Gian Giorgio Trissino (1478-1550) was an Italian poet, playwright, and humanist from the region of Vicenza. He is best known for his contributions to the development of the Italian language and literature during the Renaissance. Trissino's works often focused on themes of love and morality, and he played a significant role in promoting the use of the vernacular in literary expression. In addition to his literary achievements, Trissino was also a prominent figure in the world of theater and drama. He is credited with introducing the concept of the five-act structure in Italian plays, which influenced many playwrights, including Ludovico Ariosto. His efforts helped shape the future of Italian literature and drama, leaving a lasting legacy.