Vasari's masterpiece is his book, ""The Lives of the Great Architects, Painters and Sculptors of Italy"", first published in 1550. It is a book of biography. It tells the stories of the lives of Italian artists from Giotto who lived around 1300 to Michelangelo who was still alive when Vasari was writing his book. For some of the artists, very little is known about them except the stories that Vasari heard and wrote in his book. Even though nowadays it is known that Vasari sometimes made mistakes, he gives a wonderful picture of the characters of the artists, and tells all sorts of amusing stories.