Nuclei in their ground states behave as quantum fluids, Fermi liquids. When the density, or the temperature of that fluid increases, various phase transitions may occur. Thus, for moderate excitation energies, of the order of a few MeV per nucleon, nuclear matter behaves as an ordinary fluid with gaseous and liquid phases, and a coexistence region below a critical temperature. For higher excitation energies, of the order of a few Ge V per nucleon,...