Abstract: Biometric is newest technology in the security field. It uses the inherent characteristic to authenticate persons. This in turn will enhance the reliability of the security systems compared to the traditional based authentication systems such as password or code and solve many of the problems that appeared in the traditional based systems. This leads to using biometrics systems widely in many applications . Many features in the human's body can be used as biometrics if they meet specific requirements .Each one of these biometrics have strength and weakness points. This paper will discuss the commonly used biometrics.

Keywords: Biometrics,Authentication,Verification,Identificatin,Feature Extraction.