As you are developing your cast of characters for your novel, you will undoubtedly finding most of your characters falling into one of two categories – major character or minor character.
Major characters include your protagonist, your protagonist’s sidekick and your antagonist (and perhaps his sidekick/major underling).
These are the people that clearly make the major character list and are the characters you will need to develop fully. You will need to know beyond their physical characteristics and personality traits and flaws. You will need to know their history and what happened to make them the way they are at the beginning of your story.
But other people may help out your protagonist or antagonist. They even may have their own subplots. These also are considered major characters. They are going to affect the story. But this list usually is a short one.
So for the Harry Potter series – Harry (protagonist), Ron and Hermione (sidekicks) and Voldermort (antagonist) are definitely major characters. Others include Headmaster/Professor Dumbledore, Professor Snape and Draco Malfoy to name a few. And with this example, there are some characters who might have been minor in the first books who play bigger roles later.
Minor characters are the opposite of major characters. Very little is usually written about them. They may appear in a scene or two but aren’t likely to influence the outcome of the story.
Many of these characters are flat, two-dimensional types that could easily be replaced. As an author, you are not going to spend the time to flesh these people out before writing.
Heck, some of these minor characters may not even have names. The bartender or cab driver may be such a character. They may speak and interact in the scene, but their contribution is negligible.
In the Harry Potter series, minor characters include the Dursleys, Filch, and many of the other professors and students.
And in your own novel, there will be many characters who may fall in between but don’t waste your time trying to categorize each one. Simply decide how important they are to the story, and that will let you know how much time to spend on them. To read more about how much to develop minor characters – check out my post on that subject.