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Over the past six years (2015)(2016)(2017)(2018)(2019)(2020)(2021), many superconducting hydrides with critical temperatures TC up to 250 K, which are currently record highs, have been discovered. Now we can already say that a special field of superconductivity has developed. This is hydride superconductivity at ultrahigh pressures. For the most part, the properties of superhydrides are well described by the Migdal-Eliashberg theory of strong electronphonon interaction, especially when anharmonicity of phonons is taken into account. We investigate the isotope effect, the effect of the magnetic field (up to 60-70 T) on the critical temperature and critical current in the hydride samples, and the dependence of Tc on the pressure and the degree of doping. The divergences between the theory and experiment are of interest, especially in the regions of phase stability and in the behavior of the upper critical magnetic fields at low temperatures. We present a retrospective analysis of data of 2015-2021 and describe promising directions for future research of hydride superconductivity.

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In 2020, the journal Nature published an article under the notorious title ``Room-temperature superconductivity in a carbonaceous sulfur hydride'' (Nature 586 373±377 (2020)) that caused, without exaggeration, an effect like an exploding bomb; after all, it was stated that one of the most important problems in modern physics (implementation of superconductivity at room temperature) has already been solved! In two years, the article has been cited over 500 times and read over 100,000 times. However, in the scientific community, the article led to a great deal of questions, skepticism, and severe criticism. Eventually, on September 26, 2022, Nature retracted this publication. We give here the main reasons for the retraction and our commentary on the significance of this act for the physics of high-temperature superconductivity in general and the superconductivity of hydrides in particular.