Generally speaking, modelling is a tool that enables a controlled analysis of problems by mapping a physical/technical problem to an appropriate equivalent form. In case of mathematical mappings, it is often difficult or even impossible to solve such models explicitly. The only tool available to the analyst is numerical modelling, a priori taking the approach of approximative solving and moving the treatment from the continuous to a discrete space. The student learns the principles and masters the methods of physically objective numerical modelling. Based on simple technical cases, the student learns to understand mathematical models, recognize the significance of physical quantities appearing in the model, as well as their role in defining the boundary value problem. The approximation approach to solving boundary value problem equations has a general setting with differential and integral formulations used as the starting points. The Finite difference method and the Finite element method are their direct numerical derivatives.