What is Postmodernism?

Postmodernism is a late 20th century movement that consists of interpretations of art and culture. In the book "Postmodernism For Beginners", it is shown that the post-modern era was based on the advancement of science but it is was also a movement where artists were able to portray what life was like after bad periods like the war and what other people have mentioned about it. Postmodernism is mainly a reaction to how certain people see reality and according to the book, "it is a reaction to the most profound spiritual and philosophical crises of our time which is the failure of the Enlightenment, which was the era of reason where views on art and society were changed and the capacity to think for ourselves was to be important.