This area chart visualizes world population growth from 1950 to 2015, using a smooth, filled curve to show the upward trend. The visualization is built with D3 v5, parsing CSV data and rendering to SVG. It uses `d3.scaleTime` and `d3.scaleLinear` for axes, `d3.axisLeft`, `d3.axisBottom` for ticks, `d3.area` with a basis curve for the filled region, and grid lines via tick sizes.