In volume III/21 the data on superconducting materials, from the discovery of this phenomenon to the present days of intensive research on high-Tc superconductors, are compiled. The data comprise various modifications of a material, e.g. bulk state, thin films, implanted or filamentary wires. Where available, data obtained under high pressure or after high energy particle irradiation are also tabulated. A particular effort was made to present the complete characterization of the analyzed samples, i.e. the metallurgical and the crystallographical analysis as well as the analysis of other physical properties. The goal of the volume is to establish a complete and reliable compilation of critically reviewed experimental data from more than 40.000 publications, excluding purely theoretical works.