A "check card", also known as a debit card, will have a visa sign for example. You can use it to pay in the same manner you would pay with a credit card. The money has to be in your account just like a regular checking account. You have a plastic check that doesnt have to be written out. This way you can order off the internet, pay for gas at the pump, make a hotel reservation, or anything in the past that would normally require a credit card. The money has to be in your account just like a regular hand written check. It is for convience.