A payment system (hereinafter PS) is a service for transferring money or other funds that replace them (checks, certificates, conventional payment units or specialized securities), in electronic or physical form (hereinafter money). The payment system establishes a certain set of rules, software, hardware and technical means for the transfer of funds from one party to another.

In most cases, not the funds themselves are transferred, but only the debt on them. For example, one client transfers funds within one payment system to another client. In fact, the first client tells the PS that he owes the second client. He, within the time frame established by the PS rules, can contact her to receive money. In reality, their transfer takes place from the first client to the PS, and from the PS to the second client within the time frame agreed by the PS on the basis of the submitted financial presentation.

International payment system (hereinafter MPS) is a payment system whose services are available in different countries.

The most famous payment systems in Europa:

• • National payment card system Mir
  • China UnionPay
  • VISA International Service Association
  • Mastercard
  • JCB
  • American Express
  • Diners Club International