The printing process that reproduces colors by combining,
cyan, magenta, yellow and black. If you look through a magnifying glass,
you'll see that the printed image consists of dots in these four colors.
These dots are printed on top of each other, next to each other or just
close to each other, depending on the color and tonal values wanted.
For example; by printing a blue dot over a yellow dot will give you
green etc. To created the shadows in the image, all the colors (with
or without black - depending on the intensity of the shadow) will be
printed on top of each other to create a dark brownish color. The closer
the colored dots are printed to each other, the darker it will appear.
The further apart the colored dots are printed from each other, the
lighter that part of the image will appear.