As some of you may know, I studied screenwriting before I decided to jump into books. The name Syd Field was the first name I learned while attending the New York Film Academy in L.A.
Among other books, Syd Field was the author of Screenplay: the foundations of screenwriting and The Screen Writer's Workbook. These books break down the three-act structure to the very basics of storytelling. Unfortunately, Mr. Fields recently past away. He left behind a legacy of screenwriters--including James Cameron and Judd Apatow--who benefited from his teachings.
The three-act paradigm above was Syd Field's baby. It's an amazing tool that can help you plot out your story.
Though I haven't touched a screenplay since I started the Sapphire series, I still use the same structure for my books. To me, the three-act structure, and all it includes, isn't only for film and plays. It is the very essence of how a story should naturally unfold. There is a reason the three-act structure has stuck around since it originated in ancient Greece with Aristotle; it works.
A novel might run to be around 300 pages while a screenplay only runs to be 110 pages. Because of this, you can't use the exact page count structure for novels that is used in screenwriting, but the acts are still the same, and the way the story should unfold still holds true.
RIP, Mr. Field, and thanks for enlightening us.