Object Diagrams

Object diagrams, or instance diagrams, illustrate objects and links. As in the case of class diagrams, object diagrams represent the static structure. The notation used for object diagrams is derived from that of class diagrams; elements that are instances are underlined.

Object diagrams are primarily used to show a context — before or after an interaction, for example. However, they are also used to aid the understanding of complex data structures, such as recursive structures.