In engineering, a system is understood to be a set of physical elements acting together and realizing
a common goal. An important role in the analysis of the system is played by its mathematical
model. It is created using the system structure and fundamental physical laws governing the system
elements. In the case of complicated systems, mathematical models usually do not have a universal
character but rather reflect some characteristic phenomena which are of interest. Because of mathematical complications, practically used system models are usually a compromise between a required accuracy of modelling and a degree of complication.