Biomechanics is the study of the structure and function of biological systems such as humans, animals, plants, organs, fungi, and cells by the method of mechanics. Biomechanics is closely related to engineering, because it frequently uses traditional engineering sciences to analyze biological systems. Some simple applications of Newtonian mechanics and materials sciences can supply correct approximations to the mechanics of many biological systems. Applied mechanics, mostly mechanical engineering disciplines such as continuum mechanics, structural analysis, kinematics, mechanism analysis, and   dynamics play prominent roles in the study of biomechanics.Usually biological systems are more complicated than man-built systems. Numerical methods are hence implemented in almost every biomechanical study. Research is done in an iterative process of hypothesis and verification, including several steps of modelling, computer simulation and experimental measurements.