Managing linked categories
If you are creating or updating a sales catalog, you might want to link a category from the master catalog to a sales catalog or from one sales catalog to another. For example, a Winter Coats category in the master catalog could be linked to the Coats category in the Winter Specials sales catalog. Linking helps to keep categories consistent. For example, when you add a product to the original category, the categories that are linked to the original category will also see the product that was added.
When you link a category, you are still referencing the original category, and any changes you make to it will be reflected in the link. When you copy a category, a new category is created with most data content of the original content, and any changes you make to the original category is not reflected in the copy.