Cleaning agents are used in a variety of applications to dissolve, remove, or clean unwanted materials from surfaces or substrates. They can be organic or inorganic compounds, and can be used in liquid or gaseous form. It is differentitated between water-based and solvent cleaner. A solvent cleaner or solvent degreaser uses a liquid to dissolve a soil. It can utilize one solvent, a variety of solvents, or a combination of several solvents and compounds to maximize performance parameters for a specific application. Solvents can be broken down into their basic functional compounds, such as alcohols, ketones, aliphatic hydrocarbons, etc. Water is also a solvent and is a subsection of the solvent category. Water-based degreasers utilize water as the primary solvent, but can also include any of the solvents mentioned above, plus detergents, pH modifiers, builders, chelating agents, and a variety of other compounds.