This bar chart displays the wealth of billionaires, grouped by company name, with bar heights and colors scaled to each billionaire’s net worth in billions of dollars. Built with D3 v6 and React, the visualization loads CSV data from a GitHub gist, uses `d3.scaleBand` and `d3.scaleLinear` for axes, and renders bars as SVG rectangles with hover effects via CSS. Axes are drawn using `d3.axisBottom` and `d3.axisLeft`, and each bar includes a tooltip title showing its value.