Oranges are probably the largest citrus crop in the world and are best known for their vitamin C properties. Oranges originated in Southeast Asia and are widely grown in the warmer climates throughout the world. Primarily there are three varieties of oranges; the sweet orange, the sour orange and the mandarin orange or better known as a tangerine. The United States is known to produce the sweet variety, while Spain is known to produce the sour range.The sweet ranges include the Blood, Jaffa, Hamlin, Navel, Pineapple and Valencia orange, while the sour variety is known as Seville and is commonly used in liquors and jams. One hundred grams of oranges contain 47 calories, 12 grams of carbohydrates, 1 gram of protein and absolutely zero fat. One hundred grams of oranges also contain 89% of the recommended dietary allowance (RDA) of vitamin C, 4% of vitamin A, 4% of calcium as well as 1% of iron. Oranges are full of bioflavonoids and carotenoids, which fight off cancer. They also contain disease- fighting phytochemicals which help to combat heart disease. According to FAO (the Food and Agriculture Organisation of the United Nations) Corporate Statistical Database (FAOSTAT), the top ten producers of oranges in 2005 were Brazil, USA, Mexico, India, China, Spain, Italy, Iran, Egypt and Pakistan. Oranges have many uses and are used in the production of orange juice, chemicals used to condition wooden furniture, perfume and jams, while gardeners have used the orange peels or rind as a slug repellent.