Radio-frequency identification (RFID) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders

An RFID system is always made up of two components:
• the transponder, which is located on the object to be identified;
• the interrogator or reader, which is normally a write/read device (the data capture device is always referred to as the reader).

Most RFID tags contain at least two parts. One is an integrated circuit for storing and processing information, modulating and demodulating a (RF) signal. The second is an antenna for receiving and transmitting the signal.

RFID tags come in three general categories passive, active, or semi-passive (also known as battery-assisted).

LAB ID inlays/tags are based on passive RFID technology, which means they require no internal power source.
The minute electrical current induced in the antenna by incoming radio frequency signal provides just enough power for the IC in the tag to power up and transmit a response.