An herbal tea--that is, a tea with no tea leaves in it--is more properly called an infusion or tisane.
Tea is grown primarily in China, India, Sri Lanka, Taiwan, Japan, Nepal, and Kenya. (Note: in the tea trade, Sri Lanka and Taiwan are still referred to by their former names of Ceylon and Formosa, respectively.)
The four main types of tea are distinguished by their processing. Camellia sinensis is an evergreen shrub whose leaves, if not quickly dried after picking, soon begin to wilt and oxidize. This process resembles the malting[?] of barley, in that starch is converted into sugars; the leaves turn progressively darker, as chlorophyll breaks down and tannins are released. The next step in processing is to stop the oxidation process at a predetermined stage by removing the water from the leaves via heating. The term fermentation was used (probably by wine fanciers) to describe this process, and has stuck, even though no true fermentation happens.
Tea is traditionally classified into four main groups, based on the degree of fermentation undergone:
Teas are processed in two ways, CTC (crush, tear, curl) or orthodox. The CTC method is used for lower quality leaves that end up in tea bags and are processed by machines. This method is efficient and effective for producing a better quality product from medium and lower quality leaves. Orthodox processing is usually done by hand and is used for higher quality leaves. While the methods employed in orthodox processing differ by tea type, this style of processing results in the high quality loose tea sought after by many connoisseurs.
Black tea is usually named after the region of origin: Darjeeling, Assam, Ceylon, etc. Most green teas, however, have kept their traditional Japanese or Chinese names: Genmaicha[?] (玄米茶), Houjicha[?] (焙じ茶), Pouchong, etc. Green teas reputedly contain greater levels of antioxidants than black teas. White teas produce a delicate liquor that often retains a slight residual sweetness.
All types are sold as either "single" teas, meaning just one variety, or as blends. Adulteration and falsification are serious problems in the global tea trade; the amount of tea sold worldwide as Darjeeling every year greatly exceeds the annual tea production of Darjeeling, which is estimated at 11,000 metric tons.
There are various teas which have additives and/or different processing than "pure" varieties:
Products of some other plant species are also sometimes subsumed under the term tea.
Gautama Buddha is said to have discovered tea, when a falling tea leaf happened to land in his cup one day as he sat meditating in a garden. Another story has it that Bodhidharma cut his eyelids off so that he wouldn't fall asleep while meditating, and the first tea plants sprang up from the ground where he flung the severed eyelids.
The Boston Tea Party was an act of uprising in which Boston residents destroyed crates of British tea in 1773, in protest against the tax on tea. The high demand for tea in Britain caused a huge trade deficit with China. The British set up their own tea plantations in colonial India to provide their own supply. They also tried to balance the trade deficit by selling opium to the Chinese, which later led to the Opium War in 1838-1842.
The English word "tea" came from tê (茶) in Amoy (廈門 Xiamen, Fujian) from southern China. The British shipped tea from southern China to Europe via the sea route. One can tell by which trade route each culture was first exposed to tea by what name is used for tea in each language. For example, tea is known as "chai" in Russian, Farsi (Iranian), and some northern European languages. That indicates that they didn't get their tea via the sea. They most probably got their tea via the land route through the Silk Road in the north. Tea is called "cha" (茶) in Mandarin. In Ireland, or at least in Dublin, the term "cha" is sometimes used for tea, and "char" was a common slang term for tea throughout British Empire / commonwealth military forces in the 19th and 20th centuries, crossing over into civilian usage. Recently in the United States, many coffee houses have begun to serve a milky, sweet, spiced tea called "chai", loosely based on Indian recipes but much less spicy.
Tea is served both hot and iced, sometimes with lemon, milk, honey, or sugar. Recently, Boba milk tea from Taiwan has become an extremely popular drink among young people. This Asian fad spread to the USA in 2000, where it is generally called "bubble tea". (See news (http://www.cnn.com/2000/FOOD/news/11/27/bubble.tea.ap/))
Drinking tea is often a social event. Tea is also drunk throughout the day and especially in the morning to heighten alertness - it contains theophylline and caffeine (sometimes called "theine"). In Britain and Ireland, "tea" is not only the name of the beverage, but of a late afternoon light meal, called that even if the diners are drinking beer, cider, or juice. Frequently (outside the UK) this is referred to as "high tea", however in the UK high tea is an evening meal. The term evidently comes from the meal being eaten at the "high" (main) table, rather than the smaller table common in living rooms.
The best way to prepare tea is usually thought to be with loose tea in a teapot, rather than a teabag. Boiling water should be added, but the tea should not be allowed to steep for more than about five minutes (a process known as brewing or mashing in the UK): after that, tannin is released, which counteracts the stimulating effect of the theophylline and caffeine and makes the tea bitter. Some green teas are steeped for shorter periods, sometimes less than 30 seconds. Using a tea strainer[?] separates the leaves from the water at the end of the brewing time if a tea bag is not being used.
The water for black teas should be at the boiling point (100°C); water for green tea, according to most accounts, should be at 80 to 85°C. Preferably, the container in which the tea is steeped--the mug or teapot--should also be warmed beforehand (usually by swirling a little hot water around it then dumping it out) so that the tea does not immediately cool down.
Experienced tea-drinkers often insist that the tea should not be stirred around while it is steeping (sometimes called winding in the UK). This, they say, will do little to strengthen the tea, but is likely to bring the tannic acids out in the same way that brewing too long will do. For the same reason one should not squeeze the last drops out of a teabag: if you want stronger tea, use more leaves or bags.