A pie chart displays the market share of car brands for 2021, with each slice representing a company's total sales and hover interactions revealing the exact value and percentage. The visualization is built with Plotly, using its `newPlot` function to render the chart inside a designated HTML `<div>` element. It fetches a CSV dataset from a GitHub repository, parses the file by splitting rows and columns, and extracts the brand names and total sales figures to populate the chart's labels and values. The layout sets the title, height, and width for the final presentation.