This bar chart displays the populations of the top 30 countries in 2020, sorted in descending order. The chart uses d3.scaleLinear for the x-axis and d3.scaleBand for the y-axis, with data loaded via d3.csv from a GitHub-hosted CSV file. SVG rectangles represent the bars, and d3.axisBottom and d3.axisLeft render the ticks. The code formats population values using d3.format, and tooltips show the exact population on hover.