This document discusses payment processing and interchange rates. It provides information on how transactions are processed, the different parties involved, and the various costs associated with processing like interchange rates, monthly service fees, and authorization fees. Interchange rates can vary significantly from 0.00% to 3.10% depending on four factors: the card type, how the transaction was handled, the business type, and the transaction amount. The document emphasizes that the "rate that matters" is the effective rate, which is calculated by taking total fees divided by Visa/Mastercard sales. Examples are provided to illustrate how effective rates can vary from business to business.