Giovanni Boccaccio was an Italian writer, poet, and humanist of the late Middle Ages. He is best known for his work "The Decameron," a collection of 100 novellas that is considered a masterpiece of Italian literature. Boccaccio was also a friend and biographer of the poet Petrarch and was influential in the development of the Italian language. He is recognized as one of the founders of the Renaissance and is celebrated for his contributions to literature and humanism.