The principle problems of the new developing scientific field - dynamics of vehicles, tracks and roads - are defined. Basic theoretical models for the analysis of railway and road vehicles, tracks and roads and principle methods fo their solution are shown. The dynamic interactions between vehicles and routes are emphasized and several basic equations are given to show the behavior of their elements. The effect of some parameters, like speed, track or roads irregularities etc. is explained. The possibilities are described how to simplify the theoretical models to obtain a simple solution.