In every period literature is considered modern (if compared to the former one). Anyway nowadays ”modernist” is literary production after World War I.

Modern era is marked by some historical and cultural events: the two  World Wars (1914-1918 and 1941-1945);  improvements in industry and technology and the rise of international corporations; global interconnections in transportation, communication and culture; the "Westernization" of the world with values set up in Europe and North America.

Modernist literature has born as reaction to Realism and Naturalism, that was aimed to describe external objects and events from middle class man’s point of view, supporting the superiority of rationalness and reason. Inside modernism is possible to indicate four literary movements also characterized by the contraposition to Realism. Those are: impressionism (that is concerned with the individual perception and psychological impressions the objects or events make on characters); expressionism (that wants to convey the inner vision, emotion and spiritual reality); surrealism (more interested in subconscious expression against rationality); nihilism (or absurdism that wants to point out the  absurd conditions of contemporary life). Anyway Modernism has in common with Realism an attention on the psychology of the individual and the consideration and the consideration of work of art.

Main features of modernist literature are: the use of images, symbols, and colloquial language; a particular consideration of this one (seen as a special medium to create work of art) and of literature (seen as a piece of art created by a genius); the importance given to form, style and technique; and the writer’s aim to change reader’s point of view of  the world and of the language.

"Postmodern" is contemporary literature of the last half of the 20^th century. Comparing it to modernist tradition, Post-modernism doesn’t have faith in beliefs of Western culture (because those are expression of only a part of human experience); doesn’t want to find out the truth of life (because there’s no more certainty); doesn’t try to explore  depth and interior meaning preferring to depict the exterior image; doesn’t have a united vision (because the human life and the world are unstable, unfinished and indeterminate); doesn’t want to draw reader’s opinion but on the contrary he is left to provide hi own interpretation.