Fluid dynamics has a long tradition. It is a discipline which concerns a lot of occurrences which we daily encounter. Liquid flows as well as gas flows escort us in our domestic home, come along with moving cars, trains, airplanes and ships and their propulsion systems, are the dominating effect of the formation of weather events, determine often the processes of chemical engineering systems and are the main drivers in numerous power plants, just to mention some of their scopes of influence. With the development of the appropriate mathematical skills, which started somewhere along the seventeenth century, equation systems for more or less all possible flow fields were established. Today, with the numerical integration methods we have means available to solve rigorously all these equation systems.