Tea is the second most popular beverage in the world (the most popular is water). It is made by steeping processed leaves, buds or twigs of the tea bush Camellia sinensis in hot water for a few minutes. The processing can include oxidation (fermentation), heating, drying and the addition of other herbs, flowers, spices and fruits.
There are four types of true tea: black tea, oolong tea, green tea, and white tea. The term herbal tea usually refers to infusions of fruit or herbs such as rosehip tea, chamomile tea and Jiaogulan that contain no tea leaves. (Alternative terms for herbal tea that avoid the misleading word "tea" are tisane and herbal infusion.) This article is concerned exclusively with preparations and uses of the tea plant Camellia sinensis.
Tea is a natural source of caffeine, theophylline, and antioxidants, although it has almost no fat, carbohydrates, or protein. It has a cooling, slightly bitter and astringent taste. Iced Tea has been popular in North America since the 1904 St. Louis World's Fair.