Part Modeling > Datum Features > Datum References > About Datum Reference Features and Intent Objects
  
About Datum Reference Features and Intent Objects
Datum reference features are user-defined surface sets, edge chains, datum planes, datum axes, datum points, or datum coordinate systems. Each datum reference feature can create an intent object, which you can use to show your design intent in a model.
You can construct one or more edge chains to create a chain datum reference feature. Construct one or more surface sets to create a surface datum reference feature. You can also use edge chains, or a combination of surfaces and edge chains, to define intent surfaces.
You can edit the definition of the selected datum reference feature or intent object, modify references, and change reference properties. You can redefine datum reference features created in an earlier version of Pro/ENGINEER. However, once you create a datum reference feature, you cannot redefine the type of intent object it creates.