Most stories present at least one main character, called the protagonist.
Originally, the protagonist was the actor who played the leading part in a Greek drama. The protagonist may or may not be a hero but is always the character most central to the action. In a story told from the first-person point of view, the narrator may or may not be the protagonist. In the stories of Arthur Conan Doyle, for example, Dr. Watson, the narrator, tells the exploits of Sherlock Holmes, the protagonist. In David Copperfield, however, David is both narrator and protagonist.