This example presents a scatterplot of the Iris dataset, visualizing petal length against sepal length with circular marks. The code uses D3 v7's `scaleLinear` to map data domains to pixel ranges, with margins applied to position the plot area. Axes are generated with `axisLeft` and `axisBottom` functions. The visualization is rendered as an SVG, with data loaded asynchronously via `d3.csv` from a remote gist URL, and point positions are computed and drawn using D3's selection and join operations.