Plastics are durable, lightweight materials that were invented in 1909. They are normally made from oil and natural gas. Using plastics to replace packaging materials such as metal and glass has allowed manufacturers to make packages that are more efficient. For example to bottle eight gallons of a beverage would take only two pounds of plastic but would take three pounds of aluminum, eight pounds of steel and 27 pounds of glass. The lightweight of plastic packaging helps reduce transportation costs. It takes fewer trucks to transport plastic compared to metal or other materials. Fewer trucks mean less fuel usage and therefore less air pollution from truck exhaust.