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. Credit union is created by a group of members who pursue a common interest. Agreeing to make regular contributions, they create a fund from which can borrow money for investments and replenishment of working capital at favorable interest rates. Until the 70's there was a proliferation of the U.S. credit unions due to the increase of their number and the number of shareholders, although it must be acknowledged that there was also and a qualitative growth. 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.