"Avatar: The Last Airbender" depicts cultural diversity and representation by drawing inspiration from various real-world cultures such as East Asian, South Asian, Indigenous American, and Inuit cultures. The show features a diverse cast of characters with different cultural backgrounds, traditions, and beliefs. Additionally, the show addresses themes of imperialism, colonization, and the importance of understanding and respecting different cultures. Overall, "Avatar: The Last Airbender" showcases a rich tapestry of cultures and promotes the idea of unity through diversity.