Gasoline  /ˈɡæsəliːn/, or petrol  /ˈpɛtrəl/, is a transparent petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain ethanol as an alternative fuel. In North America the term "gasoline" is often shortened in colloquial usage to "gas" but some people use the term "petrol". Under normal ambient conditions its material state is liquid, unlike liquefied petroleum gas or "natural gas".