This bar chart displays the top 20 smartphone models by units sold, with each bar’s length representing millions of units and its color indicating the brand. Hovering reveals a tooltip with price, rating, and battery life. Built with React and D3 v5, it uses `scaleBand` and `scaleLinear` for axes, `scaleOrdinal` with `schemePastel1` for color, and parses a single-line CSV dataset via `csvParse` after normalization. The SVG renders with grid lines, tick labels, and value annotations.