The colour orange occurs between red and yellow in the visible spectrum at a wavelength of about 585–620 nanometres. It is a pure chroma on the color wheel.

The Oxford English Dictionary has a citation for orange the fruit (spelled “orenge”) from 1044. Orange as the name of a color, however, didn’t come on to the scene for several centuries after that. During the political upheavals of the 16th and 17th centuries, however, orange became a natural pick for a team color.

At the time when the princes of Orange in Ireland were making names for themselves, the orange itself was a relatively recent arrival in Europe from India, where it is thought to have originated. In Spain (one of its stops along the way) the word for “orange” is “naranja.” Somehow the initial “n” seems to have come unstuck as the word came into English; what should have been “a norange” became “an orange.”

As Alexander Thuroeau mentions in his dissortation on the colour, in the midieval times staining glass was a difficult art to get yellow and red to not become tarnished into an ochre hue of ‘no range’ of an actual color that was commonly recognized and accepted in the era. Now it is embraced for it’s own asceticism.

In history
Before the orange fruit was introduced to the English-speaking world, the colour was referred to (in Old English) as geoluhread, which transliterates into Modern English variously as yellow-red, yellowred, or yellored (all pronounced the same).

the was introduced to the -speaking world, the colour was referred to (in ) as , which into variously as , , or (all pronounced the same).

In painting
With natural colouring materials such as paints or crayons, orange is a secondary colour that can be derived from primary colours by mixing red (or more accurately, magenta) and yellow.

Orange in Human Culture
In English heraldry, orange denotes strength, honour, generosity, and prosperity. However, its use as a heraldic tincture is relatively rare.
Orange is the national colour of The Netherlands, because its royal family used to own the principality of Orange (the title is still used for Dutch heir apparent). It is the colour of choice for many of the national sports teams and their supporters. The nickname of the Dutch national soccer (football) team is Oranje, the Dutch word for orange. In the modern flag of the Netherlands, red substitutes the original orange, but on royal birthdays the flag has an additional orange banner. Most geographical usages of the word orange can be traced back to Dutch maritime power in the 17th century. In Ireland the use of orange dates from the reign of William of Orange, the Protestant English king and a Dutch stadholder.
Orange signifies Protestantism in Northern Ireland (see Orange Order), and to a lesser extent in the Republic of Ireland (the orange part of whose flag represents the Protestant population) and Hinduism in India and Sri Lanka.
Orange has become a colour symbolising opposition around the world.
Orange was the rallying colour of the 2004–2005 Orange Revolution in Ukraine.
Orange is used as a rallying colour by Jewish settlers in the Gaza Strip who oppose the Gaza Pull-Out plan.
Native American Indians associated the color orange with kinship

Orange is very blatant and vulgar. It makes you immediately start having feelings.–Wolf Kahn