A superconductor is an occurrence of exactly 0 internal resistance to electrical charges and the removal of interior magnetic fields, known as the Meissner Effect. During this change, all magnetic flux within the material is transferred to the outside, greatly multiplying the outside field. Super conductance was discovered in 1911 by Dutch physicist Heike Kamerlingh Onnes. And, it’s actually a phenomenon of quantum mechanics.
Superconductors are made when a material is cooled to below that material’s critical temperature. And, they can break down once the magnetic field around them grows too great as well. There are currently two classes of superconductor based on how they break down. Type I superconductors abruptly stop conducting in this way if the field breaches a certain threshold value. Type II superconductors begin to accept magnetic flux back into the material above the threshold point, but retain their 0 resistivity. It is because of these quirky effects that superconductors cannot simply be seen as perfect, or ideal, conductors, but rather entirely separate phenomena.
Scientists still study superconductors and their applications in depth today. In 1986 ceramic materials were shown to have very high critical temperatures, ones that were theoretically impossible, and were dubbed high-temperature superconductors.
Nowadays superconductors are used in particle accelerators and mass spectrometers due to their incredible power as electromagnets. However, they have all kinds of fascinating circuitry and quantum mechanics applications. Feel free to investigate yourself, but for now, enjoy a video of a superconductor floating above a magnet, known as quantum levitation.