Ginger cultivation began in South Asia and has since spread to East Africa and the Caribbean. It is sometimes called root ginger to distinguish it from other things that share the name ginger.
The English name ginger comes from French: gingembre, Old English: gingifere, Medieval Latin: ginginer.

Ginger contains up to three percent of a fragrant essential oil whose main constituents are sesquiterpenoids, with (-)-zingiberene as the main component. Smaller amounts of other sesquiterpenoids (β-sesquiphellandrene, bisabolene and farnesene) and a small monoterpenoid fraction (β-phelladrene, cineol, and citral) have also been identified.
Ginger has a sialagogue action, stimulating the production of saliva, which makes swallowing easier.
Culinary Use
Young ginger rhizomes are juicy and fleshy with a very mild taste. They are often pickled in vinegar or sherry as a snack or just cooked as an ingredient in many dishes. They can also be steeped in boiling water to make ginger tea, to which honey is often added; sliced orange or lemon fruit may also be added. Ginger can also be made into candy.
Mature ginger roots are fibrous and nearly dry. The juice from old ginger roots is extremely potent, and is often used as a spice in Indian recipes, and is a quintessential ingredient of Chinese, Japanese and many South Asian cuisines for flavoring dishes such as seafood or goat meat and vegetarian cuisine. Ginger acts as a useful food preservative.
Fresh ginger can be substituted for ground ginger at a ratio of 6 to 1, although the flavors of fresh and dried ginger are somewhat different. Powdered dry ginger root is typically used as a flavoring for recipes such as gingerbread, cookies, crackers and cakes, ginger ale, and ginger beer. Candied ginger is the root cooked in sugar until soft, and is a type of confectionery.
Fresh ginger may be peeled before eating. For longer-term storage, the ginger can be placed in a plastic bag and refrigerated or frozen.
Regional Use

In Bangladesh, ginger is called Aadha and is finely chopped or ground into a paste to use as a base for chicken and meat dishes alongside shallot and garlic.
In the Philippines, ginger is called luya and is used as "candy" when there is sore throat or hoarse voice.
In Burma, ginger is called gyin. It is widely used in cooking and as a main ingredient in traditional medicines. It is also consumed as a salad dish called gyin-thot, which consists of shredded ginger preserved in oil, and a variety of nuts and seeds.
In Indonesia, a beverage called wedang jahe is made from ginger and palm sugar. Indonesians also use ground ginger root, called jahe, as a common ingredient in local recipes.
In Nepal, ginger is called "aduwa" and is widely grown and used throughout the country as a spice for vegetables, used medically to treat cold and also sometimes used to flavor tea.
In Vietnam, the fresh leaves, finely chopped, can also be added to shrimp-and-yam soup as a top garnish and spice to add a much subtler flavor of ginger than the chopped root.
In Japan, ginger is pickled to make beni shoga and gari or grated and used raw on tofu or noodles. It is also made into a candy called shoga no satozuke.
In the traditional Korean kimchi, ginger is finely minced and added to the ingredients of the spicy paste just before the fermenting process.
In Western cuisine, ginger is traditionally used mainly in sweet foods such as ginger ale, gingerbread, ginger snaps, parkin, ginger biscuits and speculaas. A ginger-flavored liqueur called Canton is produced in Jarnac, France. Green ginger wine is a ginger-flavored wine produced in the United Kingdom, traditionally sold in a green glass bottle. Ginger is also used as a spice added to hot coffee and tea.

On the island of Corfu, Greece, a traditional drink called tsitsibira, a type of ginger beer, is made. The people of Corfu and the rest of the Ionian islands adopted the drink from the British, during the period of the United States of the Ionian Islands.
In Arabic, ginger is called zanjabil, and in some parts of the Middle East, ginger powder is used as a spice for coffee and for milk, as well. In Somaliland, ginger is called sinjibil, and is served in coffee shops in Egypt.
In the Ivory Coast, ginger is ground and mixed with orange, pineapple and lemon to produce a juice called nyamanku.
Medicinal use
The medical form of ginger historically was called Jamaica ginger; it was classified as a stimulant and carminative and used frequently for dyspepsia, gastroparesis, slow motility symptoms, constipation, and colic. It was also frequently employed to disguise the taste of medicines. Ginger is on the FDA's "generally recognized as safe" list, though it does interact with some medications, including warfarin. Ginger is contraindicated in people suffering from gallstones as it promotes the production of bile. Ginger may also decrease pain from arthritis, though studies have been inconsistent, and may have blood thinning and cholesterol lowering properties that may make it useful for treating heart disease. An acute overdose of ginger is usually in excess of about 2,000 milligrams per kilogram, dependent on level of ginger tolerance, and can result in a state of central nervous system over-stimulation called ginger intoxication or colloquially the "ginger gitters".
Ginger compounds are active against a form of diarrhea which is the leading cause of infant death in developing countries. Zingerone is likely to be the active constituent against enterotoxigenic Escherichia coli heat-labile enterotoxin-induced diarrhea.

Folk medicine

Regional medicinal use
- In Burma, ginger and a local sweetener made from palm tree juice (htan nyat) are boiled together and taken to prevent the flu.
- In China, ginger is included in several traditional preparations. A drink made with sliced ginger cooked in water with brown sugar or a cola is used as a folk medicine for the common cold.
- In Congo, ginger is crushed and mixed with mango tree sap to make tangawisi juice, which is considered a panacea.
- In India, ginger is applied as a paste to the temples to relieve headache, and consumed when suffering from the common cold. Ginger with lemon and black salt is also used for nausea.
- In Indonesia, ginger ("jahe" in Indonesian) is used as a herbal preparation to reduce fatigue, reducing "winds" in the blood, prevent and cure rheumatism and control poor dietary habits.
- In the Philippines a traditional health drink called "salabat" is made for breakfast by boiling chopped ginger and adding sugar; it is considered good for a sore throat.
- In the United States, ginger is used to prevent motion and morning sickness. It is recognized as safe by the Food and Drug Administration and is sold as an unregulated dietary supplement.
- In Peru, ginger is sliced in hot water as an infusion for stomach aches as "infusión de Kión"
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Reference: http://en.wikipedia.org/wiki/Ginger