---- H ----
<hn>
heading tags<head>
tag<header>
tag- heading tags
<hgroup>
taghidden
global attribute- horizontal rule tag
<hr>
tag- HTML comments
<html>
tag- hypertext link
- or hyperlink, for short
<hn>
heading tags<head>
tag<header>
tag<hgroup>
taghidden
global attribute<hr>
tag<html>
tag