This example shows the simplest possible D3 output: a static text message, "Hello D3 version 6!", rendered directly into the page body at a large, centered font size. It demonstrates the minimal setup for starting a D3 version 6 project. The code uses the `d3.select` API to target the `body` element and the `text` method to set its string content. The page loads the D3 library from a CDN and runs a bundled JavaScript file, with the styling handled by plain CSS.