A soft drink is a drink that typically contains carbonated water, a sweetener, and a natural or artificial flavoring.
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 considered non-alcoholic. Fruit juice, tea, and other non-alcoholic beverages are technically soft drinks by this definition but are not generally referred to as such.