  While the pseudogap dominates the phase diagram of hole-doped cuprates,
connecting the antiferromagnetic parent insulator at low doping to the strange
metal at higher doping, its origin and relation to superconductivity remains
unknown. In order to proceed, a complete understanding of how the single hole -
initially localized in the Mott state - becomes mobile and ultimately evolves
into a coherent quasiparticle at the end of the superconducting dome is
required. In order to affect this development, we examine recent transport and
spectroscopic studies of hole-doped cuprates across their phase diagram. In the
process, we highlight a set of empirical correlations between the superfluid
density and certain normal state properties of hole-doped cuprates that offer
fresh insights into the emergence of metallicity within the CuO_2 plane and its
influence on the robustness of the superconducting state. We conclude by
arguing that the overall behavior is best understood in terms of two distinct
current-carrying fluids, only one of which dominates the superconducting
condensate and is gapped out below the pseudogap endpoint at a critical hole
concentration p^\ast.
