This bar chart displays the population of the top 10 most populous countries, using 2018 estimates from the United Nations World Population Prospects. It shows how D3 axes can be customized: the x-axis uses a custom tick format to abbreviate large numbers (converting G to B), and grid lines extend across the chart. The y-axis removes its domain line and tick marks for a cleaner look. The visualization is built with d3.scaleLinear, d3.scaleBand, d3.axisBottom, and d3.csv, rendering as SVG.