Readers usually take for granted what they know and are able to predict about characters, settings, events, story shapes, etc. in works of fiction. We frequently say when criticizing a fictional work that a movie, novel, or short story is too "predictable." What we imply by this sort of statement is that we recognize, for example, a certain plot device or character type in the story or movie with which we are familiar. That familiarity allows us to create expectations or predictions about what happens next in the story or how a character will act. If a story or movie follows our predictions, it gives us a diminished degree of pleasure, because it seems unoriginal and formulaic. The short-short genre, however, thrives on taking that same familiar (and sometimes formulaic) material and exploiting it to create effective fictions. The reader's sense of the familiar becomes an integral component in the art of composition.
Applying Hemingway's theory of omission, we can say that, if a reader will find a situation, character, conflict, etc. in a short-short familiar, then the writer can leave out a very large amount of information about that situation, character, or conflict. Charles Baxter says, "In the abruptly short-short story, familiar material takes the place of detail. Oh yes, the reader says: a couple quarreling in a sidewalk restaurant, a nine-year old boy stealing a Scripto in Woolworth's, a woman crying in the bathtub. We've seen that before. We know where we are." (Sudden Fiction 229) There are situations and characters that we encounter so commonly in both everyday life and in fiction that they are immediately recognizable. With even the most briefly described situation, we infer back story, envision settings and character traits, and predict future events.
To use one of Baxter's examples, if a fiction mentions "a couple quarreling in a sidewalk restaurant," we quickly assume a number of things. First, we assume the couple is a man and a woman. We also infer that they're in a romantic relationship and that their argument relates to that relationship. When the man raises his voice, we could very easily imagine the curious glances of people passing by the sidewalk restaurant. Where is the sidewalk restaurant? We'd picture a large, bustling city like Paris or New York. Because our imaginations tend to run wild when we read, a large amount of information can be implied by a small amount of text.
In Elizabeth Tallent's "No One's a Mystery," for instance, the reader can imply that the narrator and Jack are having a romantic affair from the first few lines of text without the fact ever being implicitly stated.

For my eighteenth birthday Jack gave me a five-year diary with a latch and a little key, light as a dime. I was sitting beside him scratching at the lock, which didn't seem to want to work, when he thought he saw his wife's Cadillac in the distance, coming toward us. He pushed me down onto the dirty floor of the pickup and kept one hand on my head…

The diary Jack gives the narrator, his wife's approach on the road, and his reaction to his wife's approach suggest a wealth of knowledge about the characters and the situation into which Tallent places them. Jack's marriage implies that he is much older than the 18 year-old narrator. His reaction when he sees his wife implies that he's concerned about being caught with the narrator and suggests that they are doing something that they wouldn't want his wife catching them doing--having an affair. As readers, we do most of this fairly pedestrian interpretation automatically. Experienced readers go even further and start wondering what Jack holding the narrator's head to the floor (and her allowing him to do so) says about the power dynamic or degree of respect in the relationship. Through repeated close reading, we continually find new richness and suggestion in Tallent's language, right down to seemingly trivial details, the vehicles Jack and his wife respectively drive, for example. Only after the tenth time looking over "No One's a Mystery," did this reader notice that Jack drives a dirty pickup and his wife drives a Cadillac. This detail could imply a considerable disparity of wealth between the characters or that the two inhabit live somewhat different lifestyles.