This line chart displays one week of temperature data for multiple cities around the world, sourced from Data Canvas - Sense Your City. The visualization uses D3 v5 to render an SVG with a time-based x-axis and linear y-axis. Cities are color-coded via the `scaleOrdinal` and `schemeCategory10` APIs, with a custom legend built from `colorLegend`. The `nest` function groups data by city, while `scaleTime`, `scaleLinear`, `axisBottom`, `axisLeft`, and `line` with `curveBasis` generate the smoothed paths.