A list of postmodern characteristics.

Irony, playfulness, black humor
Postmodern authors were certainly not the first to use irony and humor in their writing, but for many postmodern authors, these became the hallmarks of their style. Postmodern authors will often treat very serious subjects—World War II, the Cold War, conspiracy theories—from a position of distance and disconnect, and will choose to depict their histories ironically and humorously.

http://books.google.com/books?id=Xfze51E7TEoC&printsec=frontcover&dq=catch-22&ei=HNsISpu3M5f2MIzRwYYE

Pastiche
Many postmodern authors combined, or “pasted” elements of previous genres and styles of literature to create a new narrative voice, or to comment on the writing of their contemporaries. Thomas Pynchon, one of the most important postmodern authors, uses elements from detective fiction, science fiction, and war fiction, songs, pop culture references, and well-known, obscure, and fictional history.

http://booksoupbookstore.blogspot.com/2008/05/unfortunates-by-bs-johnson.html

Intertextuality

An important element of postmodernism is its acknowledgment of previous literary works. The intertextuality of certain works of postmodern fiction, the dependence on literature that has been created earlier, attempts to comment on the situation in which both literature and society found themselves in the  second half of the 20th century: living, working, and creating on the backs of those that had come before.

http://books.google.com/books?id=RC6JJmB_JEcC&printsec=frontcover&dq=rosencrantz+and+guildenstern+are+dead&ei=q9sISoqMMYjYMOqLrNAD

Metafiction
Many postmodern authors feature metafiction in their writing, which, essentially, is writing about writing, an attempt to make the reader aware of its ficitionality, and, sometimes, the presence of the author. Authors sometimes use this technique to allow for flagrant shifts in narrative, impossible jumps in time, or to maintain emotional distance as a narrator.

http://books.google.com/books?id=FM4y7N1kM9AC&printsec=frontcover&dq=slaughterhouse-five&ei=JdwISu7zLZasM4n7jIsG

Historiographic metafiction
This term was created by Linda Hutcheon to refer to novels that fictionalize actual historical events and characters: Thomas Pynchon’s Mason and Dixon, for example, features a scene in which George Washington smokes pot.

http://www.amazon.com/General-Labyrinth-Gabriel-Garc%C3%ADa-M%C3%A1rquez/dp/0140148590

Temporal distortion
Temporal distortion is a literary technique that uses a nonlinear timeline; the author may jump forwards or backwards in time, or there may be cultural and historical references that do not fit: Abraham Lincoln uses a telephone in Ishmael Reed’s Flight to Canada. This technique is frequently used in literature, but it has become even more common in films.

http://books.google.com/books?id=4269Rt0vqTIC&printsec=frontcover&dq=flight+to+canada&lr=&num=50&as_brr=3&as_pt=ALLTYPES&ei=s9wISsguk841mYeBow4

Paranoia
Many postmodern authors write under the assumption that modern society cannot be explained or understood. From that point of view, any apparent connections or controlling influences on the chaos of society would be very frightening, and this lends a sense of paranoia to many postmodern works.

http://books.google.com/books?id=vp2Sv9KO1VUC&printsec=frontcover&dq=crying+of+lot+49&lr=&num=50&as_brr=3&as_pt=ALLTYPES&ei=BN0ISsjXMIvKNdv-tYUC

Maximalism
Villified by its critics for being in turns disorganized, sprawling, overly long, and emotionally disconnected, maximalism exists in the tradition of long works like The Odyssey. Authors that use this technique will sometimes defend their work as being as long as it needs to be, depending on the subject material that is covered.

http://books.google.com/books?id=xbeUMn6pi2UC&printsec=frontcover&dq=howl&lr=&num=50&as_brr=3&as_pt=ALLTYPES&ei=IN0IStmwNYvKNdv-tYUC

Faction
Faction is very similar to historiographic metafiction, in that its subject material is based on actual events, but writers of faction tend to blur the line between fact and fiction to the degree that it is almost impossible to know the difference between the two, as opposed to metafiction, which often draws attention to the fact that it is not true.

http://books.google.com/books?id=mYC3yRvvXxMC&printsec=frontcover&dq=in+cold+blood&lr=&num=50&as_brr=3&as_pt=ALLTYPES&ei=et0ISonVK4a6NarmnKcB

Magical realism
Arguably the most important postmodern technique, magical realism is the introduction of fantastic or impossible elements into a narrative that is otherwise normal. Magical realist novels may include dreams taking place during normal life, the return of previously deceased characters, extremely complicated plots, wild shifts in time, and myths and fairy tales becoming part of the narrative. Many critics argue that magical realism has its roots in the work of Jorge Luis Borges and Gabriel García Márquez, two South American writers, and some have classified it as a Latin American style.

http://books.google.com/books?id=Jumamrx5UgoC&printsec=frontcover&dq=labyrinths&lr=&num=50&as_brr=3&as_pt=ALLTYPES&ei=i90ISsCNIoOgNfGsqOwD

http://books.google.com/books?id=W6oIvSR4MQkC&printsec=frontcover&dq=100+years+of+solitude&lr=&num=50&as_brr=3&as_pt=ALLTYPES&ei=p90ISvfjPI3MM7a1uO0B

Participation
Many postmodern authors, as a response to modernism, which frequently set its authors apart from their readers, attempt to involve the reader as much as possible over the course of a novel. This can take the form of asking the reader questions, including unwritten narratives that must be constructed by the reader, or allowing the reader to make decisions regarding the course of the narrative.

http://en.wikipedia.org/wiki/Choose_Your_Own_Adventure