Use <link>s in your document
the LINK element
HTML and XHTML have a mechanism which gives the possibility to Web authors to add external information related to the HTML document. These external resources can be styling information (CSS), help for navigation, information under another form (RSS), contact information, etc.
The LINK
element (<link>
) is used to add this information in the header of your document in the HEAD
element.
Examples
Let's see a practical example, with one page of an astronomy Web site. The page is about the planet Earth in a section which describes the solar system.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> <head> <title>Earth - Astronomy Weblog</title>
The classical start of an HTML document.
<link rel="Start" href="/solar-system/" /> <link rel="Prev" href="/solar-system/venus/" /> <link rel="Next" href="/solar-system/mars/" />
These links will help for the navigation in certain user agents.
-
Start
gives the starting point of the section -
Prev
gives the previous item, here the planet Venus -
Next
gives the next item, here the planet Mars
<link rel="Contents" href="/solar-system/contents.html" />
Contents
points to the index of the section
<link rel="Help" href="/website-help.html" />
Help
gives the possibility to link to a page helping your visitors use
your Web site.
<link rel="alternate" type="application/rss+xml" title="RSS" href="/updates.rdf" />
It gives the possibility to RSS Readers to find the Web site updates feed. Note that, at the time of this writing, the mime-type application/rss+xml
is still a draft "The application/rss+xml Media Type" and is not yet accepted by IETF.
<link rel="meta" type="application/rdf+xml" title="FOAF" href="http://astro.example.org/foaf.xrdf" />
It gives the possibility to FOAF Readers to find the metadata on document. It could be the author. Note that, at the time of this writing, the mime-type application/rdf+xml
is not yet accepted by IETF and there were no further work on it since the last proposal.
<link href="mailto:[email protected]" rev="made" />
A way to contact the author of the Web site
<link rel="stylesheet" type="text/css" media="screen" href="/style/astro.css" />
Specify the CSS to display your Web site. For example in this link, we have specified that the stylesheet was for screen rendering. We could have other stylesheets for other media.
<link rel="alternate" href="/solar-system/earth.fr" hreflang="fr" title="French Translation" />
It gives you access to a translation of the document in another language, in this case French.
</head> <body> .... Here the rest of the page.
It closes the header section and opens the body section.
These links are used by user agents (browsers) and other applications to help people use your website.
Further Reading
- HTML 4.01: Description of the LINK element (The semantics of the element is the same for XHTML 1.0)
- HTML 3.2: LINK element
- Description of the link types
- Dive into accessibility: Provide additional navigation aids
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