The two-liter bottle is a common container for soft drinks. These bottles are produced from polyethylene terephthalate, also known as PET plastic, using the blow molding process. Bottle labels consist of a printed, tight-fitted plastic sleeve. A resealable screw-top allows the contents to be used at various times while retaining carbonation.
In the United States, the two-liter bottle is one of the few cases where a product is sold by a round number of metric units. Since very few other beverages are sold in this exact quantity, the term "two-liter" in American English almost invariably refers to a soft drink bottle. Other common metric sizes for plastic soft drink bottles include 500 milliliters, 1 liter and 3 liters.
A soft drink (also called soda, pop, coke, soda pop, fizzy drink, tonic, seltzer, mineral, sparkling water, lolly water or carbonated beverage) is a beverage that typically contains water (often, but not always, carbonated water), usually a sweetener and usually a flavoring agent. The sweetener may be sugar, high-fructose corn syrup, fruit juice, sugar substitutes (in the case of diet drinks) or some combination of these. Soft drinks may also contain caffeine, colorings, preservatives and other ingredients.
Soft drinks are called "soft" in contrast to "hard drinks" (alcoholic beverages). Small amounts of alcohol may be present in a soft drink, but the alcohol content must be less than 0.5% of the total volume if the drink is to be considered non-alcoholic. Fruit juice, tea and other such non-alcoholic beverages are technically soft drinks by this definition but are not generally referred to as such.