Question

how does credit card work? can anybody explain this to me in simple words? Thanks...

Answer 1

Can you be more specific?

If you need information on the card itself, look up ISO/IEC 7813. If you've questions about how the cards are used to pay for things, know that it's a complicated system involving at least four parties (merchant, customer, processor, bank) - and the interactions between some of them are proprietary.

At a super high level, a card has two numbers - an issuer number and an account identifier. The issuer number tells the processor what bank controls the account. The account identifier is passed along and tells the bank which actual account the card is associated to. The merchant sends the numbers to the processor with the request, processor makes a decision, pays the merchant, and debits the bank.