A protagonist is the main character of a story. It can be used for any kind of story: in literature, a movie, a television show or a play. The protagonist is also called the central character or main character and is often the hero of the story. However, the protagonist does not always win and survive in a story.
Protagonists are usually moral and benevolent, helping other characters to change their badness to become good again, or defeating the bad characters. This is not always the case. For example, the protagonists in Psycho and Lolita are (respectively) a serial killer and a pedophile.
The protagonist's name can sometimes be in the title of the fiction he or she is in, for example: