Answer:
Superconductivity is a phenomenon that occurs when a substance (typically metallic or ceramic) reaches its "critical temperature" (Tc) and loses all electrical resistance. This occurrence takes place at extremely low temperatures, which renders much of the scientific potential difficult to apply to real life situations.
Scientists are currently working on developing superconductors that are closer to room temperature, an improvement which would make superconductors much more important to everybody. Superconductors have the potential to carry an electric charge across an infinite distance without losing any energy whatsoever, and also block out magnetic fields because of the Meissner Effect. If controlled in room temperature, it would be possible to transport electricity from a power plant on Earth to a residential area on Mars, create lightning-fast computer circuits with no resistance, develop weapons such as quickly-reloadable rail guns, and transportation possibilities such as biohazard-free levitating trains.