Authentication plays a vital role in various applications. Even though a number of effective methods and techniques are available, new ideas and techniques are necessary to overcome some of the limitations of these systems. At the present time, biometrics is increasingly gaining popularity in security related applications. Biometrics measure individual’s unique physical or behavioral characteristic to recognize or authenticate their identity and using this technology is far better than any other technology. The word biometrics is very often used as a synonym for the perfect security as proper design and implementation of the biometric system can indeed increase the overall security. There are many biometric technologies to suit different types of applications. This paper discusses the advantages and applications of various biometric technologies.