How does a debit card work?

A debit card works by directly withdrawing funds from a consumer's checking account at the time of the transaction. When you use a debit card to make a purchase, the amount is automatically deducted from your available balance. This means that you can only spend what you have in your account, helping to avoid overspending and debt accumulation that can occur with credit cards, which often allow for borrowing against a credit line. The other options presented—borrowing against a credit line, cash back on purchases, and accumulating points for rewards—are features typically associated with credit cards or specific rewards programs, rather than a basic function of debit cards.