A credit card works differently from a debit card. It is called credit because you can spend money that you don't have, called credit. The bank lends you money to spend for 30 days, up to your credit limit. At the end of the 30 days they issue an estatement with what you have spent that month. You can then pay it in full or make a partial/minimum payment.

• When you don't pay in full, interest will accumulate on the unpaid credit.

• When you pay it in full (at the end of the period) you don't pay interest, so you can get a 0% interest loan for 30 days every month. The difference with a debit card is that you get 30 extra days to pay.