This example shows a horizontal bar chart of population data for 30 countries in the year 2000, using a green bar for each country’s population value with a tooltip on hover. The bars are rendered as SVG rectangles via React, while the axes are built with D3’s `scaleBand` and `scaleLinear` for positioning. Data is loaded from a CSV file using `d3.csv`, and tick labels are formatted with `d3.format` to abbreviate large numbers (e.g., converting “G” to “B”).