The difference between contactless smart cards & RFID tags

Overview: what happens in RF (radio frequency) communication
When a contactless smart card or an RFID tag passes within range, a reader sends out radio frequency electromagnetic waves.	The antenna, tuned to receive these waves, wakes up the chip in the smart card or tag.	A wireless communications channel is set up between the reader and the smart card or tag.

Source: Gemalto

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