A gift card may resemble a credit card or display a specific theme on a plastic card the size of a credit card. The card is identified by a specific number or code, not usually with an individual name, and thus could be used by anybody. They are backed by an on-line electronic system for authorization. Some gift cards can be reloaded by payment and can be used thus multiple times.
Cards may have a barcode or magnetic strip, which is read by an electronic credit card machine. Many cards have no value until they are sold, at which time the cashier enters the amount which the customer wishes to put on the card. This amount is rarely stored on the card but is instead noted in the store's database, which is crosslinked to the card ID. Gift cards thus are generally not stored-value cards as used in many public transport systems or library photocopiers, where a simplified system (with no network) stores the value only on the card itself. To thwart counterfeiting, the data is encrypted. The magnetic strip is also often placed differently than on credit cards, so they cannot be read or written with standard equipment. Other gift cards may have a set value and need to be activated by calling a specific number.
Gift cards can also be custom tailored to meet specific needs. By adding a custom message or name on the front of the card, it can make for an individualized gift or incentive to an employee to show how greatly they are appreciated.