These cards combine two interfaces, including contact and contactless. The same chip can be accessed by either method with these cards, making them extremely secure. These cards also contain two different types of chips: microcontroller chips and memory chips. The memory chip functions as a small floppy disk, but with added security. Microcontrollers are significantly cheaper than memory chips, but they do not offer as much data security as memory chips. Information in the microcontroller chip can be added, removed, or otherwise modified. The microcontroller has input/output ports, an operating system, and a hard drive. A microcontroller embedded in a smart card is capable of storing large amounts of data, performing on-card functions (e.g., encryption and digital signatures), and communicating intelligently with a smart card reader.