Subtractive Colour systems start with light, presumably white light. Coloured inks, paints, or filters between the viewer and the light source or reflective surface subtract wavelengths from the light giving it colour. If the incident light is other than white, our visa mechanisms are able to compensate well, but not perfectly often giving a flawed impression of the "true colour of the surface.
Additive Colour is colour created by mixing light of two or more different colours. Red, Green, and Blue are the additive Primary Colours normally used in additive colour system. Additive colour is in contrast to subtractive colour, in which colours are created by subtracting parts of the spectrum of light present in ordinary white light, by means of coloured pigments or dyes, such as those in paints, inks and the three dye layers in typical colour photographs on films.
Red is the colour of fire and blood, so it is associated with energy, war, danger, strength, power, determination as well as passion, desire and love.
Yellow is the colour of sunshine. It's associated with joy, happiness, intellect and energy.
Green is the colour of nature. It symbolises growth, harmony, freshness, and fertility. Green has strong emotional correspondence with safety.
Blue is the colour of the sky and sea. It is often associated with depth and stability. It symbolises trust, loyalty, wisdom, confidence, intelligence, faith, truth and heaven.
Magenta combines the stability of blue and the energy of red. Magenta is associated with royalty. It symbolises power, nobility, luxury, and ambition. Magenta is associated with wisdom, dignity, independence, creativity, mystery, and magic.
White is associated with light, goodness, innocence, purity and virginity. It is considered to be the colour of perfection.
