This visualization displays population trends over time (1950-2100) for various regions, with each line colored by region name and sorted by final population value. It uses D3 v5 APIs including `scaleTime`, `scaleLinear`, `scaleOrdinal`, `nest`, `line` with `curveBasis`, and `axisLeft`/`axisBottom` to render axes. Data is loaded from UN population estimates via `csv` and processed through a custom `melt` function. The chart includes a color legend, axis labels, and uses SVG for rendering, with lines styled using mix-blend-mode multiply.