This bar chart displays the population of the top 10 most populous countries using data from the United Nations World Population Prospects 2017. It builds on a basic bar chart by customizing the axes: the x-axis uses a linear scale with tick labels formatted as billions (e.g., “1.2B”), while the y-axis removes tick lines and the domain. The example uses D3 v5 APIs such as `d3.scaleLinear`, `d3.scaleBand`, `d3.axisBottom`, and `d3.axisLeft` to render the SVG. Axis labels, grid lines, and title styling are applied via CSS.