There is a tendency to utilize underground space for the less ornamental purposes of civilization; there is the Metropolitan Railway in London, for instance, there are new electric railways, there are subways, there are underground workrooms and restaurants, and they increase and multiply.
Polystyrene can be naturally transparent, but can be colored with colorants. Uses include protective packaging (such as packing peanuts and CD and DVD cases), containers (such as clamshells), lids, bottles, trays, tumblers, and disposable cutlery.
Most convenience-size beverage bottles sold in the United States are made from polyethylene terephthalate (PET). PET has become the material of choice for bottled beverages because it is lightweight and shatter resistant, and PET has been extensively tested for safety. Bottles made with PET are widely used for everything from water and fruit juice to soft drinks and even beer.