My wordpress video blog have several categories. Lets say the category can belong to several genres e.g actions,horror,mystery and another category belong to actions,horror,romance How do I group categories into genres? Cause in the most basic structure, we group posts into category. Now i want group categories into genres Then be able to display the category in the genre by a url such as http://www.domain.com/genre/actions and it will list all categories in it.