payment system

mechanism used for making payments

A payment system are the procedures and associated computer networks used to settle financial transactions in bond markets, currency markets, and futures, derivatives and options markets, and to transfer funds between financial institutions. Due to the backing of modern fiat currencies with government bonds, payment systems are a core part of modern currency systems.
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A payment system consists of a set of instruments, banking procedures and, typically, interbank funds transfer systems which facilitate the circulation of money.