Hue, saturation and lightness

HSL is way of representing colors.

Hue is the angle of the color and the color wheel (imagine the rainbow represented in a circle)

Saturation is the intensity of a specific hue. A highly saturated hue has a vivid, color, while a less saturated hue appears more grey.

Llightness is the perceived amount of light in color. A high value tends towards white, and a low one towards black.