RFID (Radio Frequency Identification) is a technology for contactless data transmission on the physical basis of electromagnetic alternating fields, so radio waves. Heart of the RFID technology is an RFID transponder. These small computer chips are provided with tailored to the application antennas and then attached to the objects to be identified. Each RFID tag contains an ID number or number code, such as the Electronic Product Code (EPC, see below). Read is the number code with a reader (see below).