Technologies which enable people to be identified by their individual physical or behavioural characteristics. These characteristics can be based on an individual's signature, fingerprint, hand geometry, retinal eye pattern, voice or keyboard rhythm for example. Some RFID tags store biometrics, an example being the smart labels being placed in about 400 million passports to conform with new ICAO and other regulations. Some of these have antennas printed directly onto the page and others have chip and printed antenna on a label. Silver ink and screen printing is used at present.