Your events can be placed in their own categories for better organization. If an event is not added to a category, it is placed in the "All" category by default. Adding categories is optional. If you don't create any, every event will go into the "All" category.
Master and Recurring Events
Every event has an [m] and [r] next to it. The [m] indicates a master event. It was placed in the calendar as a single event, which may have recurring events. The [r] indicates that the event is a recurring event. It has been created from a [m] master event.
Adding Calendar Categories
Click the “Category Setup” button on the top of the Calendar Menu. Enter the category name into the box and click "Add Category."