This is a great site to start at if you're looking to learn more about postmodernism. The site provides useful definitions of postmodernism from trusted and well nown dictionaries, including Merriam-Webster. The site also explains several ways in which the term is used within literature, drama, architecture, etc. There is a lengthy and highly informative section on the history of the term postmodernism as it was first used and continues to be used. Although many use the words postmodernity and postmodernism interchangeably this site clearly explains the difference between the two. There are also sections devoted to postmodern architecture, postmodern music, and notable philosophical and literary contributors; as well as deconstruction, social construction, and criticisms of postmodernism.