A bar chart displays population figures for nine countries, with steel-blue rectangles whose lengths encode each nation’s population. The chart uses D3 v5’s `scaleLinear` for the x-axis, `scaleBand` for the y-axis, and `axisLeft`/`axisBottom` to render ticks. Data loads from a CSV via `d3.csv`, and the SVG renders axis groups and rectangles through `append` and `enter` selections.