Architecting and designing : UML 2.0 Lite : UML models : UML Object Diagram
  
UML Object Diagram
A UML Object Diagram is drawn using the UML Class Diagram type. In the Object diagram, the user models the static structure of object interactions. An Object diagram is considered an instance of a class diagram; it shows a snapshot of the detailed state of a system at a point in time.
The Object diagram differs from the UML Collaboration diagram in that the Collaboration diagram shows the detailed state of a system over some period of time, including the changes that occur over time.
The Object and Link symbols from the UML Class diagram toolbar are used to construct an Object diagram.
See also
UML models