Butane is highly flammable, colorless, easily liquefied gases & Butane is a gas at room temperature and atmospheric pressure.
Normal butane can be used for gasoline blending, as a fuel gas, either alone or in a mixture with propane, and as a feedstock for the manufacture of ethylene and butadiene, a key ingredient of synthetic rubber. Isobutane is primarily used by refineries to enhance (increase) the octane number of motor gasoline.
Very pure forms of butane, especially Isobutane, can be used as refrigerants and have largely replaced the ozone layer-depleting halomethanes, for instance in household refrigerators and freezers. The system operating pressure for butane is lower than for the halomethanes, such as R-12, so R-12 systems such as in automotive air conditioning systems, when converted to butane will not function optimally.
Butane is also used as lighter fuel for a common lighter or butane torch and is sold bottled as a fuel for cooking and camping.