The shape of a liquid front in contact with a solid substrate is determined by the interfacial forces of the participating phases (gas/liquid, gas/solid, liquid/solid, liquid/liquid). Wettability of a surface by a liquid is the actual process of spreading. One can qualitatively determine the wetting with the contact angles i.e. when the contact angles are low this means good wetting, and when the contact angles are high this means non-wetting conditions. A quantitative measure of wetting is the spreading coefficient, which allows us to predict whether a liquid spontaneously spreads on the surface of a solid or a second liquid. The spreading coefficient is the energy difference between the solid substrate with the contacting gas and liquid phases. Contact angle is the primary parameter for determining spreading; suitable instruments from Attension for this are the Theta,Theta Lite and Sigma701/700 tensiometers.