Oranges originated in south-east Asia, in either India, Vietnam or southern China. The fruit of Citrus sinensis is called sweet orange to distinguish it from Citrus aurantium, the bitter orange. Today oranges are widely grown in warm climates worldwide, and the flavors of oranges vary from sweet to sour. The fruit is commonly peeled and eaten fresh, or squeezed for its juice. It has a thick bitter rind that is usually discarded, but can be processed into animal feed by removing water, using pressure and heat.

Orange juice is one of the commodities traded on the New York Board of Trade. Brazil is the largest producer of orange juice in the world, followed by the USA. Juice is made by squeezing the fruit on a special instrument called a "juicer" or a "squeezer". The juice is collected in a small tray underneath. This is mainly done in the home, and in industry will be done on a much larger scale.

Sweet orange oil consists of about 90% d-Limonene, a solvent used in various household chemicals, such as to condition wooden furniture, and along with other citrus oils in grease removal and as a hand-cleansing agent.

*IARC Monographs on the evaluation of carcinogenic risks to humans 1999, 73, 307-27