Card payment systems are electronic methods that allow consumers to make purchases using credit or debit cards. These systems process transactions by connecting the cardholder's bank account to the merchant's account, ensuring that funds are transferred securely and efficiently. Common card payment systems include Visa, Mastercard, and American Express. When a customer swipes or taps their card at a point-of-sale terminal, the transaction is authorized through a network that verifies the card's validity and available funds. This process typically takes just a few seconds, making card payments a quick and convenient option for both consumers and businesses.