All structures respond to external loads in a nonlinear fashion. However, the nonlinear nature is profound and important in only certain cases. There are several linear and nonlinear solvers that are available to analyze these systems and picking the correct solver is often a choice between computational cost and accuracy. In this Ansys Innovation Course on “Introduction to Nonlinearities” we will present a discussion on what is meant by a structure’s mechanical response and what makes it nonlinear. Upon completion, students will be able to make informed decisions on whether a linear or a nonlinear solver is best suited for analyzing a system.