A line chart plots San Francisco temperature readings over a week, using a natural curve to connect daily data points from the Data Canvas Sense Your City dataset. The React app loads CSV data with d3.csv, maps timestamps with `scaleTime`, and maps temperature values with `scaleLinear`. SVG rendering uses React components for axes and marks, while d3's `line` generator with `curveNatural` draws the path, and native SVG `<title>` elements provide tooltips.