This example visualizes the populations of the top 10 most populous countries as a horizontal bar chart, with data from the 2017 United Nations World Population Prospects. It shows how to customize D3 axes by removing default domain lines and tick lines, rotating tick labels, and adding custom axis labels using `d3.axisBottom` and `d3.axisLeft`. The code also formats population values using D3’s `format` function, replaces "G" with "B" for billions, and applies tick sizes and styling via CSS.