When writing a story, there are nearly countless different types of characters you can use to fill out the cast. There's the hero, the anti-hero, the villain, the love interest, the best friend, the redeemed, and many, many others. For the purposes of this tutorial, we will focus on three primary character types; the protagonist or main character, the antagonist or main villain, and the supporting characters.

Protagonist - Obviously yours story needs a central character to focus on. You could in theory write a book about the life of an inanimate rock, but that's not going to be very interesting. The protagonist is the character around whom yours story revolves. He or she should have a kickoff point for their character, introducing them in such a way that your audience comes to sympathize with them and truly care about what becomes of them over the course of yours story. Then, over the course of the story the character will develop as the plot puts them in challenging situations and they are forced to rise to meet them. Whether the character becomes a better person for it or ultimately meets with a tragic downfall is up to you, but it is important that they do develop. Naturally, they need a catalyst to facilitate that development, which brings us to our next point...

Antagonist - The antagonist is the force that is acting against your protagonist. The reasons why this is may vary. Perhaps the antagonist is an evil dictator and your hero is the One True Heir out to reclaim their throne. Maybe the villain is an assassin who killed your protagonist's family, and the hero is on a journey seeking revenge. Maybe the antagonist is just a schoolyard bully who gets his jollies from pushing your character into the mud. Whatever the case, it is important to establish a visible antagonist early on in the story so that your hero has a reason to make their journey through the plot. It doesn't have to be the main antagonist that you introduce initially; revealing an even bigger enemy than the reader previously knew about is a common and well-established plot twist. It's just important that you have some sort of antagonist almost from the beginning. (Take note that the antagonist is a force that operates against your protagonist. It's usually a character, but it doesn't have to be. Your character could be lost in the woods, and the force he's working against is nature itself, not any individual person or group.)

Secondary Character - You have your hero and your villain, but it's hard to set up a story with just those two characters. Secondary characters populate your world and help move the story along. There are two main subclasses of secondary characters; supporting characters and minor characters. Minor characters exist primarily for the purpose of making the story more interesting and relatable because a world without people seems flat and hollow. The story could still be told without them, it would just be harder. By contrast, supporting characters are essential to the plot. They play a direct role in the plot and have a heavy impact on the storyline.