In new era, the biometric systems high security applications must match with perfect requirement of real world. This paper gives an overview of multimodal biometrics as well as different fusion of multiple biometrics which helps in minimizing the system error rate & maximizing the recognition rate. The Fusion methods sequentially process biometric modalities until an acceptable match is obtained. This paper also listed the challenges in the progress of multimodal biometrics, the main research areas and its applications to develop the security system for high security areas and enhancing the automation with maximum success rate.