HSL Color Picker can help you to describe meaningful relationships between colors. Give this brown color, hsl(36, 73%, 10%), it’s clear that if we desaturate 40 steps and lighten 70 steps we get hsl(36, 33%, 80%), a cream color. 

it feels more natural to work with HSB (Hue, Saturation, Brightness) than RGB or CMYK. Now, with CSS3 we can use HSL which is actually quite different than HSB.