A hierarchical tree visualization maps a taxonomy of digital devices and their associated activities, such as smartphones leading to communication, and laptops branching into entertainment with subcategories like Danceshows and Cricket. The layout is generated with D3.js v6’s `d3.stratify()` and `d3.tree()`, while `d3.linkVertical()` draws the connecting paths. Each node is rendered as an SVG rectangle labeled with its feature name, and the fill color—assigned by the `setGeneration` function—varies by tree depth, from purple at the root to yellow for the deepest leaf nodes. The data is defined inline as a JavaScript array of parent-child pairs.