This document discusses biometrics technology and its various applications. It describes three main types of authentication: something you know, something you have, and something you are (biometrics). Biometrics refers to using biological and behavioral characteristics to identify individuals. Common physical biometrics include fingerprints, facial features, retina, iris, veins and hand/finger geometry. Behavioral biometrics include keystroke dynamics, voice, gait, and signature. The document outlines several biometric technologies like fingerprint, facial, iris recognition and signature identification. It also discusses applications in security, government, banking, access control and advantages and disadvantages of biometrics.