The operational properties of cars, their meters and indicators, the influence of structural and operational factors on the operational properties, as well as the connection of the latter with the design of the systems and mechanisms of the car are considered. The classification was carried out and the designs of systems, assemblies and mechanisms of various types of cars, their working processes, requirements, advantages and disadvantages were established. On the basis of working processes, calculation elements are set out to determine the loads acting in the units and mechanisms of the car. For higher education students.