Dear All, I started to look around for a reliable definition of the differences between Calculation, Computation and Simulation, but I'm not satisfied with what I've found. In your view, what are the correct usages of these terms? When something becomes more than a computation or calculation and becomes a simulation? To have a definite question: if I'm solving a differential equation system with a series approximation numerically, what is the correct term for it? Thanks for the answers in advance.