This card is the only way you will be able to spend money while on the ship. It is also the only way you can get off and on the ship as well and get into your room. You will have to put up a deposit for the money you plan to spend while onboard if you aren't using a credit card. The ship will issue you a sign and sail card to use for all your purchases while onboard. Each day on the television in your room you can check your balance by entering your pin number into the TV. The number will be on your card. DON'T misplace it because someone else could use it to buy things. When you leave the ship at port you will scan this card before getting off. The ship will know that you are at port. When you come back, same thing, you check back in. If you don't check back in, they will know you are missing from the ship via computer.