Authors use characterization to introduce and describe their characters for their readers. Characterization includes anything that makes the character come alive as a real person, especially if the character is a dynamic character, like the protagonist of a story. Aspects of characterization include a character's thoughts, actions, emotions, personality, and what the character looks like.
Authors can also describe characters through either direct or indirect characterization. When using direct characterization, an author uses descriptive sentences to tell the reader what the character is like. In contrast, when using indirect characterization, an author uses the character's actions, thoughts, and conversations with other characters to show the reader what the character is like. In her short story "Floating Bridge," author Alice Munro uses primarily indirect characterization to describe Jinny as a very insecure character who is battling against life's hardships.
In the very beginning of the story, we learn that Jinny feels angry towards her husband Neal and wants to isolate herself from him. She isolates herself from him temporarily by spending a day in a bus shelter near her home, reading the graffiti on the walls. By the time she is ready to leave the shelter and return home, she has realized that, during her isolation, she may have been the only one to think her feelings have any importance, nobody else. She reflects upon the fact that she has never been the sort of person many people care about, or as she phrases it, "She was not, after all, somebody people flocked to in the world."
As we progress through the story, we learn that her feelings of isolation are partially due to the fact that she has terminal cancer. Her cancer has driven a wedge between herself and her husband because her cancer makes her feel sexually undesirable. Hence, her cancer, feelings of isolation, feelings of being unwanted, and the anger she feels towards her husband are all part of her characterization, and these aspects of her characterization help move the story forward and bring the story to its resolution.