Updates category structure to old pre-2.3 from new taxonomy structure.

Checks if a category is an ancestor of another category.

Removes the category cache data based on ID.

Retrieves the ID of a category from its name.

Retrieves the name of a category from its ID.

Retrieves a list of category objects.

Retrieves category data given a category ID or category object.

Retrieves a category based on URL containing the category slug.

Retrieves a category object by category slug.

Retrieves a post tag by tag ID or tag object.