Nana is a popular Japanese manga series written and illustrated by Ai Yazawa. It follows the lives of two young women, both named Nana, who meet by chance on a train to Tokyo. Despite their different personalities and backgrounds, they form a deep friendship as they navigate love, dreams, and the challenges of adulthood. The manga explores themes of friendship, romance, and the struggles of pursuing one's aspirations in the music industry. It has been well-received for its relatable characters and emotional storytelling, leading to adaptations in both anime and live-action films.