Thanks, Branny, your explanation helps a lot. Man-- This building is just...wrong; it looks as though a normal building has developed a horrible cancerous growth. I noticed it was labeled "Modernism and Postmodernism overlap".
But The Hearst Tower in Manhattan is stunningly beautiful.

The first site gives this, which I found interesting: Postmodernism is hard to define. Many opinions differ about whether it is a period, a set of styles, or a broader set of politics and ideologies. The term has described fashions throughout the years as well as media driven political campaigns in the 1990s. Modernism seems easier to pinpoint. The term "modern" means present or contemporary. In the art world the term expresses the self-consciousness of something that relates itself to the past. Increased technology advances and urban development helped modernity. Modernism and Postmodernism overlap. There is no precise moment of transition between the two. Postmodern art often does parodies or reproductions while Postmodern architecture steps out of the box to think of eye catching designs that may not even serve as functional.