Repayment
With credit you are borrowing money from your credit card balance and are billed monthly, however, with debit you have nothing to pay back since the money is withdrawn from your checking account.
Interest
With each billing cycle, a credit card accumulates interest that must be paid in addition to the original debt. Debit cards, however, charge no interest, since you're not borrowing money.
Credit History
If you use your credit card effectively and responsibly, it can help you build or improve your credit history. But irresponsible usage can damage your credit score. Your everyday debit card transactions don't affect your credit history since you're not borrowing any money.
Fraud
Credit cards may offer you extra protection against unverified charges or fraud, compared to a typical debit card.
Budgeting
Your credit limit allows you to purchase expensive items that you might not be able to afford - and that makes it easy to get into debt. Buying what you don't have money for can become a dangerous financial habit. With a debit card, you're far less likely to overspend since the amount you can spend is equal to the amount in your checking account.