The laws and findings of tribology as an applied science are also applicable to the entire field of mechanics, from the bearing arrangement of a brown coal excavator with a diameter of 1 m to the bearing in a miniature gear with a diameter of only 0.1 mm. According to one definition, precision mechanics begins with bearing diameters of less than 5 mm (Figure 21.1), but this definition is purely arbitrary. The difference between the classical mechanics of mechanical engineering and precision mechanics consists only of the dimensions of the components. However, downscaling creates typical problems and particulars. This is also true in the automobile.