Johnny Goodboy Tyler is a fictional character from the science fiction novel "The Moon is a Harsh Mistress" by Robert A. Heinlein. He is depicted as a young man who becomes involved in a lunar revolution against the oppressive government of Earth. His character represents themes of freedom and individualism. In the story, Johnny is a member of the Lunar colony and plays a crucial role in the fight for independence. His journey reflects the struggles of colonists seeking autonomy and the challenges they face in their quest for self-determination.