I know that the HTML tag is used for attatching stylesheets, but looking at the W3CSchools tag reference, it has many other values for the rel attribute. I\'ve looked
Uh....
http://www.w3schools.com/TAGS/att_link_rel.asp
Basically, it's just a tag that says "other stuff needed for document is here", and the rel tag specifies exactly what that might be.
I know two prominent common uses:
With rel="stylesheet"
to reference external CSS style sheets
With rel="favicon"
to reference browser favicons
Additionally, there are
Forward and reverse links (rel="next"
)
Links to alternative resources for search engines (rel="alternate"
)
Check the W3C Reference: Links in HTML documents for details on stylesheet, and the latter two.
It links ;)
It's a way to say "this other resource and I (the HTML document) have a relationship."
The rel attribute says what the linked item is to the HTML document.
The rev attribute says what the HTML document is to the linked item.
So...
<link rel="stylesheet" href="style.css" />
Says "style.css is the style sheet for this HTML document."
Silly analogy: If HTML documents could be 'married' (in highly conservative no-same-sex-marriages) we could do something like this:
<link rel="wife" rev="husband" href="otherFile.html" />
With this element, the HTML document is saying that "otherFile.html is my wife, and I am its husband."
In addition to what Pekka said, I've seen it used for a pingback (rel="pingback"
) link, often used on blogs.
The <link> tag conveys relationship information. For stylesheets, that means "here are instructions on how to display this file", but links are used for semantic references of many kinds, including others not listed in the HTML spec.
In addition to all of the other answers, it's also used for RSS feeds.
For example: (From this very page)
<link rel="alternate" type="application/atom+xml"
title="Feed for question 'What does the HTML <link> tag do besides including stylesheets?'"
href="/feeds/question/2082362">