The term 'Character Journey' is a concept used in storytelling, where the protagonist of a story undergoes a transformation or journey throughout the narrative. The three-letter acronym ARC stands for 'Affective, Relational, and Cognitive, ' which are the three stages of a character's journey. Affective refers to the emotional changes the character experiences, Relational is the relationships the character has with other characters, and Cognitive is the character's growth in understanding and knowledge.