This bar chart shows the populations of the top 10 most populous countries in 2018, sourced from the United Nations World Population Prospects. The horizontal bars are ordered by country name, with a linear x-axis and a banded y-axis. The code uses D3 v5’s `scaleLinear`, `scaleBand`, `axisBottom`, and `axisLeft` to draw axes, while custom tick formatting converts large numbers into abbreviated units like “B” for billions. The x-axis gridlines extend across the chart via negative tick sizes, and the axis labels and title are styled with CSS.