Tea is an infusion made by steeping processed leaves, buds, or twigs of the tea bush, Camellia sinensis, in hot water for several minutes. The processing can include oxidation, heating, drying, and the addition of other herbs, flowers, spices, and fruits. The four basic types of true tea are black tea, oolong tea, green tea, and white tea. The term "herbal tea" usually refers to infusions or tisane of fruit or herbs that contain no Camellia sinensis.

Tea is one of the most widely-consumed beverages in the world, second only to water. It has a cooling, slightly bitter, astringent flavor. It has almost no carbohydrates, fat, or protein. Tea is a natural source of the amino acid theanine, methylxanthines such as caffeine and theobromine, and polyphenolic antioxidant catechins (often referred to as tannins).

The word tea came into the English language from the Chinese word for tea, which is pronounced t� in the Min Nan spoken variant. The British English slang word "char" for "tea" arose from its Mandarin Chinese pronunciation "cha" with its spelling affected by British English arhotic dialect pronunciation.