While many readers now associate the term "concrete poetry" with poems whose outlines depict a recongnizable shape—John Hollander's collection Types of Shape, for example—the ideas behind concrete poetry are much broader. In essence, works of concrete poetry are as much pieces of visual art made with words as they are poems. Were one to hear a piece of concrete poetry read aloud, a substantial amount of its effect would be lost.
European artists Max Bill and Öyving Fahlström originated the term in the early 1950s, and its early methods were described in the Brazilian group Noigandres' manifesto "Pilot Plan for Concrete Poetry." During this period, concrete poems were intended to be abstract and without allusion to an existing poem or identifiable shape. An interest in ideograms—and the notion that words themselves could be ideograms—accompanied the typographical innovations developed by these artists and by such visual writers as E. E. Cummings and Ezra Pound.
As the movement spread across the continents, reaching the height of its popularity in the 1960s, concrete poetry became less abstract and was adopted by many conventional poets as a specific poetic form rather than a combination of literature and visual art. In response, some artists adopted the term "poesia visiva" to describe more experimental fusions of word and image. As with much visual art, concrete poetry and poesia visiva now use photography, film, and even soundscapes in combination with letters and words to achieve new and startling effects.
An extremely well-curated website that successfully addresses the synthesis of literary, visual, and sonic arts can be found at UbuWeb. The Sackner Archive of Concrete and Visual Poetry, located in Florida, maintains a brief, informational website as well.