A credit card number is a unique series of digits assigned to a specific credit card that allows you to make purchases. This number typically consists of 16 digits, which are divided into groups. The first few digits identify the card issuer, while the remaining digits represent your individual account. When you use your credit card for shopping, the number is processed to verify that you have enough funds to complete the transaction. It's important to keep your credit card number safe, as sharing it can lead to fraud or unauthorized charges on your account.