ke it easier to encode data variables (e.g., diamond clarity) as visual properties (e.g., color). By default, these arguments map values of a data variable to a visual range defined by the plural form of the argument. For example, in the bottom panel of <a href="overview.html#fig:intro-defaults">2.1</a>, <code>color</code> is used to map each level of diamond clarity to a different color, then <code>colors</code> is used to specify the range of colors (which, in this case, the <code>"Accent"</code> color pa