This example shows the population of 20 countries in 2010 as a horizontal bar chart. The chart uses D3’s scaleBand and scaleLinear to map countries to y-axis positions and population values to bar widths, rendered as SVG rectangles. React manages the component state and lifecycle, while D3’s csv function loads the population data from a GitHub-hosted CSV file. Axis components generate tick marks and labels, and a tooltip displays the formatted population value for each bar.