What is postmodernism?

Postmodernism is a practice. My teacher suggested me what if after postmodernism, post-postmodernism? After that again? He says that there is no answer. He continues that it is the most ambiguous word that has been chosen.

One day while I was coming from Tapoban, Nagarjun, on the way to Balaju, one car struck a village woman carrying green vegetable on her back in a bamboo basket. The car owner said that he wanted to purchase a bundle of green leaves that had been carried by the woman.

Why did the woman come to the town? What made her earn money by selling green vegetables? Why did the car owner, the city man need village product? If not so and so it wouldn't be.

This is postmodernism.