[en] The discovery of the new heavy particles (the psi family, charmed mesons and baryons) gives new possibilities of a better understanding of the fundamental interactions. The spectroscopy of new hadron families offers a unique opportunity to study quark bound states. They are heavy enough to be understandable in the frame of the non-relativistic quark models. The level spacing and the decay characteristics (selection rules, branching ratios, decay times) are suitable to fit different theoretical models. Due to the large masses of the new hadrons there is in most cases enough energy to produce a lot of light hadrons, therefore the multiparticle models of the strong interaction are applicable. General features of experimental observations, theoretical assumptions and statistical models are discussed in detail. (D.P.)