A horizontal bar chart displays the ten most populous countries using data from a CSV file. Population values are formatted with D3's `format` shorthand, converting gigabytes to billions (e.g., "1.41B"). The chart uses `scaleLinear` for the x-axis and `scaleBand` for the y-axis. D3's `axisBottom` and `axisLeft` generate custom axes, with grid lines and tick styling, all rendered as SVG.