ELI5: Explain Like I'm 5

Conventional superconductor

Conventional superconductors are materials which can carry electrical currents with no resistance, meaning that electricity can flow through them without losing any of its energy. This is because they are made up of atoms which are arranged in such a way that the electrons move freely without bumping into anything that could cause energy to be lost. This makes them really good at not wasting energy when used to power things.