This interactive collapsible tree visualizes a hierarchical dataset of software modules, showing parent-child relationships that expand and collapse when nodes are clicked. The tree uses d3.tree for layout, d3.linkHorizontal for curved connecting paths, and d3.zoom for panning and scaling. Nodes and links transition smoothly over 250 milliseconds via d3 transitions, with node colors distinguishing leaf nodes from branches. Data comes from the flare-2.json file, which contains nested name and value properties.