Like the credit cooperatives, credit unions form associations of a higher level, which are called corporate credit unions. Income received by the credit union shall be distributed among the shareholders or spent for the depreciation of services, that is, are the most effective means of meeting the needs of shareholders. Among the U.S. credit unions, there are three groups that differ in terms of assets, shareholders, and business services. Unlike banks, in order to use the services of a credit union, you have to become its member, having written an application and having paid thus shares and membership fee.