What is a Tree Diagram?

The tree layout

The “Tree layout” is not a distinct type of diagram, per se. Instead, it’s representative of D3’s family of hierarchical layouts.

It’s designed to produce a “node-link” diagram that lays out the connection between nodes in a method that displays the relationship of one node to another in a parent-child fashion.

For example, the following diagram shows a root node (the starting position) labeled “Top Node,” which has two children (Bob: Child of Top Node and Sally: Child of Top Node). Subsequently, “Bob: Child of Top Node” has two dependent nodes (children), which are “Son of Bob” and “Daughter of Bob.”