According to bankers, the use of credit cards can be divided into "intra-card transactions" and "offline transactions". In the former, the cardholder swipes the card on the POS (sales terminal) of "physical stores" such as shopping malls and supermarkets, and signs the authorization to complete the transaction. Off-line transactions are common in hotels, airline sales centers and corporate finance. Similarly, through the POS system, you can provide the credit card account number and its verification code to complete the transaction.