A contactless smart card is a card in which the chip communicates with the card reader through an induction technology similar to that of an RFID (at data rates of 106 to 848 kbit/s). These cards require only close proximity to an antenna to complete a transaction. They are often used when transactions must be processed quickly or hands-free, such as on mass transit systems, where a smart card can be used without even removing it from a wallet.
The standard for contactless smart card communications is ISO/IEC 14443. It defines two types of contactless cards (“A” and “B”) and allows for communications at distances up to 10 cm.
An alternative standard for contactless smart cards is ISO/IEC 15693, which allows communications at distances up to 50 cm.