1, payment and settlement; The payment and settlement function of credit card can provide a wide range of settlement services, facilitate cardholders' shopping and consumption activities, reduce the use of cash and money in society, speed up the circulation of money and save social labor. 2. Exchange transfer; The remittance function of credit card is embodied in the process of cardholder's going out for business trip, sales and vacation. In different places or even abroad, funds can be transferred by remittance through the outlets of member institutions of any international credit card organization. 3. Scale purchase; As the representatives of all members-all cardholders, card issuers should gain more bargaining power from sellers through correct market forces, so that cardholders can share more negotiation benefits. For example, American Express, Citibank and other institutions generally provide cardholders with additional services such as discounts on credit card consumption and ensuring the lowest price for credit card shopping. 4. Personal credit; Cardholders can accumulate personal credit in financial institutions by using credit cards, and the accumulation of long-term excellent credit will bring many high-value returns to cardholders. Personal credit will involve all aspects of the cardholder's daily economic life. 5. selling on credit; Credit card is essentially a credit purchase and sale certificate, and its operation mode reflects the support of commercial credit or bank credit. In fact, today's credit purchase and sale function of credit cards has changed from the initial commercial credit behavior to the bank credit behavior. The credit purchase and sale of credit cards has changed the traditional mode of consumption payment, expanded the scale of social credit, changed the direct transaction mode of cash on delivery into circuitous transaction, and changed the situation that the actual purchasing power of social money determines the social purchase behavior. Advanced purchasing power and expanded credit scale will inevitably expand the total social demand. In order to ensure the overall balance of the macro-economy, it is necessary to increase the total social supply to adapt to the expanding total social demand, thus promoting social and economic development. 6. Revolving credit; Credit card is essentially a kind of consumer credit, which provides a revolving credit account with a clear credit limit. The borrower can use part or all of the credit line, and once the used balance is repaid, the credit line can be restored. Especially for credit card holders, as long as a certain minimum repayment amount is paid every month, the account and loan interest beyond this amount can be postponed to the next repayment period. If the borrower's account has been under the condition of revolving credit, the balance of the circulating loan can almost be regarded as an indefinite loan. Through revolving credit, cardholders can accumulate their own credit in financial institutions. 7. Other functions. Although the basic functions of credit cards are basically the same, credit card products with different types, functions and services can be formed through the differentiated services provided by card issuers, with different emphasis on different target customer groups. Therefore, there are countless functions. The differentiated functions and value-added services of credit cards are largely limited by the actual needs of society and the business expansion and product development capabilities of card issuers. (2) Use of credit card 1. Cardholders who purchase credit cards can settle accounts with cards in hotels, restaurants, restaurants, shops and other commercial institutions or outlets that accept credit cards. Shopping consumption is the most basic and primitive way to use credit cards. After checking in, dining and shopping, the cardholder does not need to pay any fees immediately, just show his credit card. The cashier can use the stamp machine or POS machine to handle the transaction, and the cardholder's account can be 2. Withdrawal is an auxiliary use of credit cards. Cardholders can withdraw savings deposits from credit card accounts or borrow cash in advance at the branch counters or ATMs of card issuers. In fact, in foreign countries, card issuers do not encourage cardholders to use credit cards to withdraw cash, especially credit cards. Because the first credit card, debit card, is essentially characterized by credit sales and revolving credit, not just for the convenience of payment and settlement. 3. Payment of expenses. Savings For some types of credit cards, such as quasi-debit cards and debit cards, the card issuer pays interest on the balance in such accounts, so it can be used for saving deposits and withdrawals, even more convenient than current time deposits, and it is not limited by the coverage of the card issuer's outlets. With the help of ATM, inter-bank and inter-regional deposit and withdrawal can be realized. 5. The inherent core characteristics of installment credit card determine that it can realize installment shopping through revolving credit. In fact, the revolving credit provided by the credit card is a small consumer loan provided by the card issuer to the cardholder, which allows the cardholder to purchase credit with the credit card and realize installment shopping through partial repayment. 6. Microfinance credit card not only has the function of fund payment, but also can be used by cardholders to make microfinance, thus benefiting both parties to the transaction. Consumers get convenient loans, so as to better realize the synchronization of income and expenditure; Franchise merchants can sell goods to customers who can't pay cash, and speed up capital turnover through credit sales, thus expanding the scale of operation. Merchants can not only get all the benefits brought by credit sales, but also avoid the costs and risks of providing commercial credit to consumers. In addition, credit cards are especially favored by small businesses or self-employed individuals who lack funds. In fact, financing difficulties for SMEs are very common. Many entrepreneurs in small businesses have to use personal credit cards to overdraw their loans. When other credit means are not feasible, they can only resort to credit card overdraft. Of course, this general situation also shows that many entrepreneurs can use personal credit overdraft to support their own enterprises, which provides an excellent incremental capital support for many small companies in the initial stage. 7. Credit certificate Since credit cards are generally issued by card issuers according to the applicant's social status, economic strength, purchasing power and credit rating, cards are generally classified according to the credit rating of the cardholder. In addition, the credit card also has the function of credit purchase, so the credit card can be used as a symbol of identity and a reflection of the cardholder's credit rating on many occasions. For example, credit cards with platinum cards and gold cards usually have many high-level value-added services, including VIP services, VIP treatment at global airports, discounts for special merchants and so on.