This paper deals with biometric security and addresses the beginnings of biometrics, biometric system functions, biometric methods used for identification and authentication and the working principe of specified methods. Furthermore, the paper deals with areas where biometric security is implemented, but also the importance of these in different spheres of life. This research is carried out by dealing with the published literature so far and is seeking the overall importance of this topic. Biometric security and knowledge of this area is needed because today most people are considered biometric security users and are using biometric systems as a way to protect almost all of their information. Finally, the reader will receive desirable knowledge of this area, ie. information on what methods of biometric security contribute to the preservation of data, but also which are the most accurate and most effective methods and the principle of work.