-Bio met ric systems are alternates to the traditional identification systems. This paper p rovides an overview of single feature and mult iple features based biometric systems, including the performance of physiological characteristics (such as fingerprint, hand geometry, head recognition, iris, retina, face recognition, DNA recognition, palm prints, heartbeat, finger veins, palates etc) and behavioral characteristics (such as body language, facial exp ression, signature verification, speech recognition, Gait Signature etc.).The fingerprints, iris image, and DNA features based mu ltimodal systems and their perfo rmances are analyzed in terms of security, reliab ility, accuracy, and long-term stability. The strengths and weaknesses of various mult iple features based biometric approaches published so far are analyzed. The d irect ions of future research work for robust personal identification is outlined.