This interactive tree visualization explores the Medical Subject Headings (MeSH) hierarchy, using a force-directed layout to display the relationships between medical categories and their sub-terms. Built with D3.js v6 and React, the tree is rendered as SVG elements, with animated transitions when nodes are clicked to expand or collapse child categories. The code processes flat MeSH data into a hierarchical structure, categorizing entries based on regex patterns matching their descriptions. Users can navigate through the tree by clicking nodes, which triggers smooth animations and displays node-specific information in a floating div.