This bar chart displays the population of the top 10 most populous countries, based on 2018 United Nations estimates. It uses D3 v5 to create a horizontal bar chart with SVG, employing `scaleLinear` and `scaleBand` for positioning. The chart customizes D3 axes by removing default tick lines, adding tick marks across the plot, and formatting population numbers using `format('.3s')` to convert values to billions. It also includes custom axis labels and a title, with country names on the y-axis and population values on the x-axis.