Detergent is a substance that is used to remove dirt, grease or other unwanted materials from surfaces. It typically contains surfactants which lower the surface tension between two liquids and allows them to mix more easily. Detergents are commonly used in laundry products for cleaning clothes, as well as in soaps and cleaners for washing dishes, surfaces or even hands. The term "detergent" can also refer to a substance that discourages certain behaviors or actions, such as the use of chemical weapons being seen as a deterrent against their use in warfare.