This area chart visualizes global population growth over time, with years on the x-axis and population on the y-axis, using a smooth filled curve to show trends. The code employs d3’s `area`, `scaleTime`, `scaleLinear`, and `axisLeft`/`axisBottom` APIs to render the SVG, while formatting y-axis labels in billions. Data is loaded from a CSV file and parsed into date and numeric values. The chart includes custom axis styling, grid lines, and a centered title.