Card networks (or Card schemes)

Payment networks that set rules and provide infrastructure to issue cards and process payments made with cards. For a payment to be made, both an issuer and an acquirer must be members of the same network as the card. Examples of some popular card networks are Visa, Mastercard, American Express, and UnionPay.

Card schemes charge fees for processing payments, and also regulate the value of the interchange fee, which depends on many factors for each specific payment.