In literature, the setting is the time, place, physical details, and circumstances (like weather) in which a situation occurs. The setting may also include the background or environment where the characters live and the action takes place. It usually means physical surroundings. The setting is important because it can help the reader envision the story and is very important to the mood of a story. Think about a setting in which it is a dark and stormy night. The characters are in an old house and the power has just gone out . This setting establishes the “feeling” that something scary is about to happen.
Easy: the background, the place, the area...where the story takes place is the setting.
Think space for Star Wars
Think Hogwarts for Harry, Ron, etc.
Think America for many of Twain's works
Hope that helps!
The setting is something that is common to every story. It describes when and where a story takes place.