What is the author's style in The Man Who Knew Infinity: A Life of the Genius, Ramanujan by Robert Kanigel?

The Man Who Knew Infinity is written from the perspective of the layman attempting to understand the relationship of two mathematical geniuses and their interactions with the world around them. The main interest of the author is not to explain or laud either Ramanujan's or Hardy's work, but rather to explain their significance in history. In many ways, Hardy and Ramanujan were worlds apart. Hardy, although he came from a middle class background, attended and was a product of the most exclusive schools in England, Winchester, and Cambridge.