This scatter plot visualizes the Iris dataset, showing petal length versus petal width as colored circles for three species (setosa, versicolor, and virginica). The code loads CSV data from a GitHub gist and uses D3 v6 APIs such as `scaleLinear`, `axisBottom`, and `axisLeft` to construct the axes. Circles are rendered via SVG and colored by species with a switch-based marker function. The layout fills the entire browser window, with axis labels indicating petal dimensions, while sepal measurements are stored but not visually mapped.