The tag to start the HTML document. Used in most documents. Other tags like <body> may be also used.
<html>
<head>
<title>Test webpage</title>
</head>
<body>
<h1>Hello, world!</h1>
<p>This is a example of a test page, you can check your browser if works with this!</p>
</body>
</html>
To post a link, lyrics, GIF, etc... of the most popular song Rick Astley - Never Gonna Give You Up, so others can see and say for example "You got Rick Rolled!" (that's the definition).
Search for "xcq" on Google, and will be seen with this YouTube video ID: dQw4w9WgXcQ, that's the point of Rick Rolling.