In the book "Salt: A World History" by Mark Kurlansky, the author explores the impact of salt on civilization throughout history. The book covers a wide range of topics, including the use of salt for food preservation, its role in taxation and control by world powers, and the darker side of salt production, including slavery. While the book primarily focuses on historical saltmaking, it also touches on the development of iodized salt and the industrialization of food production. "Salt: A World History" provides readers with a comprehensive analysis of the influence of salt on human societies.