This example demonstrates a minimal bar chart template using D3, rendering four country population values as equal-sized squares. The SVG canvas is initialized with fixed dimensions, and the code loads data from a CSV file via `d3.csv`. Each rectangle is appended using the data join pattern (`.selectAll('rect').data(data).enter().append('rect')`), though all bars share the same 300×300 size. The visualization relies on D3 v6’s module imports, `select` and `csv`, to process the data and update the DOM without any scales or axes.