Prose is essentially just writing. It isn't in a poetic form. A short story or novel is in the form of prose. On the other hand, poetry has a set form most of the time. It often has a rhyme scheme and uses many methods to emphasize the topic without saying what it's actually about. Poetry is often harder to interpret. Generally, both use metaphor, simile, and figurative language to make the reader think about the author's meaning, but poetry also uses the rhyme scheme and format to get the meaning across. Poetry is also often more controversial and difficult.