How does post modernism relate to post structuralism?

Question

Going through the wikis of both, I get a similar feeling from both of them, but I can't put in words exactly how they are related. Here are simple introductions from wiki:

Postmodernism is an intellectual stance or mode of discourse characterized by skepticism toward the "grand narratives" of modernism; rejection of epistemic certainty or the stability of meaning; and sensitivity to the role of ideology in maintaining political power. Claims to objectivity are dismissed as naïve realism, with attention drawn to the conditional nature of knowledge claims within particular historical, political, and cultural discourses. The postmodern outlook is characterized by self-referentiality, epistemological relativism, moral relativism, pluralism, irony, irreverence, and eclecticism; it rejects the "universal validity" of binary oppositions, stable identity, hierarchy, and categorization.

Vs, post structuralism,

Structuralism proposes that human culture can be understood by means of a structure that is modeled on language. As a result, there is concrete reality on the one hand, abstract ideas about reality on the other hand, and a "third order" that mediates between the two.

A post-structuralist critique, then, might suggest that in order to build meaning out of such an interpretation, one must (falsely) assume that the definitions of these signs are both valid and fixed, and that the author employing structuralist theory is somehow above and apart from these structures they are describing so as to be able to wholly appreciate them. The rigidity and tendency to categorize intimations of universal truths found in structuralist thinking is a common target of post-structuralist thought, while also building upon structuralist conceptions of reality mediated by the interrelationship between signs.

Answer 1

Postmodernism and poststructuralism have a great deal in common. As far as major themes are concerned, there is a lot of overlap. Both of them deal with questions of language, meaning and history. They also reject classical systems of metaphysics (of Platonic / Hegelian type).

The subject is infinitely deep and complex, so I will just address 2 particular thinkers from each intellectual movement in my answer.

There is no 100% satisfying definition of what exactly postmodernism is, or even which thinkers can be classified as postmodern (for example, is Nietzsche postmodern, and what about Heidegger?). However, the greatest postmodern philosopher ever was Jacques Derrida.

Derrida's difficult writings mostly deal with metaphysics and language. He dismantles metaphysical systems using the infamous linguistic technique of deconstruction. Language betrays weak points of metaphysical constructs. For example, Derrida concluded that there is no metaphysical presence. That which the Western European metaphysics claimed to be "given", "present" and "immediate" for 2000 years is actually a clever cover up job, and this trick succeeded for so long because of linguistic manipulation. It took the genius of Derrida to uncover it.

The greatest poststructuralist thinker was another Jacques, but this time Lacan. He completed Freud's project using linguistics. Lacan's thought was similar to Derrida's in many ways (although they had some major disagreements), and he also deconstructed (if that term can be applied to Lacan) many major metaphysical concepts using modern linguistics and psychoanalysis. For example, he rejected the notion that there is such a thing as a clear and distinct subject in the Cartesian sense.

To recap the main thought: language and linguistic analysis provide us with tools that can help us dismantle wrong metaphysical / psychological theories. This is precisely where postmodernism and poststructuralism agree 100%.