What is the difference between leadership and management?
I would say that leadership is one aspect of management, but it is not the only aspect. It is the part of management that is more of an "art" while other parts of management are more of a "science."
Good managers must be leaders. That is, they must be able to inspire their subordinates to be productive during their working hours. If a group of employees is not well-led, its productivity will suffer. This is leadership -- the ability to influence people to do their best.
But this is not all that a manager must do. A manager must also be proficient at things that do not have to do with leadership -- things like setting up efficient work routines, having a good knowledge of the production process, knowing how to manage inventory. All of these things, and more, are part of management but not really part of leadership.
Managers, particularly those managing the work performed by large number of people also need to be good leaders to be able to manage effectively. Likewise leaders also need to have good managerial skills. Thus there is a lot that is common between leadership and management. However the two are not identical.
Management focuses on making work effective, and in this process uses some leadership skills and functions to influence the activities of the persons performing the work. But leadership covers many other functions, which are not necessarily part of management. For example, a leader may work for the betterment of the people that he or she leads, rather than for achieving any specific tasks performed by the group. In doing this kind of work the leader may just guide and inspire the followers into action without actually managing their detailed activity. For example, Mahatma Gandhi inspired billions of Indians to struggle for freedom of India and to improve the economic and social condition of common people. But he did not manage the activities of all these people.
Leaders do manage their own activities and of their close associates. Unless leaders they do this effectively, they cannot win the respect and support of their followers. However, their role goes much beyond these managing activity.
Similarly, managers use leadership tools and techniques to guide and motivate the people working under them, but they also perform many other functions. For example, managers need to regularly plan, monitor and control all the activities of their subordinates. Further the managers are responsible for achieving the objectives of the work they manage. This work objective is different from the objectives of the subordinates. The focus of manager is the work objective. They are concerned with the personal objectives of the subordinates only to the extent it affect the work objectives. In contrast, leaders are not concerned with any objectives independent of the followers. The leader influences the followers to adopt and work only for such common personal objectives of followers. There are no other work objectives. Thus a leader works towards influencing and achieving worthwhile objectives of the followers, whereas, a manager focuses on the achievement of organizational objective.