  On the occasion of centenary of superconductivity discovery I recall some
facts from the first period and attempts to understand the phenomenon. It turns
out that most famous physicists of the first half of XX century have tried to
solve the puzzle. Bardeen, Cooper and Schrieffer succeeded in 1957. The BCS
theory successfully described all known facts and offered new predictions,
which soon have been confirmed experimentally contributing to the widespread
acceptance of the theory. It have found applications in nuclear physics, theory
of neutron stars and cold atomic gases. The discoveries of new superconductors
in the last thirty years show that simple BCS model is not enough to understand
new unconventional superconductors. The studies of superconductors develop
vividly and still fascinate new generations of physicists working in such
diverse fields as material science and string theory.
