Leadership is hard to define and consequently there are a thousand different interpretations of what it really means. I would suggest thinking about a person that you would want to follow, a person that you would listen to if you were in a large group, and then think about why you picked that person.

At the most basic level, leadership is getting people to do something.
In my opinion, leadership is about influencing people to get a mission/ objective/ task completed to standard, but also while positively impacting those people. A good leader gives guidance, direction, purpose, and motivation to a given group of people to get the task at hand completed. A good leader also sets the example and joins in the work when the planning is completed and throughout the process whenever possible.

There are many different methods of doing this and that is where the study of leadership as an art/ science comes in to play - there is charismatic leadership, transformational leadership, task-oriented leadership, transactional leadership, et cetera.

Something to think about that may help is what's the difference between leadership and management? What is the difference between a leader and a boss or supervisor - the word leader certainly connotes a different meaning.

There is alot of stuff online that you can use as a jumping point

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My name is Alexia Wolker, I am a blogger and work as an editor. I have a Master's Degree in literature and love both reading and writing about books and literary topics like http://webklik.cz/zamestnani/61-worldventures.html