|An article is content that is typically organized by category or keyword.
|A blog is content that is typically presented as reverse chronologically sorted on a single topic.
|A category organizes other items and is contained in a hierarchy.
|Abstract base class.
|A line item contains a single Item and the quantity that was ordered.
|Location to associate with an Item, for example for filtering reasons if a product only available in an area.
|An order sent upon user checkout.
|A product is a CategorizedItem that can be sold to users.
|A user-created review of an item.
|Additional tags about an item such as Brand for products or Author and Keywords for articles.
|Modifies how items will be selected and ordered for promotion.
|Specifies which type a tag belongs to.