Lighters contain butane, a liquefied petroleum gas, as the fuel.
Other lighters, like cigarette lighters, contain a reservoir of lighter fluid, a liquefied flammable gas such as propane or butane, a valve, and an ignition device.
Butane is a hydrocarbon and a highly flammable, colorless, odorless, easily liquefied gas.
It is typically used as fuel for cigarette lighters and portable stoves, a propellant in aerosols, a heating fuel, a refrigerant, and in the manufacture of a wide range of products.