The payment system is an operational network - governed by laws, rules and standards - that links bank accounts and provides the functionality for monetary exchange using bank deposits. The payment system is the infrastructure (consisting of institutions, instruments, rules, procedures, standards,and technical means) established in effect the transfer of monetary value between parties discharging mutual obligations. Its technical efficiency determines the efficiency with which transaction money is used in the economy, and risk associated with its use.
What makes it a "system" is that it employs cash-substitutes; traditional payment systems are negotiable instruments such as drafts (e.g., checks) and documentary credits such as letter of credits. With the advent of computers and electronic communications a large number of alternative electronic payment systems have emerged. These include debit cards, credit cards, electronic funds transfers, direct credits, direct debits, internet banking and e-commerce payment systems. Some payment systems include credit mechanisms, but that is essentially a different aspect of payment. Payment systems are used in lieu of tendering cash in domestic and international transactions and consist of a major service provided by banks and other financial institutions.
Payment systems may be physical or electronic and each has their own procedures and protocols. Standardisation have allowed some of these systems and networks to grow to a global scale, but there are still many country and product specific systems. Examples of payment systems that have become globally available are credit card and automated teller machine networks. Specific forms of payment systems are also used to settle financial transactions for products in the equity markets, bond markets, currency markets, futures markets, derivatives markets, options markets and for transfer funds between financial institutions both domestically using clearing and Real Time Gross Settlement (RTGS) systems and internationally using the SWIFT network.
National payment system 
An efficient national payment system reduced the cost of exchanging goods and services, and indispensable to the functioning of the interbank, money, and capital markets. A weak payment system may severely drag on the stability and developmental capacity of a national economy; its failures can result in inefficient use of financial resources, inequitable risk-sharing among agents, actual losses for participants, and loss of confidence in the financial system and in the very use of money  The technical effciency of payment system is important for a development of economy. Real time gross settlement systems (RTGS) are funds transfer systems where transfer of money or securities takes place from one bank to another on a "real time" and on "gross" basis. Settlement in "real time" means that payment transaction does not require any waiting period. The transactions are settled as soon as they are processed. "Gross settlement" means the transaction is settled on one to one basis without bunching or netting with any other transaction. Once processed, payments are final and irrevocable.
RTGS systems covering multiple countries: TARGET resp. TARGET2 (Trans-European Automated Real-time Gross Settlement Express Transfer System) in 26 countries of the European Union. TARGET2 is the Real Time Gross Settlement system for the Euro currency, and is offered by the Eurosystem, which comprises the European Central Bank and the National Central Banks of those countries that have adopted the Euro currency. The Eurosystem and the European System of Central Banks will co-exist as long as there are EU Member States outside the Euro area. TARGET2 is used for the settlement of central bank operations, large-value Euro interbank transfers as well as other euro payments. TARGET 2 provides real-time financial transfers, debt settlement at central banks which is immediate and irreversible.
This "electronic" payment system is normally maintained or controlled by the Central Bank of a country. There is no physical exchange of money; the Central Bank makes adjustments in the electronic accounts of Bank A and Bank B, reducing the amount in Bank A's account by $100,000 and increasing the amount of Bank B's account by the same. The RTGS system is suited for low-volume, high-value transactions. It lowers settlement risk, besides giving an accurate picture of an institution's account at any point of time. Such systems are an alternative to systems of settling transactions at the end of the day, also known as the net settlement system such as BACS. In the net settlement system, all the inter-institution transactions during the day are accumulated. At the end of the day, the accounts of the institutions are adjusted. The implementation of RTGS systems by Central Banks throughout the world is driven by the goal to minimize risk in high-value electronic payment settlement systems. In an RTGS system, transactions are settled across accounts held at a Central Bank on a continuous gross basis. Settlement is immediate, final and irrevocable. Credit risks due to settlement lags are eliminated. The best RTGS national payment system cover up to 95% of high-value transactions within national monetary market. The World Bank has bee paying increasing attention to payment system development as a key component of the financial infrastructure of a country, and has provided various form of assistance to over 100 counrites. Most of the RTGS systems in place are secure and have been designed around international standards and best practices. By 1985 only 3 central banks had implemented RTGS system. At the end of 2005, the use of RTGS systems had diffused to 90 central banks.
- "Payment Systems: Design, Governanca and Oversight", edited by Bruce J. Summers,Ctntral Banking Publications Ltd, London, 2012, p.3
- Biago Bossone and Massimo Cirasino, "The Oversight of the Payment Systems: A Framework for the Development and Governanace of Payment Systems in Emerging Economies"The World Bank, July 2001, p.7
- Biagio Bossone and Massimo Cirasino, Op.Cit, p.7
- Massimo Cirasino and Jose Antonio Garcia, " Measuring Payment System Development", The World Bank, 2008
- Morten Bech, Bart Hobijn, " Technology Diffusion within Central Banking: The Case of Real-Time Gross Settlement", Staff Report nj. 260, Federal Reserve Bank of New York, Working Paper, September 2006, p.2
See also 
- Clearing house
- Credit card
- Debit card
- Direct Deposit
- E-commerce credit card payment system
- E-commerce payment system
- Electronic bill payment
- Electronic commerce
- Electronic funds transfer
- Interbank Network (ATM / EFT / EFTPOS )
- List of on-line payment service providers
- Online banking
- Payment card
- Payment service provider
- Payments as a Service
- Real Time Gross Settlement
- Society for Worldwide Interbank Financial Telecommunication
- Systemically Important Payment Systems
- Wire transfer