This example combines a React "Hello vega" message with a Vega-embedded bar chart. The page imports React and ReactDOM via UMD, using `createRoot` to render a simple component into the `#root` div. Simultaneously, it uses the `vegaEmbed` API to load a bar-chart specification from a remote GitHub URL and render it into the `#vis` div. The visualization displays a standard bar chart sourced from the Vega example gallery, with styling that enlarges the text message.