Credit unions are competitors of savings institutions, adding interest on deposits of members. This applies to the shares, as well as to additional funds transferred to the account in the credit union. Historically, credit unions have grown from the experience of credit cooperatives, but they took the experience of organizations of mutual aid of citizens by moving methods of social self-protection from labor and toward consumption.