Can I use a debit card to pay for something online,in place of a credit card?

Do I have too use a credit card or can I just use a debit card where is says credit card number?I have a mastercard debit card.|||Yes you can.|||Yes you can but you may not want to. Debit cards come directly from your checking account and fraud can cost you dearly if you can't even buy groceries until it's straighten out. If it happens with your credit card it it much easier to resolve and it doesn't affect your cash flow.|||Yes, I do it a lot. That is why we are asked at the store credit or debit so it can be used either way.|||Yes, I do it all the time.