This example displays the classic Iris dataset as a scatterplot, plotting sepal width on the x-axis and sepal length on the y-axis. The code loads the data from a CSV URL and uses d3.csv to parse it, then constructs linear scales with d3.scaleLinear to map the data to screen coordinates. It renders circular marks via SVG circle elements and adds axes using d3.axisLeft and d3.axisBottom. The visualization is built with React, though the core charting logic relies entirely on D3 v7.