Wordless picture books, according to Arizona State University professor Frank Serafini, have "visually rendered narratives".
The reader must interpret the character's actions, feelings, and motivations without text to affirm; understand some ambiguity in the narrative may remain; and create and explain hypothesis about the events of the book.
[1] Further, some wordless picture books address themes like slavery which are topically more appropriate for older readers.
[1][3] This kind of work can also be useful with English-language learners as it lets them improve their spoken language proficiency with texts more complex than they would be able to read in English.
[3][4] Wordless picture books can also be used as writing prompts, with students providing their own narration or dialogue.