Currently, secure access constitutes an important topic especially with the lightning computer network development, as well as the size that takes every day Internet in our society. Unfortunately this development generates different problems that sum up to numerous tentative of fraud and even to create new viruses to harm people’s computer.... It became imperative to protect themselves against these tentative, while using means of security available to the public, or while using biometric methods that remain in terms of security the more reliable and most interesting, because these last permit a person's identification on the basis of physiological characters or features automatically recognizable. It is well the reason for which, I chose to speak in my document of the biometric, an existing science for a long time, and that begins to be used more and more in several domains. So we will see the various biometric methods and their workings along this document, as well as the utility of the biometric in the domain of the data processing in general.