This example displays three steel-blue circles on an 800-by-600 SVG canvas, with each circle’s position determined by the x and y coordinates from an external JSON file. The visualization loads data asynchronously using `d3.json`, then appends circles to the SVG via a D3 selection, iterating over the dataset with `.enter()`. The chart uses D3 v7’s declarative API to map data values directly to circle attributes.