In a CASE tool, for example, these would connect each occurrence of an item in the requirements document, design documents, program code, documentation and system output. In a GIS, one should be able to see every occurrence of a data value or geographic object in all maps, data listings and analysis reports. Occurrence relationships would also link different versions of the same document or datum. Annotative Relationships Relationships declared by the user in addition to those above. While all the aforementioned relationships could be generated automatically based on the application or system structure, annotations allow the user to declare anything not inferable or automatable.
Annotations range from comments on single items to user-declared ad hoc links between items.
For example, team members should be able to annotate each others' annotations. Similarly, they should have access to all occurrences of any relationship in the system. Providing such information supports the goal of many organizations to empower lower-level employees with decision making capabilities. On the other hand, in certain domains developers may deem such access irrelevant or even distracting to the user's task, possibly slowing down time-critical operations. The user typically selects an item on the computer screen to follow its link or chooses from a list of available links.