Fundamental concepts from quantum information science are playing an increasingly important role in uncovering universal properties of macroscopic quantum systems, a central goal of quantum condensed matter physics. Recently-forged connections between these disciplines are specifically driving an understanding of highly-entangled, equilibrium phases of quantum matter, and revealing universal structures governing quantum many-body systems that have been driven far from their ground-state. I will review some of these important ideas, before showing how tools from quantum information science have led to very recent progress in our understanding of how to foster novel, quantum-coherent phenomena in near-term "quantum simulators", quantum many-body platforms that can be manipulated by an external observer using unitary evolution, measurements, and feedback. Harnessing these elements can produce new mixed-states of macroscopic quantum matter with long-range-order, entanglement, and criticality, which nevertheless coexist with extensive entropy.
