This chapter describes the history of metal rolling, and focuses on the two metals that make up the largest portion of the rolling segment: steel and aluminum. The high-volume, high-speed metal rolling process generates a tremendous amount of heat; and in order to control this heat to an optimum level, it is necessary to provide a cooling function. In the case of metal rolling, the cooling function is the result of the lubricant formulation reducing friction and the resulting heat. According to all rolling theories, the coefficient of friction (COF) existing at the roll bite is directly related to the roll force required for specific thickness reductions. Theory demonstrates that the lower the COF, the lower the rolling force. The initial temperatures of the metal in steel hot rolling are so high that any lubricant would flash off and provide no lubrication value. Cold rolling steel is a more fertile area of opportunity for lubricant design and application.