This, very large tree is created using "dynamic initialization."
That means that the root of the tree is initially created, while
the other nodes are only created as the user opens the different
branches. This enables the very fast loading of very large trees.
Collapse all -- Collapse the whole tree and only show the top branches
Expand all -- Expand the tree and show all branches.
Toggle lines -- Hide/display the lines that connect the various nodes.

When you click on a node the following will be updated.
You can of course customize the code to take actions other than displaying the node.