This horizontal barchart shows the population of the ten most populous countries, with values displayed in billions and sorted by descending population. The visualization uses D3 v6 APIs including `csv`, `scaleLinear`, `scaleBand`, `axisLeft`, and `axisBottom` to load data from a CSV file and render an SVG. Bars are drawn as colored rectangles, with gridlines extending from the x-axis and country labels on the y-axis.