This example reproduces a static visualization using only SVG shapes, drawing a single vertical black rectangle on a white canvas. The code creates the SVG element via the raw Document Object Model (DOM) API, using `document.createElementNS` to set namespace attributes, and then appends a rectangle with fixed width, height, and x-coordinate. No external libraries are used, and the rendering is entirely procedural, with no data source or interaction. The visualization demonstrates basic SVG construction through native JavaScript methods.