Eclipsing variables are the richest source of information about the physical properties of stars. Periodically repeated eclipses cause a relatively short-term weakening of the total brightness of the binary system. Modern accurate methods of photometric observations make it possible to establish the functional dependence of the change in the brightness of the system on time - to build a fairly reliable curve of the change in brightness. Mathematical study of the light curve allows you to determine not only the elements of the binary system...