From the Sanskrit "nagarunga" which means "fruit loved by elephants." The word became "narandj" in Arabic.
The fruit grows on orange trees, which may reach 5 m in height.
The warmer the growing conditions, the thinner the orange's peel will be.

There are numerous varieties of oranges:

bitter oranges - Citrus aurantium
(bigarade, Seville orange) used for sauces, jellies and marmalades

sweet oranges - Citrus sinensis
(Valencia, blood oranges), excellent for juice

Navel orange - also known as the Washington, Riverside or Bahia navel
Navel oranges are almost always seedless, and tend to be larger than other sweet oranges. Excellent for sectioning into "supremes."

The Valencia or Murcia orange
It is one of the sweet oranges used for juice extraction. It is a late-season fruit, and therefore a popular variety when the navel oranges are out of season. For this reason and to be one of the venues of the 1982 Football World Cup the orange was choosed to be the official mascot called "Naranjito" wearing the colours of the Spain soccer team uniform.

The blood orange
It has streaks of red in the fruit, and the juice is often a dark burgundy color.

The mandarin orange
It is similar, but smaller and sweeter, and the navel orange.