Concept resources are descriptive entities similar to the object-oriented concept of a class. They describe a set of properties. For example, one concept might be Department, and it could include department name, manager, and employee properties.
Note: If you are working with a project imported from a release earlier than 5.0.0, you might be able to see metadata properties. However, do not use them. Instead use the settings and properties in the Domain Objects section of the CDD file as needed.