Gasoline tax is a tax on the purchase of gasoline. This tax, commonly known as a motor fuel tax, is paid chiefly by road and highway users. Off-the-highway users of motor fuel, including the operators of airplanes, some boats, and farm machinery, also pay the tax but get a partial refund. Diesel fuel and other types of fuels are also taxed. The United States government and all the states levy motor fuel taxes. The governments use the revenues to build and improve roads.