"Words have appeared in visual art since classical times, but until the modern era their use was generally restricted to a few specific functions. In the early twentieth century, the Cubists Braque and Picasso began using words in their paintings and collages in entirely new ways, and their innovation was quickly adopted by other artists. Words, phrases, and sentences were subsequently used by visual artists for a variety of purposes -- to refer to popular culture, to pose verbal puzzles, to engage with philosophy and semiotics, and for political and social commentary. Throughout the century, the use of language in visual art was dominated by conceptual artists, and the increasing role of language over time was symptomatic of the fact that visual art was progressively intended less as an aesthetic product, to be looked at, and increasingly as an intellectual activity, to be read. The prominence of language is yet another way in which the visual art of the twentieth century differs from all earlier periods, as a result of the increasingly extreme practices of conceptual artists after the development of a competitive market for advanced art in the late nineteenth century freed them from the constraints that had previously been imposed by governments and other powerful patrons"--National Bureau of Economic Research web site.