Oil refineries often produce intermediary products known as petrochemicals. The oil refining process produces many byproducts that can be refined further into useful states. Through a process known as cracking, feeds of gaseous or liquid petroleum byproducts are combined with steam and heated in an oxygen free environment to produce ethane and polyethane. Ethane and polyethane are sold to manufacturing supply chains to create consumer goods. Petrochemicals like ethane and polyethane are the basis for many modern plastics, detergents, fertilizers, and more.