Conversational
As a graphic novel, most of the language is dialogue, with the images doing the work of setting the scene and representing the action. Thus the writing style tends to be conversational, closely following the speech patterns of Art and Vladek, including Vladek’s imperfect English. Tone and emphasis are conveyed through letters that are either enlarged, italicized, or in bold.
For a discussion of some of the images in Maus, see "Symbolism, Imagery, Allegory."