The RFID tag is an electronic tag that exchanges data with an RFID reader through radio waves. The two types of RFID tags are active RFID tags which have a transmitter and their own power source (typically a battery) and the others are passive RFID tags in which the coiled antenna within the tag forms a magnetic field which draws power from it, energizing the circuits in the tag and then sends the information encoded in the tag's memory: http://bit.ly/RFID-Tags














