NFC Card Emulation Mode
Card Emulation is an NFC mode in which an NFC device acts like a passive NFC tag such that the NFC tag can be interacted with by a different NFC device in reader/writer mode. “Tag” emulation would be a better name as the NFC device is emulating a NFC tag, but NFC has its roots in the Smart Card space. Not all NFC controllers support card emulation; check the technical specifications of the NFC device for what NFC modes are supported. Card emulation is a specialized mode, only used in transportation, loyalty and payments; it is not frequently used in Connected Things projects.