In today's networked world, the need to maintain the security of information or physical property is becoming both increasingly important and increasingly difficult. From time to time we hear about the crimes of credit card fraud, computer break-in by hackers, or security breaches in a company or government building. This book provides an inclusively study of face detection and recognition techniques. It demonstrate each method algorithm, how does it works to perform its job, and explain in details what is the process of each step along the algorithms to reach the desired goal. This document contains a code for each method this code in tested and certainly works.