A pie chart visualizes sales figures for ten car brands, with each slice's area proportional to the brand's sales value and labeled in a side legend showing both the car name and its corresponding number. The chart renders as an SVG using D3 v5, employing the `pie()` generator to compute arc angles from the loaded JSON data, `arc()` to create the paths, and `scaleOrdinal` with `schemeCategory10` to assign colors to slices. The legend is built manually with appended rectangles and text elements, while numeric values are formatted using D3's `format()` function.