Hue[h] is a graphics directive which specifies that graphical objects which follow are to be displayed, if possible, in a color corresponding to hue h.
Hue[h, s, b] specifies colors in terms of hue, saturation and brightness.
The parameters h, s and b must all be between 0 and 1. Values of s and b outside this range are clipped. Values of h outside this range are treated cyclically.
As h varies from 0 to 1, the color corresponding to Hue[h] runs through red, yellow, green, cyan, blue, magenta, and back to red again.
Hue[h] is equivalent to Hue[h, 1, 1].
On monochrome displays, a gray level based on the brightness value is used.
The end of the Graphics Gallery shows examples of colors generated with various Hue specifications.
See The Mathematica Book: Section 1.9.7 and Section 2.9.3.
See also: RGBColor, GrayLevel, CMYKColor.
Related package: Graphics`Colors`.