Pointillism has been around for a long time. Seurat brought this technique into common use in the early 19th century with the Impressionists. It can be used exclusively on its own or combined with other techniques, as I do in my work.
Points or dots of different colors can be placed in proximity to make a new color; for instance, a dot of red placed beside a dot of blue causes the mind to see purple.
Complementary colors can be used to darken or highlight. Ultimate digital pointillism is exemplified by the color T.V. set where various combinations of dots–red, blue, and green–create all the colors.