What is the defining characteristic of Cubism?

A multifaceted and enigmatic style of modern art, Cubism is defined primarily by its break with art historical tradition. Launched by Picasso and Braque in the first decade of the twentieth-century in Paris, Cubism posed a challenge to formal, material and representational convention in art, as well as traditions of display. Indeed, a Cubist painting can be identified by its use of abstraction. Contrary to the high-naturalism central academic precedents of representation, objects and figures depicted in Cubist paintings are typically fragmented. This is evidenced in Picasso's painting, 'Les Demoiselles d'Avignon', in which the women are represented using shard-like, angular shapes. This painting also demonstrates Cubism's attack on representational convention, rejecting traditions of the beautiful, divine female nude.
Furthermore, Cubism also departs from traditional media. Picasso's work, 'Guitar' uses everyday materials such as cardboard, wire and metal to represent a guitar in high-relief . The use of found materials is particularly radical in its overt rejection of expensive and prestigious academic sculptural materials such as bronze and marble. Furthermore, Cubism blends the boundary between genres, often incorporating three-dimensional materials into painting. In this way, I have demonstrated that the radical break with artistic convention is the defining characteristic of Cubism.