This interactive scatter plot recreates the classic Gapminder visualization, mapping countries as circles over time, with income per capita on the x-axis, life expectancy on the y-axis, and population encoded by circle radius. Users can drag any country circle to explore its historical trajectory, which is drawn as a gray path connecting its annual data points. The code uses D3.js v3 for SVG rendering and animation, with a custom `dragit.js` library handling the drag-and-drop interaction and trajectory display. Data is loaded from a local `nations.json` file, and a slider lets viewers scrub through years from 1800 to 2008.