This visualization displays a pie chart of the Air Quality Index by country, using a categorical color scale to distinguish slices and an accompanying legend with country names and index values. Data is loaded from a CSV hosted on GitHub, with numeric conversion and sorting by index before rendering. The chart uses D3 v5 APIs including `pie()`, `arc()`, `scaleOrdinal` with `schemeCategory10`, and `select`/`append` to build the SVG output.