This example demonstrates basic SVG shape creation within an HTML page. It renders two circles on a 960-by-500 pixel canvas, with the first circle using default black fill and the second explicitly colored violet. The code uses raw SVG markup directly in the `index.html` file, showing how to set the `cx`, `cy`, and `r` attributes for positioning and sizing. No external libraries are used; the visualization relies purely on inline SVG elements within the browser's HTML rendering.