When writing a story we must provide enough background information for the reader to get their bearings. If not they get lost in what is going on and can’t understand the story. The worst way to do this is to have the narrator fill the reader in through paragraphs of exposition, called an information dump. This, unfortunately, many of us have slogged through before. It isn’t pleasant. Readers and editors will often stop reading if it feels like a history text book.
There are several good ways to provide background information to the reader without bogging down the story in exposition. One I really like is the noob.
The noob is the character who is new to the situation, like the reader. The more seasoned characters have to tell them what it going on. The trap to avoid is having the experienced character info dump to the noob. The noob is like a baby, they must be spoon fed little by little, because their stomachs are so small. Giving just enough information to get through the current scene.
The Noob can be the main character. This is often done in a “Hero’s journey” type of story. Look Star Wars. In the first movie, A New Hope, Luke knows nothing of the Jedi Knights and not much about the rebellion. First Obi-Wan teaches him and we, the viewer, learn along with him. He also learns from Han and Leia.
The Noob can be a secondary character. In the more recent movie, Fantastic beasts and Where to Find Them, Kowalski is the Noob who gives Newt the chance to explain things to.
So go out and develop your inner Noob