How are the theory and art of the short story defined?

The fictional form of short story was defined by Edgar Allan Poe, who felt people were sometimes too distracted by "worldly interests" to read novels. Poe thought a shorter form of narrative concentrated upon a single, powerful impression would hold the reader's interest, and, in fact, be the best type of fiction.

Of course, the short story shares with other forms of fiction the basic elements of plot, characterization, point of view, setting, symbols, theme, and tone. But because the short story is so concentrated, its settings are restricted, there are a limited number of characters, its plot has a narrow range of action, and there are usually only one or two themes. Sometimes an author places emphasis upon just one of these fictional elements. For instance, Poe often focused his tales upon an unreliable narrator/character. This skewered point of view frequently affects other story elements such as the story's tone, plot, and character development. Thus, in Poe's writings (and in those of other authors, as well, who may focus on another particular element), the short story is further distinguished from longer forms of fictions by its unity of the essential story elements. If the short story is executed successfully, these occur at once in the tale, creating the powerful impression desired. This effect, along with its brevity, have come to make the short story a very popular literary form.