An American modernist artist who spent most of his career in Paris. He was a significant contributor to the Dada and Surrealist movements, although his ties to each were informal. He produced major works in a variety of media but considered himself a painter above all. He was best known in the art world for his avant-garde photography and he was a renowned fashion and portrait photographer.

A son of Russian immigrants in Philadephia, he studied architecture and then turned to painting. In 1915 he began to photograph his own paintings while also making a living from portrait and fashion photography. In 1915 he befriended Duchamp, and followed him to Paris in 1921. From 1918 to 1920, he formulated his ideas with the aid of objects, transforming human bodies into mechanical constructions and, vice versa, animating everyday things. Beginning in 1922 he developed 'rayography', a process for which no camera was required, involving placing objects on photo paper and exposing thems, creating shadowy forms and patterns. His collection of rayograms is considered a photographic counterpart to Breton's automatic writing. Between 1923 and 1929, he made five films, but his hoped-for career as a film-maker foundered on the Surrealists' lack of recognition and on the predominance of the films of Luis Buñuel and Salvador Dalí.