Smart Card: A generic term for a plastic card (usually the size of a credit card) with a microchip embedded in it. Some smart cards contain a microelectronic chip, and smart cards need to interact with data through a reader. The smart card is equipped with a CPU, RAM, and I / O, and can process a large amount of data by itself without disturbing the work of the host CPU. Smart cards can also filter erroneous data to reduce the load on the host CPU. It is suitable for occasions with a large number of ports and fast communication speed requirements. The integrated circuit in the card includes a central processing unit (CPU), a programmable read-only memory (EEPROM), a random access memory (RAM), and a chip operating system (COS) operating in the ROM. The data in the card is divided into external reading and internal processing.