|Merchandising Fundamentals / Catalog Fundamentals|
Custom catalogs aggregate base catalogs and set special pricing rules. Custom catalogs can apply different currencies for products and categories while preserving the original base catalog. You can also use Custom catalogs to create language-specific catalogs and sale catalogs.
If you add a product to a base catalog, the product may also appear in the associated Custom catalog, depending on the inclusion rules. Products in a Custom catalog are represented only one time in the database, regardless of how many Custom catalogs they appear in. Custom catalogs can have their own category hierarchy, which makes them a flexible way to organize your products for different audiences.