What is the exposition In Rodrick rules?

In "Rodrick Rules," the second book of the "Diary of a Wimpy Kid" series by Jeff Kinney, the exposition introduces the main character, Greg Heffley, and his relationship with his older brother, Rodrick. The story is set in their family home and school, highlighting the dynamics of their household, particularly the tension and rivalry between the brothers. Greg's struggles with middle school life, friendships, and family expectations set the stage for the comedic challenges he faces throughout the narrative. This backdrop establishes the tone and themes of sibling rivalry and growing up.