This training package fully covers the various possible methods for welding simulation. First, an introduction to welding and two basic categories of welding, fusion and non-fusion welding. Next, the theories and the elements used to simulate the welding will be explained. These theories are Lagrangian, Eulerian, ALE, and SPH. After that, you will learn how to apply these theories with different methods, such as the death and birth of an element, DFLUX subroutine, etc. Finally, you will learn how to simulate welding with the help of five workshops: Friction Stir Welding (FSW) simulation with the Eulerian element, Explosive welding simulation, simulation of FSW with the SPH method, Butt welding with death and birth of an element method, and Simulation of Arc welding between two tubes with DFLUX subroutine (Thermomechanical Analysis).