Hsv color space
HSV color space is a way of describing colors in terms of hue, saturation and value. It is roughly equivalent to a cone, or sphere, where hue is the distance around the circumference, saturation is the distance from the center and value is the height. Saturation is roughly how pale a color is, a very pale colour will have a low saturation. Value is how bright the color is and hue is how far round the colour circle it is. All colors with a value of 0 are black regardless of their other components and those with 0 saturation are grayscale regardless of the hue.