Yep there is such a thing as a psychology of colors. It mostly practiced in commercial establishments such as supermarkets and restaurants. For example, the reason why those popular fast food chains choose yellow, orange, and red for their color theme is because those colors make you hungry! Hmm, if this is the case, then why not employ the same science to your own Web site?

Here’s the color code which you can mix and match:

White: Easy on the eyes, perfection, peace, purity, sense of professionalism
Red: warmth, hunger, and excitement
Yellow: Happiness, vibrant
Green and blue: Calmness, content
Black, brown, grey: Serious, Somber

Source: Free Webmaster Tools