Military history texts discuss the historical record of armed conflict in the history of humanity, its impact on people, societies, and their cultures. Some fundamental subjects of military history study are the causes of war, its social and cultural foundations, military doctrines, logistics, leadership, technology, strategy, and tactics used, and how these have developed over time. Thematic divisions of military history may include: Ancient warfare, Medieval warfare, Gunpowder warfare, Industrial warfare, and Modern warfare.