How to make business domain model

1. Domain model is a visual dictionary of abstraction.
2. There are two strategies to identify conceptual class:

• Use a conceptual category list. (see Page 144 )
• Find conceptual class with noun phase identication

    3. If we don't think of one business model as number or text, it's a conceptual class rather than attribute.

    4. When are specification conceptual classes  required.
  
        1>There needs  to be a description about an item or service, indepent of current existence of the item and service.
        2>Deleting the instance of things they descriped will consult in the informatino loss which need to be maitaned.
        3>It reduced the reduntant and duplicated information,