Color is EVERYTHING, regardless if used in web design or print design. Color conveys emotions, feelings, moods, and can even determine whether or not you make a purchase, or believe in a brand. It's mighty powerful. In my studio, I surround myself with vibrant colors for stimulation, and also out of love. In my home, it's more of a neutral palette with a splash of soft green and blue hues. I love a peaceful, calming environment when I'm relaxing there.
I digress...
These guys at Kissmetrics created a beautiful infographic that breaks it down to basics - what I learned my freshman year in college many moons ago. I share it for a few reasons 1) I love infographics, especially nicely designed/illustrated ones; 2) I find color theory fascinating; and 3) my clients need to understand why I choose the colors I do for their brand.