Superconductivity theory explains how certain materials can conduct electricity without resistance when cooled below a specific temperature, known as the critical temperature. This phenomenon allows electric current to flow indefinitely without energy loss, making superconductors highly efficient for various applications. The most widely accepted explanation for superconductivity is the BCS theory, named after physicists John Bardeen, Leon Cooper, and Robert Schrieffer. This theory describes how electrons form pairs, called Cooper pairs, which move through the material without scattering, thus eliminating resistance. Superconductivity has potential applications in magnetic levitation, medical imaging, and energy transmission.