To throw in a bit of confusion, most US debit cards can also be run on credit card networks (mostly Visa or Mastercard, though when I worked as a cashier I saw

To throw in a bit of confusion, most US debit cards can also be run on credit card networks (mostly Visa or Mastercard, though when I worked as a cashier I saw a few debit cards that used Discover or Amex). The cash is still directly debited from your bank account, but that lets you use the card at places that do accept credit cards but don't belong to any of the dozen different debit networks (STAR, Pulse, CO-OP, etc.). This is also why most US-based online shops prefer credit cards since it's assumed that even if you don't have an actual credit card you have a debit card that can be run as one.