This D3.js line chart visualizes the trend of total global video game sales (in millions) per year, aggregating a CSV dataset by summing sales for each year after 1980. The chart uses `d3.select`, `d3.csv`, `d3.rollup`, and `d3.sum` for data loading and aggregation, then `d3.scaleLinear` for both axes, `d3.axisBottom` and `d3.axisLeft` for tick marks, and `d3.line` to generate the SVG path. The rendered SVG includes styled axis labels, a title, and a steelblue line.