ABSTRACT
In this chapter, we shall discuss equilibrium liquid shapes on solid substrates, which demands equilibrium of liquid-vapor, liquid-solid, and vapor-solid. Not always do authors take into account all the three equilibria. The vapor-solid equilibrium determines the presence of adsorbed liquid layers on solid surfaces for both complete and partial wetting. Even at this moment, we and everything around are covered by a thin water film. The thickness of aqueous films depends on the humidity in the room, and the adsorption is exactly at equilibrium with the surrounding humidity, no matter how low or high.
