The basic point about Louis's work and that of other Color Field painters, sometimes known as the Washington Color School in contrast to most of the other new approaches of the late 1950s and early 1960s, is that they greatly simplified the idea of what constitutes the look of a finished painting. They continued in a tradition of painting exemplified by Jackson Pollock, Barnett Newman, Clyfford Still, Mark Rothko, Robert Motherwell, and Ad Reinhardt. Eliminating gestural, compositional drawing in favor of large areas of raw canvas, solid planes of thinned and fluid paint, utilizing an expressive and psychological use of flat, and intense color and allover, repetitive composition. One of Louis's most important series of Color Field paintings were his Unfurleds. https://en.wikipedia.org/wiki/Morris_Louis