Contact smart cards are the size of a conventional credit or debit card with a single embedded integrated circuit chip that contains just memory or memory plus a microprocessor.
Memory-only chips are functionally similar to a small floppy disk. They are less expensive than microprocessor chips, but they also offer less security so they should not be used to store sensitive or valuable information.
Chips that contain both memory and a microprocessor are also similar to a small floppy disk, except they contain an "intelligent" controller used to securely add, delete, change, and update information contained in memory. The more sophisticated microprocessor chips have state-of-the-art security features built in to protect the contents of memory from unauthorized access.
Contact smart cards must be inserted into a card acceptor device where pins attached to the reader make "contact" with pads on the surface of the card to read and store information in the chip. This type of e-card is used in a wide variety of applications including network security, vending, meal plans, loyalty, electronic cash, government IDs, campus IDs, e-commerce, health cards, and many more.