A dendrogram is a diagram that depicts hierarchical relationships. A dendrogram is often used to assign objects to groups.
The Flow Builder (Legacy) in Giraffe uses dendrogram assumptions. Transforms branch from the initiating geometry. And branch again. One shape becomes many. And the designer can visually track the inputs and outputs in an intuitive node-based editor.
The Flow Builder 2.0 has ported these existing transforms for use in the new node-based interface.