Tree diagrams can be used when a topic to be analyzed can be broken down into a simple, rigid hierarchy. In a tree diagram, each node may have zero, one or more children but may have only one parent (apart from the origin node which will have no parent).
The example given on the right is an analysis of business domains in a large organization. It was built as a strategic support for the subsequent modeling of information systems.
This is not an organization chart and does not set out to show how a company is organized, or its reporting lines.
~Organigrams or organization charts are often examples of tree diagrams, though when one person answers to two supervisors, or when dotted lines are included to show informal but important communication, the organigram will be an imperfect tree structure.