Surfactants constitute the most important group of detergent components. They are wetting agents that lower the surface tension of a liquid, allowing easier spreading, and lower the interfacial tension between two liquids. The word surfactant derives from the contraction of the terms surface-active-agents and covers a group of molecules which are able to modify the interfacial properties of the liquids (aqueous or non-aqueous) in which they are present one.