Based on the info provided, this appears to be a hyperbolic tree.
- central node
- exponential node increases
A hyperbolic tree defines a graph drawing method inspired by
Displaying hierarchical data as a tree suffers from visual clutter as
the number of nodes per level can grow exponentially. For a simple
binary tree, the maximum number of nodes at a level n is 2n, while the
number of nodes for larger trees grows much more quickly.
Drawing the tree as a node-link diagram thus requires exponential
amounts of space to be displayed.
quote and example from the data viz project.
The interactivity of clicking to get information about a specific node is simply a good practice for any digital info visualization.