Filter categories
You use filter categories to classify the filters in your project. You can create as many filter categories as you like, then place individual filters into appropriate categories.
Categorising filters in this way makes it easier to find the filter you are looking for, for example when selecting a filter to apply to the active view. Whenever you select a filter, they are arranged into their categories, with any filters that do not belong to a category being displayed below the filter categories that do exist.
Once you have created a filter category in Library Explorer, you assign filters to the category by editing the properties of a filter and selecting the category in the Filter Properties dialog.
Filter categories do not have a Properties dialog; the only attribute is their name.