This example shows the distribution of electric vehicles by vehicle segment using a D3.js pie chart. The visualization loads a CSV dataset from a GitHub Gist, aggregates vehicle counts per segment with `d3.rollups`, and renders slices with the `d3.arc` generator inside an SVG. Each slice is labeled with its segment name and count, and a legend lists the segments with colors from `d3.schemeSet2`. The chart uses `d3.csv`, `d3.pie`, and `d3.scaleOrdinal` to transform the data into a clear, annotated visualization.