The document discusses cooling curves and phase diagrams. It explains that a cooling curve graphs the solidification of molten metal over time and temperature, and can show pure metals, binary solutions, and binary eutectic systems. Phase diagrams show the phases present at different compositions and temperatures under equilibrium conditions. They include diagrams for complete and partial solid solubility, as well as those containing eutectic, peritectic, eutectoid, and peritectoid reactions. Interpreting phase diagrams allows determining phase composition and amount at any given conditions.