Aluminium foil is aluminium prepared in thin sheets (on the order of .03 millimeters in thickness). As a result of this, aluminium foil is extremely pliable, and can be bent or wrapped around objects with ease.
Aluminium foil is widely sold into the consumer market, usually in rolls of around 50 centimeters width and several metres in length. It is used for wrapping food in order to preserve it, for example when storing leftover food in a refrigerator (when it serves the additional purpose of preventing odour exchange), when taking sandwiches on a journey, or when selling some kinds of take-away or fast food; Mexican restaurants in the United States, for example, typically provide takeaway burritoss wrapped in aluminium foil.
The extensive use of aluminium foil has been criticised by environmentalists because of the high resource cost of extracting aluminium.