Electronic payment systems allow for financial transactions between buyers and sellers online through digital payment methods like credit cards, debit cards, and digital cash. They provide benefits like convenience, choice of payment options, improved cash flow, and competitive advantages for businesses. However, they also carry risks like stolen credentials, fraudulent transactions, disputes over purchases, and insufficient funds in accounts. The key electronic payment methods discussed are credit cards, debit cards, smart cards, e-money, electronic funds transfer, and electronic checks.