OPC Studio User's Guide and Reference
Primitive data
The primitive data is a value given in the underlying (.NET) type system. It is represented by an instance of the PrimitiveData Class.
The actual primitive value is stored in the Value Property and it can be any System.Object.
The OPC UA Complex Data extension contains intrinsic data type dictionaries that map specific standard and commonly used data types to primitive data types. For details, refer to OPC UA Data Type Systems.