The finite element (FE) method is a numerical technique for computing approximate solutions to complex mathematical problems described by differential equations. The method was developed in the 1950s to solve complicated problems in engineering, notably in elasticity and structural mechanics modeling involving elliptic partial differential equations and complicated geometries. But nowadays the range of applications is quite extensive. In particular, the FE method has been successfully applied to many problems such as fluid–structure interaction, thermomechanical, thermochemical, thermo-chemo-mechanical problems, biomechanics, biomedical engineering, piezoelectric, ferroelectric, electromagnetics, and many others. This chapter contains a sum...