Data Object (DO) is an Object that is an instance of a Class of things used within a system. In Distributed Computing, the Data Object can either represent the class of things used by the Distributed Systems to support the distributed computing (i.e., transactions, blocks, etc.) or they can represent the class of things that will be distributed across the distributed computing network (i.e., supplies, cryptocurrencies, vehicle registrations, etc.).
Source: Reference Architecture (RA)