Making a Bar Chart
This bar chart displays the top 10 most populous countries using a horizontal layout, with population sizes mapped to bar widths and country names on the y-axis. The chart is built with D3 v6, using `scaleLinear` for the x-axis, `scaleBand` for the y-axis, and `axisBottom` and `axisLeft` for ticks. Data is loaded from a CSV file, and the chart is rendered as SVG. The visualization includes axis labels, a title, and a custom tick formatter that converts large numbers to billions.