Of all forms of non-verbal communication, colour is the best way of conveying messages and meanings. It adds significant value as it vitalizes the visual message.
We associate certain ideas and feelings through colours and have learned to use them to convey messages for security or commercial reasons.

But colours may play very different roles depending on religious or cultural factors. White for instance is used as a symbol for purity in the western world, but seen as a symbol for mourning and death in the eastern world.