A circle follows the mouse cursor across an SVG canvas, moving smoothly in real time as the pointer travels. The visualization uses React state to track the cursor's x and y coordinates via an `onMouseMove` event handler, updating the circle's `cx` and `cy` attributes on every movement. Built with React 16.9 and rendered as a single SVG element with a fixed width and height, it demonstrates a simple interactive pattern without external data or animation libraries.