Not all characters in your story are created equal. Some are of the utmost importance while some are fairly insignificant.

The most important characters are the ones who face and overcome a number of serious problems and obstacles in a story. They are called major characters. In Antoine de Saint-Expiry’s “The Little Prince,” they would be the Little Prince and the boy narrator. In “The Godfather” (both novel and movie), they would be Don Vito Corleone and his sons Michael and Sonny.

In contrast, minor characters face few obstacles and often none at all. Because of this, minor characters have few lines of dialogue and usually appear only incidentally. They are part of the background, necessary for advancing the plot and giving the story a semblance of reality, but they are not who the story is about. In “The Little Prince,” they would be the fennec fox, railway switchman, and the merchant. In “The Godfather,” they would be the singer Johnny Fontana, the henchman Luca Bras, and Connie’s husband Carlo Rizzio.

Developing all of your story’s characters isn’t necessary. In fact, the fewer you develop the better, especially if writing a short story or novella. This allows the reader to focus on a single character (or small band of characters) who must overcome the story’s central problem.

At the same time, don’t skimp on minor characters if they’re needed in your story. The tale about the scientist professor making a startling but dangerous discovery probably needs to include a research assistant, department secretary, and bored students. There’s nothing wrong with including these side players. Just make sure they seem real (that is, they shouldn’t be stereotypes) and that they don’t attract the reader’s attention too much.