An industrial lubricant is a substance that is used to reduce friction between surfaces that are in mutual contact with each other. It also transmits forces and acts as a coolant between the surfaces. The property of reducing friction is called lubricity. Lubricants contain around 90% base oil (crude oil) and less than 10% additives. Synthetic liquids that include polyolefins, esters, silicones, fluorocarbons, and others are often used as base oil. The additives play an important role in reduction of friction and wear and offer increased viscosity, resistance to corrosion and oxidation, aging or contamination, and others.