A card is provided, such as a credit card or security card, that may transmit information to a magnetic stripe reader via a magnetic emulator. The emulator may transmit the information in order to reduce the amount of circuitry needed to emulate a particular block of information. Additionally, for example, one or more buttons may be included on the card. Buttons may be includes, for example, to provide a control interface to navigate through various options of the card. Additionally, coding schemes may be selected via buttons. Furthermore, a card may be locked until a private number is entered into a card or a number may only be generated (e.g., displayed and/or emulated) once a particular private number is entered into a card.