The amount a merchant is charged for its credit card transaction processing involving MasterCard or Visa, this is sometimes called the discount fee and can apply to gross or net sales. The amount charged by the processor is for processing services as well as interchange and assessments paid to the credit card associations or issuing banks.
UniPay Gateway: Open Source Payment Gateway
How to Choose the Best Payment Solution
How to Own a Payment Gateway
What is a Payment Gateway
What is Recurring Billing?
How Payments Work
What Should an Ideal Payment Platform for Investors Look Like?