Contactless credit cards, that is "contactless", are payment cards that make it easier and faster to carry out transactions than traditional cards.
Unlike common microchip and magnetic strip cards, which must be physically inserted into a terminal (POS) to complete the payment, contacless cards allow the user to settle their accounts simply by bringing them closer to a reader, therefore without contact.
These cards, apparently completely identical to the normal ones, contain within them a radiofrequency circuit called RFID which allows data transmission without physical contact.
The reader emits a radio signal at frequencies of some GigaHertz which "excites" the RFID circuit and provides it with the necessary energy to transmit the information it has stored inside it, ie the card number, expiration date and other data necessary for the conclusion of the transaction.
At a theoretical level these cards, simplifying and speeding up the payment process also with respect to cash, should facilitate the spread of electronic money especially for small and very small purchases. Currently, the spread of contactless cards is still rather limited, although some banks and large-scale retail chains have already started with the first large-scale trials.