Stochastic printing, also called frequency modulation (FM), staccato, or diamond screening, uses small (10, 20 or 25 Micron), equal size dots in a random pattern.  To vary color and contrast in an image the density of the dot clusters change.  Where the dots are dense, there is more color; where they are sparse, there is less color.  With stochastic printing you get an image that is closer to continuous tone.

Some of the benefits of stochastic printing over conventional printing methods are that the images are sharper, tones and colors are consistent, there are no screen angle moirés, and there is a wider reproducible color gamut.  The smaller dot also reduces the impact of variability and imperfections in inks and papers used on press.