Orange is vibrant.
It’s a combination of red and yellow so it shares some common attributes with those colours.
It denotes energy, warmth, and the sun. But orange has a bit less intensity or aggression than red, calmed by the cheerfulness of yellow.
As a warm colour orange is a stimulant — stimulating the emotions and even the appetite.
Orange can be found in nature in the changing leaves of autumn, the setting sun, and the skin and meat of citrus fruit.
Orange brings up images of autumn leaves, pumpkins, and (in combination with Black) Halloween. It represents the changing seasons so in that sense it is a colour on the edge, the colour of change between the heat of summer and the cool of winter.
Yellow is sunshine.
It is a warm colour that, like red, has conflicting symbolism. On the one hand it denotes happiness and joy but on the other hand yellow is the colour of cowardice and deceit.
Yellow is one of the warm colours. Yellow is cheerful and yellow is mellow.
For years yellow ribbons were worn as a sign of hope as women waited from their men to come marching home from war. Today, they are still used to welcome home loved ones. Its use for hazard signs creates an association between yellow and danger, although not quite as dangerous as red.
Although it can work as the primary colour, yellow often works best as a companion to other colours. Use bright yellow to create excitement when red or orange may be too strong or too dark. Yellow can be perky.