As you read in my article Informed Consent: Ethical Considerations of RFID, radio frequency identification is a network of transponders (tags), readers and software that enables automatic identification and tracking of items from remote locations. Each RFID tag contains an integrated circuit (IC), which is encrypted with a unique electronic product code (EPC) - essentially, an electronic fingerprint. When a tag passes within range of a reader, the EPC is transmitted to the reader through an antenna. The transaction is recorded and retained in the central database, providing real-time track-and-trace of the tagged item.