What is a Credit Union?
"A credit union is a friendly, 'not-for-profit,' financial institution that is comprised of members only. Credit unions offer special deals to its members, unlike 'for profit,' big-name banks. Any profit made by the credit union is directed back to members via higher interest rates on savings/checking accounts and lower interest rates on credit cards and loans, unlike a commercial bank, which constantly thinks of new ways to increase its revenue for shareholders via methods such as customer fees."
I couldn't have said it better myself.