What is the difference between a credit card and a debit card?

The fundamental difference between a credit card and a debit is simple: A credit card is tied to a line of credit (LOC) and a debit card is tied to an account that you maintain funds in. What this means is that when you use a credit card, you are borrowing money, and when you use a debit card you are using your own money.

It is possible to get a debit card that is tied to a LOC in the event you overdraft, but that is about as convoluted as the difference can get.