A wireless, non contact technology that uses radio waves to transfer data and passively identify a tagged object. RFID systems are usually comprised of an RFID reader, microchip tags, and antennas. The reader gives off radio waves and gets signals back from the tag, while the tag uses radio waves to communicate its identity and other information. The tags are now so small that they can be neatly implanted into paper. They can typically be detected at distances ranging from a few millimetres to several metres. RFID is used in various commercial and industrial applications, including tracking items along a supply chain.