This example visualizes vehicle fuel efficiency using an interactive scatter plot of the Auto MPG dataset, where each point represents a car with its miles per gallon on the x-axis, horsepower on the y-axis, color encoding country of origin, and point size indicating weight. The visualization is built using the Vega-Lite API, which registers with Vega and Vega-Lite to render the chart as SVG, while D3.js loads the CSV data asynchronously. The code configures axis styles, tooltips through the Vega Tooltip handler, and automatically sizes the chart to fill the window.