This visualization presents a hierarchical tree of world countries, organized by continent and subregion, using a left-to-right node-link diagram. The d3.js library builds the tree layout, positions nodes with `tree()` and `hierarchy()`, and draws curved link paths via `linkHorizontal()`. Node labels are placed at varying font sizes based on their depth. The data is loaded from a local `data.json` file and rendered as an SVG, with zoom functionality enabled through a d3 zoom event handler.