The document discusses electronic payment systems and their security. It describes various electronic payment methods like e-cash, smart cards, credit cards, and e-wallets. E-cash works like digital cash that is issued by banks and can be spent anonymously. Smart cards contain embedded chips that can process payments. Credit cards allow purchases with repayment later while e-wallets store payment details and act as digital wallets. Payment gateways provide secure transaction processing between customers, merchants and payment processors. Electronic payment systems enhance convenience and expand markets beyond geographical boundaries.