One hundred years after its discovery in Leiden, superconductivity, the remarkable ability of some metals to carry current without resistance and shield out external magnetic fields, continues to be a poster child for emergent behavior in quantum matter. It is a leading research topic in the condensed matter and materials communities, with many applications realized, and the promise of many more to come. While the mechanism for superconductivity in the so-called conventional superconductors was explained by Bardeen, Cooper, and Schrieffer over 50 years ago as a net attractive interaction between electrons induced by their coupling to lattice excitations that gives rise to a macroscopically occupied single quantum state, a condensate formed by pairs of electrons, no consensus has yet been reached on the physical origin of that attraction in the more recently discovered unconventional superconductors--the heavy electron, organic, and high superconducting transition temperature cuprate and iron materials. These last two families, together with materials yet to be discovered, offer the vision of magnetically levitated trains and transmission lines with no power loss, while the proposal that stars made up primarily of neutrons would contain celestial superfluids has been realized with the discovery of pulsars for which glitches reveal the presence within them of superfluid neutron matter with transition temperatures approaching 1 million degrees Kelvin.