The scatterplot shows the population density of London boroughs by plotting each borough's population (x-axis) against its area in hectares (y-axis) as animated circles that drop into place. The visualization uses D3 v3 to read the CSV data, applies linear scales for both axes, and employs the `d3.csv` parser and `d3.svg.axis` for the chart. Each circle is rendered as an SVG element, with a hover effect that turns it CornflowerBlue. Data is sourced from data.london.gov.uk, and the animation uses sequential delays to drop the circles over two seconds.