The protagonist is the central figure of a story, and is often referred to as a story's main character.

The story follows and is chiefly concerned with the protagonist (or, sometimes, a small group of protagonists—see usage below). Often the story is told from the protagonist's point of view; even when not in first-person narrative, the protagonist's attitudes and actions are made clear to the reader or listener to a larger extent than for any other character.

The protagonist is also characterized by his ability to change or evolve. Although a novel may center around the actions of another character, as in Herman Melville's "Bartleby the Scrivener", it is the dynamic character that typically allows the novel to progress in a manner that is conducive to the thesis of the work and earns the respect or attention of the audience.

The protagonist is, it should be pointed out, not always the hero of the story. Many authors have chosen to unfold a story from the point of view of a character who, while not central to the action of the story, is in a position to comment upon it. However, it is most common for the story to be "about" the protagonist; even if the protagonist's actions are not heroic, they are nonetheless usually vital to the progress of the story. Neither should the protagonist be confused with the narrator; they may be the same, but even a first-person narrator need not be the protagonist.

The protagonist is often faced with a "foil"; that is, a character known as the antagonist who most represents or creates obstacles that the protagonist must overcome. As with protagonists, there may be more than one antagonist in a story.