RFID is the used of a wireless non-contact system that uses radio-frequency electromagnetic fields to transfer data from a tag attached to an object, for the purposes of automatic identifications and tracking. Some RFID tags require no battery and are powered by the electromagnetic fields used to read them. Others use a local power source and emit radio waves.

RIFD tags contains electronically stored information which can be read from up to several meters (yards) away. Unlike a barcode label, RFID tag does not need to be within line of sight of the reader and may be embedded in the tracked object.