Henri Fayol claims there are five functions of management: planning, organizing, leading, coordinating, and controlling. Today, management experts find Fayol's definition far too narrow, insisting that it excludes business administration and commercial management - two forms of management commonly practiced by managers in different sectors. Modern management theories have their roots in early writings. Sun Tzu's The Art of War, for example, may have been a military strategy book, but it provided the foundation behind the concept that there is a need to vary management approaches. Sun Tzu suggested acting on the strengths and weaknesses of both foes and one's organization. Niccolo Machiavelli pointed out in The Prince that leaders should use fear to maintain control. Meanwhile, Adam Smith outlines in The Wealth of Nations how work in an organization can be made more efficient through division of labor. Modern management has long since evolved from the basic principles of these writings. This section contains articles relating to management and the topics that are under its umbrella.