The root element is used in HTML to denote the outermost element that organizes all the content of an HTML document. For example, in the code below, <html lang="en">
denotes the opening tag of the root element and </html>
denotes the closing tag of the root element.
<!DOCTYPE html>
<html lang="en">
<head>
...
</head>
<body>
...
</body>
</html>