A donut chart displays the distribution of music genres by percentage, with each slice labeled and colored distinctly. The visualization uses D3.js to load CSV data and render an SVG, employing `d3.pie` and `d3.arc` for the donut geometry, `d3.scaleOrdinal` with a custom color range, and d3-scale-chromatic for color handling. Hovering over a slice reveals a tooltip showing the precise percentage, calculated with `d3.sum`, while mouse events and CSS transitions manage tooltip visibility.