Avant-garde is a military term referring to a group of soldiers who attack in advance of the main body, used as a metaphor for any form of art that challenges artistic conventions and is, as were, ahead of its time. It is the advanced group in any field, especially in the visual, literary, or musical arts, whose works are characterized chiefly by unorthodox and experimental methods. It is frequently characterized by aesthetic innovation and initial unacceptability.
It first came into vogue in the latter part of the 19th century in France. It is sometimes used as a synonym for modernism, but while there is an element of truth in this it is misleading too, inasmuch that Avant-garde does not imply either a particular period or style. More generally, though, Avant-garde is used in critical theory as a codeword for the problem of the new, which in the era of postmodernism is considered especially acute because it is thought all possible forms of artistic experimentation have been tried.
The concept of avant-garde refers primarily to artists, writers, composers, and thinkers whose work is opposed to mainstream cultural values, and often has a trenchant social or political edge. The notion of avant-garde enshrines the idea that art should be judged primarily on the quality and originality of the artist’s vision and ideas. So it is, therefore, an ontological as well as artistic or historical problematic in that it contains the question of its own possibility: what does it take to be absolutely new? For this reason, books about the Avant-garde tend to focus on its theory, rather than its praxis.
Also read: What is Aestheticism movement?