The Hero’s Journey is a pattern of narrative identified by the American scholar Joseph Campbell that appears in drama, storytelling, myth, religious ritual, and psychological development.  It describes the typical adventure of the archetype known as The Hero, the person who goes out and achieves great deeds on behalf of the group, tribe, or civilization. 

We think all Filmmakers should know about The Hero's Journey! 

Glove and Boots explains it very nicely...with puppets.