Postcolonialism

It is a specifically post-modern intellectual discourse that holds together a set of theories found among the texts and sub-texts of philosophy, film, political science, human geography and literature. These theories are reactions to the cultural legacy of colonialism.

Marxism

It is the economical and political philosophies of Karl Marx and Friedrich Engels that hold that human actions and institutions are economically determined and that class struggle is needed to create historical change and that capitalism will ultimately be superseded by communism.

Psychoanalytic Criticism

It is a form of literary criticism which uses some of the techniques of psychoanalysis in the interpretation of literature.

Sigmund Freud's ideas:
All of freud's work depends upon the notion of the unconscious, he was not the discover of the unconscious, his uniqueness lies in his attributing to it such a decisive role in our lives.
"For Freud, the unresolved conflicts that give rise to any neurosis are the stuff of literature. A work of literature, he believes, is the external expression of the author’s unconscious mind. Accordingly, the literary work must be treated like a dream"

Post-structuralism

Post-structuralism encompasses the intellectual developments of certain continental philosophers and sociologists who wrote within the tendencies of twentieth-century French philosophy. The movement is difficult to define or summarize, but may be broadly understood as a body of distinct responses to structuralism (hence the prefix "post").
Many contributors, most notably Jacques Derrida, Michel Foucault, and Julia Kristeva, either inverted structuralist principles or set out to reject them outright.
In direct contrast to the structuralist claim of an independent signifier superior to the signified, post-structuralism generally views the signifier and signified as inseparable but not united; meaning itself inheres to the play of difference.