When a person applies for a credit card, they are asking a financial institution for a loan that can be used a little at a time as needed. This loan is called a line-of-credit, and the credit card holder is given a plastic card that reflects the loan amount that can be used whenever it is needed.
The financial institution chooses a credit card service to host their credit card transactions. One of the most popular credit card services is the MasterCard brand of credit card. When the financial institution chooses a MasterCard issuer to host their loan services, this issuer provides the financial institution with MasterCard credit card services.
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