Lanthanoids and actinoids are f-block transition elements, but their general properties differ significantly from those of d-block transition metals. These elements are place in separate positions in the periodic table showing that the periodicity of their electronic structures differs from the main stream. Although lanthanoids are chemistry utilizing their unique properties is likely to develop significantly in the near future. Actinoids are closely reated to nuclear chemistry and nuclear energy.Since the amount of superheavy elements "synthesized” in acceleratora is very minute,they are not very significant from the viewpoint of applied chemistry.