Progress in experimental research of physics of superconductivity

After a brief review of the superconductivity research before 1986, recent experimental progress in the research of the high-Tc cuprates is overviewed. High-Tc superconductivity has changed landscape of physics of superconductivity as well as condensed matter physics by stimulating a rapid development of advanced spectroscopies. They continue to reveal unusual properties of both normal and superconducting states, such as coexistence of competing orders and strong quantum fluctuations. However, new mysteries of high-Tc superconductivity emerge from these experimental findings. (author)