This book includes the survey of various pattern recognition techniques with their advantages and disadvantages. In this book authors have nicely explain preprocessing techniques to eliminate the illumination effect from the face images. Different feature extraction and classification techniques are described in the book. This book mainly focuses on the hybrid preprocessing techniques to eliminate the illumination effect from the human face images. The illumination is one of the challenging task which effects the performance of the system. The performance evaluation of hybrid processing techniques was evaluated on the standard human face databases. Authors have created their own human face database and applied different techniques on it.Book focuses various combinations of techniques to achieve higher recognition rate and lower error rate.