Theater is the physical location where an event or a scene unfolds. It’s the container, the box. Each scene can have a different scenario and may even mutate or evolve over the course of the story. There may be many different scenarios in the same setting. If we were to take a photograph of the characters, it would be the section in the background. It’s usually restricted and limited to the immediate vicinity of the characters. A static scenario serves as an introduction and then a few new references can be made. On the contrary, it becomes a resource to demonstrate that characters are in motion, describing the interaction with elements of a changing scenario.
The scenario is where you should follow the phrase of “show, don’t tell”. This means to expose the reader to a scene that engages the senses by means of the letters. You are transporting them to a specific time and inserting them right in the middle of that place. It’s about creating a three-dimensional site instead of just giving a summary of what is visible.