A category is a means to group your events or other categories together. In Agenda 'Home' is the top level category in which you start from. Inside a category you can add events or other subcategories, set access rights to say who can access or modify, re-allocate the sub- categories, remove the sub-categories and also delete the current category and everything it has inside it. These features are accessible through 'modify' (if you have modification rights) on the Tools menu inside the category. You will then be in the Management Area for Category.