Cubism was an early 20th century avant-garde art movement pioneered by Pablo Picasso and Georges Braque that revolutionized painting. It emphasized depicting objects from multiple perspectives and using geometric forms rather than realistic detail. There were three periods of Cubism: Early Cubism depicted the whole structure of objects combining viewpoints; Analytic Cubism broke down subjects into facets showing different viewpoints; and Synthetic Cubism introduced collage with painting fragments.