Represents a data type such as Customer or Product in an external system application.
Assembly: Microsoft.SharePoint (in Microsoft.SharePoint.dll)
External content types contain identifiers, methods, and actions. External content types can also have other related external content types associated with them. For example, Customers and Order external content types in the AdventureWorks system have an association because they share a relationship: customers make orders. This relationship is implemented as an association in the metadata.
The business objects, for example, customer #88697 and order #1000 in the external system application, are referred to as external items. If your external content type maps to a database table, you can think of an external item as a row.