* Prequel: This is the most common and general term for a story that takes place before the original. It's used for stories that are directly related to the original, often exploring the backstory of characters or events.
* Origin story: This term is used specifically for movies that focus on the origin of a character or event. For example, the origin story of Batman is a prequel to the Batman movies.
* Backstory: This term is less common, but can be used to describe a movie that focuses on events that happened before the original, even if they are not directly related to the main plot.
It's important to note that these terms are not always used consistently, and sometimes a movie might be considered both a prequel and an origin story. Ultimately, the most accurate way to describe a movie that takes place before the original is to simply say that it is a "prequel" or "a story that takes place before the original."