Surface Energy is defined as the sum of all intermolecular forces that are on the surface of a material, the degree of attraction or repulsion force of a material surface exerts on another material. This can be looked at as the repulsion or attraction of two magnets. Low energy surfaces are slippery and high energy surfaces are not. For example, when water is applied to a newly waxed car the water beads up. The surface of the wax has a low energy so the water rolls of the surface. However, when water is applied to the car before waxing the water spreads out and flows off of the surface. The water has a better affinity to the unwaxed surface.