Cubism was the first abstract art movement developed by Pablo Picasso and Georges Braque in the early 20th century. They were influenced by Paul Cézanne's geometric shapes and multiple perspectives in paintings as well as African masks. Cubist works depict objects from various angles simultaneously on a two-dimensional surface using geometric forms rather than realistic rendering. Early Cubist works incorporated collage elements, while later analytical Cubism reduced forms to basic shapes and synthetic Cubism reintroduced more color and discernible subjects. Other notable Cubist artists included Juan Gris, Fernand Léger, Robert Delaunay, and Marcel Duchamp.