Cubism was an early 20th century avant-garde art movement that revolutionized European painting and sculpture. Led by Pablo Picasso and Georges Braque, Cubism involved analyzing subject matter into geometric facets and reassembling them in an abstracted form rather than using traditional perspective and modeling of light and shadow. Cubism had two phases - Analytical Cubism from 1907 to 1912 focused on reducing forms to basic geometric shapes and limited color, while Synthetic Cubism from 1912 to 1919 incorporated collage and a broader range of colors.