Every symbol (in life and in literature) is composed of two parts: the symbol (the actual picture, such as a skull and crossbones) and a referent (the thing for which the symbol stands, such as poison). Writers use symbols as a matter of course: things like the river in The Adventures of Huckleberry Finn or Hester's "A" in The Scarlet Letter allow readers to better grasp the meanings of each work as a whole.

However, part of what makes "A Perfect Day for Bananafish" so intriguing is Salinger's use of symbols where the referents are highly ambiguous. The most notable example of this is the story of the bananafish itself. Seymour says that these imaginary fish lead "very tragic" lives, since they are "very ordinary-looking fish" until they swim into the banana hole, where they eat so many bananas that they get banana fever (a "terrible disease") and...