Managing Catalog and Inventory Schema
A Commerce Server 2009 schema contains three types of definitions: property definitions, category definitions, and product definitions. If you decide to create your own catalog instead of importing one, you must first create these definitions. After you create product and category definitions, you can add categories and products to the catalog. You can edit the catalog metadata, property metadata, inventory catalog metadata, and inventory SKU metadata.
After you create your catalog item definitions, you can enter data for individual categories and products by using Catalog Manager.