1 introduction2 history of conventional spin wave theory  2.1 theoretical and experimental confusions  2.2 problems with the macroscopic magnetization3 basic issues of renormalization group (rg) theory  3.1 dynamics of non magnetic solids  3.2 dynamics of ordered magnets4 universality  4.1 non-magnetic solids  4.2 ordered magnets5 microscopic processes6 non-relevant magnons7 crossover phenomena  7.1 amplitude crossover (ac)  7.2 quantum state crossover (qs)  7.3 crossover between stable fixed points (sfp)  7.4 symmetry crossover (sc)  7.5 dimensionality crossover (dc)8 metastability of universality classes9 relevant and non-relevant interactions10 temperature dependence of the magnon excitation spectra11 magnetic heat capacity  11.1 nonrelevant magnetic heat capacity for t��o  11.2 relevant magnetic heat capacity for t��o12 experimental verification of gsw bosons13 magnets with and without magnon gap (goldstone mode)  13.1 isotropic magnets with half-integer spin (t2 universality class)  13.2 isotropic magnets with integer spin (t9/2 universality class)  13.3 two-dimensional magnets with half-integer spin (t3/2 universality class)  13.4 two-dimensional magnets with integer spin (t2 universality class)  13.5 one-dimensional magnets with half-integer spin (t5/2 universality class)  13.6 one-dimensional magnets with integer spin (t3 universality class)  13.7 field dependence of the classical magnon spectrum14 microscopic details: spin structure, site disorder, two order parameters15 the critical magnetic behaviour  15.1 isotropic 3d magnets with half-integer spin (t2 universality class)  15.2 anisotropic 3d magnets with half-integer spin (t3/2 universality class)  15.3 isotropic 3d magnets with integer spin (t9/2 universality class)  15.4 anisotropic 3d magnets with integer spin (t2 universality class)  15.5 amorphous ferromagnets  15.6 two-dimensional magnets  15.7 one-dimensional magnets16 thermal lattice expansion and magnetostriction  16.1 spontaneous magnetostriction  16.2 thermal lattice expansion of non-magnetic solids17 the total energy content18 superconductivity  18.1 superconducting heat capacity  18.2 superconducting excitation gap  18.3 problems with landau's order parameter concept19 conclusionsreferencesindex