This visualization displays a horizontal bar chart comparing types of chest pain against age counts from a heart attack dataset. The chart uses React to manage state and render SVG elements, while d3-scale functions (scaleBand and scaleLinear) map categorical pain types to y-axis bands and age values to x-axis positions. The data is loaded via d3.csv from a GitHub gist, filtered to the first 12 records, and mapped with a switch statement to rename chest pain codes into descriptive labels. The visualization highlights the distribution of different chest pain types across age groups.