Well, the structure of a short story is typically concise. It doesn't have much room for digressions. It focuses on one main idea or event. The paragraphs are usually short and the whole story moves forward at a brisk pace. A novella, however, can afford to have a more complex structure. It might start with a prologue that sets the scene in a broader context. Then it has a main body with different parts that develop the story gradually. It can also have an epilogue. For instance, some novellas use flashbacks and flash - forwards within their structure, which is less common in short stories as short stories are more about immediate storytelling.
A short story's structure is quite simple. It's like a mini - journey. You start at a point, move through a small conflict or situation, and reach an end, all in a short span. There's not much space for a complex build - up of events. In contrast, a novella has a more developed structure. It can have a slow - burning start where the author takes time to introduce characters, settings, and the overall mood. It can then gradually build up the plot with various sub - plots emerging. And the ending of a novella can be more drawn - out and reflective compared to the quick and often conclusive ending of a short story.