This example displays the text “Hello HTML” in the center of a plain web page, with the font size set to an extremely large 13em. It serves as a minimal demonstration of a basic HTML document structure, including a `<head>` section with embedded CSS styling and a `<body>` containing the visible content. The page relies solely on standard HTML and CSS, with no external libraries or JavaScript, making it a bare-bones starting point for web development. The styling is applied globally to the body element, centering the text horizontally.