This example displays a temperature-over-time line chart for San Francisco, plotting daily temperature readings as a connected path with circular markers. The visualization uses React for component structure, with D3 v5 scales for mapping data to coordinates. The line and circles are rendered as SVG elements, while `d3.scaleTime()`, `d3.scaleLinear()`, and `d3.extent()` handle the x and y axis domains. The data comes from a CSV file fetched via D3’s `csv` method, and both axes are customized with tick marks and labels using D3’s `line()` generator.