[Ralath]

For my bank (Bank of America), my savings account gives me a teensy amount of interest and I can only withdraw money 3 times per month without being charged a fee. My checking account doesn't give me interest but it lets me have unlimited withdrawals. I opened both of my accounts at the same time and they're tied together. My credit/debit card is also tied to my checking account. My card (and most cards now) will let you run your bank card as both credit and debit and they work the same way.

If your credit card isn't tied to a bank account, then you have to remember to pay it off at the end of the pay cycle.