Filler words also play a role in the development of the narrative voice. An omniscient narrator might use different filler words compared to a first - person narrator. The choice of filler words can also change over the course of the novel as the character grows or the situation changes. For instance, a character who becomes more confident might use fewer filler words as the story progresses.
In novels, filler words can also be used for character differentiation. A nervous character might use more 'um's and 'ah's compared to a confident one. They can be a subtle tool for characterization. Moreover, in some cases, filler words can be used to create a regional or social dialect. For example, certain words might be more common in a rural setting's dialogue, which can help to paint a more vivid picture of the world in the novel.