Creating and deleting brush categories
You can create a brush category to store new brush variants or to organize existing variants for a specific workflow or project. You can also delete a brush category.
To create a new brush category
The new brush category appears in the Brush Category list of the Brush Selector and contains the currently selected brush variant, because a brush category must contain at least one brush variant.
You can also change the brush category icon by right-clicking a category in the Brush Selector, choosing Set Custom Icon, and choosing the image that you want to display as the category icon.
You can also create a new brush category from the Brush Selector by clicking the Brush library options button 
and choosing New Brush Category.
To remove a brush category
You cannot remove any of the default Painter brush categories.
You can also remove a brush category from the Brush Selector by clicking the Brush library options button and choosing Remove Brush Category.