This area chart visualizes population distribution across four regional parts for eight selected countries, using filled areas to show population magnitude. Built with D3 v7, the SVG chart loads data from a TSV file and uses d3.group, d3.scaleLinear, and d3.scaleOrdinal to process and map the values. Interactive features include hover effects on areas, dots, and legend items, plus a tooltip, with color-coded series and grid lines for readability.