Below, we will discuss storytelling, especially as it relates to film.
Narrative: a story
Narration: the art of telling a story
Narrator: who or what tells the story
In narrative film, narration and the narrator can be drastically different than what we are used to from other forms of narrative fiction.
In film, sometimes the narrator is the camera itself-- think of it like a 3rd-person omniscient narrator from fiction, except the camera must occupy a specific position in the scene. The camera is also unlike a 3rd-person omniscient narrator in that the camera does not have access to interiority-- that's why we need actors who can emote and express feelings. Other times, we get the camera as a 1st-person narrator, this happens in a point-of-view shot, or in times of shot-reverse shot. We can even get narration from the characters themselves in the form of voice-over narration.
All narrative films feature characters working toward goals. The main character of the story is known as the protagonist, and his main adversary is known as the antagonist. It must be noted that "protagonist" is not a synonym for "hero," as we can see that the protagonist of Scarface is not heroic or morally good in any way. It must also be noted that the antagonist does not always need to be another character-- it can be something as abstract as "nature" or even (again, as in the case of Scarface) the protagonist himself.
Characters are typically broken into two categories: round and flat. Round characters are characters who grow or change over the course of the narrative; flat characters are characters who stay about the same throughout the narrative. Do not confuse round and flat with complex and simple, though! At times, round characters can be remarkably simple: take the generic hero story of characters like Harry Potter, Luke Skywalker, or Bilbo Baggins. They grow and change throughout their narratives, but do so according to conventional narrative tropes. Similarly, flat characters are not always simple, but find complexity in their singular motivation throughout the film.
in medias res is a Latin term meaning "in the middle of things." Narratives, in their attempt to simulate the world, are forced to begin with a character in the middle of his life, already a formed individual with goals and desires. The story truly begins when those previous drives are replaced with the new motivation that will shape our story.
Next, our character needs to encounter some obstacles on his journey to his goal. These typically come from the antagonist, although some stories feature multiple obstacles from multiple antagonists.
As the character encounters (and possible overcomes some of) these obstacles, the stakes begin to rise. His proximity to his goal fluctuates-- he gets closer or farther-- in order to raise or lower the stakes. The process of increasing stakes is known as the rising action, which puts us on an upward trajectory to the film's conclusion.
Finally, in the climax, our main character must confront his most extreme obstacle in order to capture his desire. The moments after he realizes his dreams are known as the resolution or "falling action" as the character readjusts to a new world following his adventure.
Story vs. Plot
Story and plot are actually two different concepts that frequently overlap. In order to understand the difference, we need to understand diagesis.
Diagesis refers the way our characters experience their world. Everything they can see, hear, touch, smell, or otherwise interact with is part of the diagesis. These elements are called "diagetic" elements. A portion of film exists outside of the diagesis, however. These "non-diagetic" elements are things that we can see or hear but our characters cannot. Think of things like the soundtrack or title screen cards as examples of non-diagetic elements.
Below, you'll see a humorous commercial that finds its gag in toying with our expectations of diagesis. We expect that the title card is non-diagetic. The joke is that it isn't, and the cowboy hits his head.
Story is the entire world that surrounds the events of the narrative. All of the diagetic material of the story-- the things our characters experience in the world-- is part of the story, as well as many implied events that take place off camera (we do not need to see our characters get 8 hours of sleep, for example).
Plot is the specific elements presented to us on screen. This includes the diagetic material the director presents us with, as well as all non-diagetic material we see and hear as well. Our main characters cannot hear the soundtrack, but we can.