Superconductivity--the flow of electric current without resistance in certain materials as temperatures near absolute zero--is one of the greatest discoveries of 20th century physics, but it can seem impenetrable to those who lack a solid scientific background. Outlining the fascinating history of how superconductivity was discovered, and the race to understand its many mysterious and counter-intuitive phenomena, Stephen Blundell explains in accessible terms the theories that have been developed to explain it, and how they have influenced other areas of science