This interactive network graph visualizes the relationships between COVID-19, its variants, and associated symptoms. Nodes representing concepts like "Delta Variant" and "Fever" are positioned using a force-directed layout, with connecting lines (links) whose thickness corresponds to a weight value. The visualization uses the D3.js v4 library, specifically leveraging the `d3.forceSimulation` API for physics-based node placement and the `d3.json` method to load hierarchical data from a local `data.json` file. Rendered as an SVG with custom styling, the graph allows users to drag nodes, revealing the interconnected structure of the topic.