This bar chart visualizes the population of the top 30 countries in 2020 using a horizontal layout, with country names on the y-axis and population values on the x-axis. The data is loaded from a Gist CSV file via d3.csv, then sorted and sliced to select the top entries. The visualization uses d3.scaleLinear and d3.scaleBand to map values, while SVG rectangles render the bars. Interactive hover effects change bar colors from light green to orange, and axes are generated using d3.axisBottom and d3.axisLeft.