Abstract. Superconductivity is discussed as an astonishing property of the materials that involve many different types of applications. On fundamental level it represents a direct, macroscopic manifestation of coherent quantum mechanical behavior. The discovery of high temperature superconductors (1986) and new Iron based materials (2008) is noticed. A short introduction to the properties of the last family is given, comparing them with well established facts for cuprate perovskites. Discussion is provided about the crystal and band structure, interplay between magnetism and superconductivity, possible pairing mechanisms, anisotropy, basic critical parameters — critical temperature, critical magnetic field and critical current. Special attention is paid to superconductor-insulator quantum transition, important for non-conventional superconductors. Its deep understanding is essential for solving the problem of Cooper pairing and will help for creation of new superconducting materials. A brief presentation of the first results on synthesis of iron based superconductors at the Institute of Solid State Physics is presented.

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