This example visualizes total COVID-19 cases over time using a bar chart, with each bar representing a date from the merged COVID and population CSV data. The React app loads merged_covid_population.csv via fetch, parses the rows into objects, and renders the chart with Recharts' BarChart, XAxis, YAxis, CartesianGrid, Tooltip, Legend, and ResponsiveContainer components. The y-axis shows total cases while the x-axis displays dates, and the single purple bar series uses the total_cases field. Data parsing is done manually through string splitting rather than D3's CSV utilities, though d3.v7 is included in the HTML.