This example shows a week of temperature readings in San Francisco, plotting each observation as a red semi-transparent circle on a scatterplot with time on the x-axis and temperature on the y-axis. The visualization uses d3.csv to load the data, d3.scaleTime and d3.scaleLinear for scaling, and d3.axisBottom with d3.axisLeft to render gridlines and tick marks. SVG circles are appended to the chart, with a title and rotated axis labels, all styled via external CSS.