<!DOCTYPE html>
<html>
<head>
<title>Add Node Example</title>
</head>
<body>
<button onclick="addNewParagraph()">Add Paragraph</button>
<script>
function addNewParagraph() {
let newNode = document.createElement('p');
newNode.textContent = 'This is a new paragraph.';
document.body.appendChild(newNode);
}
</script>
</body>
</html>