Credit card processing on websites during checkout typically involves the following steps:

Customer enters payment information: During checkout, the customer is prompted to enter their credit card information, including the card number, expiration date, and security code.

Secure transmission of payment information: The customer's payment information is transmitted securely to the merchant's website using SSL encryption to protect the information from being intercepted or accessed by unauthorized parties.

Payment authorization request: The merchant's website sends an authorization request to the payment processor, including the customer's payment information and the amount of the purchase.

Verification of payment information: The payment processor verifies the customer's payment information, including the credit card number, expiration date, and security code, to ensure that the information is valid.

Communication with acquiring bank: The payment processor communicates with the acquiring bank to determine if the customer's account is valid and has sufficient funds to cover the purchase.

Authorization response: The payment processor sends an authorization response back to the merchant's website indicating whether the transaction is approved or declined.

Payment processing: If the transaction is approved, the payment processor processes the payment, transferring the funds from the customer's account to the merchant's account.

Confirmation and receipt: The customer receives a confirmation of the purchase and a receipt of the transaction.

This process typically takes just a few seconds to complete and helps to ensure that the customer's payment information is protected and that the transaction is processed accurately and securely.