The bottom line represents non-diegetic time, usually around 2 hours. This 2 hours is divided into usually 3 acts.
An angled line rises from the left, and some fool called it "Rising Action." That's fine if the action is always rising, but it's not always rising. So my line is crooked. It's filled with PLOT BUMPS which represent those events in a film to which characters need time to react. It happens every 6-8 minutes or so, by my guess. Remember Hakuna-Matata? Definitely not rising action -- more of a chilling out, leveling out.
All of this does culminate in the CLIMAX of the film, the point of highest action which will lead to our conclusion and resolution. And that final line angling down to the end of the movie? Certainly NOT "falling action." We'll call it DENOUEMENT. Say it like you're French. It's that resolution that puts a big fat bow on the gift of the movie. It's Luke and Han and friends receiving medals for saving the Universe (for now!). It's Simba taking the throne and making a cub (sing with me now... "The Circle of Life.") It's the visual answer to the ESSENTIAL QUESTION.
The ESSENTIAL QUESTION is asked at the beginning of the film and related directly to the goals of the protagonist. In Little Shop of Horrors, it's about Seymore wanting to not be poor. In Independence Day, it's about our protagonist getting engaged to his girlfriend. Note that in neither movie is it about defeating aliens.
The early part of the movie (in the 1st act) is called EXPOSITION. It's basically all the background stuff we need for the plot to launch. We get the ESSENTIAL QUESTION, and we also get some character development from our main characters to find out what makes them tick and to make their reactions to later situations somewhat predictable (in a good way). Of course, the most important thing we are exposed to in EXPOSITION is the SETTING, which is the time and place (A Long Time Ago, in a Galaxy Far Far Away...).
Here's a bonus for you students who actually read this stuff. There is an old theater idea of a GREEK CHORUS. It was a group of 3 women who would stand at the side of the stage and direct the audience in how to feel. They, like us, are observers of the action and only minimally participate in the action, if at all. Remember the mice from Babe? Greek chorus. Or the annoying radio announcer from The Fifth Element? Or Mr. Senor Love Daddy from Do the Right Thing? Or the doo-wop girls from Little Shop of Horrors? Or the very literal Greek Chorus from Hercules? There you have it; all Greek Chorus. Some would convincingly argue that a movie's non-diegetic music is a modern Greek Chorus. When Batman comes crashing through a window, the music tells us "This is really big and scary!"