Collage generally refers to two-dimensional works created from an assemblage of different materials, although the distinction between collage and assemblage (which refers to three-dimensional works) can be quite fluid. Though long a popular pastime amongst scrapbookers, the technique’s art-historical beginnings are generally traced back to one of its earliest appearances in Western art: Pablo Picasso’s Still Life with Chair Caning of 1912, which incorporated real-life objects into a work of art for the first time. In the collage, a printed oilcloth simulated chair caning and a piece of rope functioned as both a frame and the border of a café table. Collage was an assault on painting and its proposal of imaginary space as well as the proper materials of art. For example, Kurt Schwitters' collages and assemblages brought the detritus of street life and modern life's printed ephemera—ticket stubs, newspapers, postage stamps—into the realm of high art. The development of collage in art ran parallel to experiments in poetry and literature in the early 20th century, where aesthetic principles of fragmentation, reassembly, and multiple meanings reflected the rapid societal and technological changes ushered in by modernism and urbanization.