Credit card verification code is actually a security code, which is a verification code used for identity verification. Usually the last three digits printed on the signature on the back of a credit card are used to prove that the payer has a credit card at the time of transaction, thus preventing credit card fraud. The check code is equivalent to the ID card of a credit card, and the cardholder can use this code for consumer transactions. Its importance is almost equal to password.
Its generation method is that the bank extracts the account number, validity period and service code of the card, arranges them and then calculates them through a series of complicated algorithms. After this set of numbers is generated, only the issuing bank and the holder of the bank card know what this number is.
The Cvv code is the last 3 digits printed on the signature column on the back of the credit card.
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Credit Card Knowledge of China Construction Bank
1, annual fee-free policy: the annual fee for the following year is free if you swipe your card for 3 times or 18 times (excluding special cards such as business cards and car cards).
2. Withdrawal fee: domestic: 5‰ of the transaction amount, with the lowest 2 yuan and the highest 50 yuan; Overseas: 3% of the transaction amount, with a minimum of $3.
3. Multi-account management: quota sharing, multiple CCB cards with the same billing date and independent repayment.
4. Online payment: Alipay: it can be used after online registration, with a single payment and a one-day limit of 500 yuan.
5. Staging business: support interest-free staging for specific merchants (3, 6, 12). After a single consumption exceeds 1000 yuan, you can apply for installment by phone (3, 6, 12, 18, 24), and different handling fees will be generated according to the number of installments.
6. Billing date: There are multiple billing dates every month, and the cardholder can change it once a year within the validity period of the card.
Baidu encyclopedia-credit card security code
Baidu Encyclopedia-CCB Credit Card