The products in the Ecommerce are grouped by product types. The product types define common properties for the products of the respective type (e.g. delivery type). You can also create custom fields for each type that apply to the respective products. For example, the Book product class has a custom field named ISBN. For more information, see For developers: Product types.
The products in the Ecommerce API are represented by the Products class.
To manage departments, products, product types and product attributes, you use the Telerik.Sitefinity.Modules.Ecommerce.Catalog.CatalogManager class.