The Head Element
The head element contains general information, also called meta-information, about
a document. Meta means "information about".
You can say that meta-data means information about data, or meta-information means information about information.
Information Inside the Head Element
The elements inside the head element should not be displayed by a browser.
According to
the HTML standard, only a few tags are legal inside the head
section. These are: <base>, <link>, <meta>, <title>, <style>,
and <script>.
Look at the following illegal construct:
<head>
<p>This is some text</p>
</head>
|
In this case the browser has two options:
- Display the text because it is inside a paragraph element
- Hide the text because it is inside a head element
If you put an HTML element like <h1> or <p> inside a head element
like this, most browsers will display it, even if it is illegal.
Should browsers forgive you for errors like this? We don't think so. Others
do.
Head Tags
| Tag |
Description |
| <head> |
Defines information about the document |
| <title> |
Defines the document title |
| <base> |
Defines a base URL for all the links on a page |
| <link> |
Defines a resource reference |
| <meta> |
Defines meta information |
| Tag |
Description |
| <!DOCTYPE> |
Defines the document type. This tag goes before the <html> start tag. |
The Meta Element
As we explained in the previous chapter, the head element contains general
information (meta-information) about
a document.
HTML also includes a meta element that goes inside the head element. The
purpose of the meta element is to provide meta-information about the document.
Most often the meta element is used to provide information that is relevant
to browsers or search engines like
describing the content of your document.
Note: W3C states that "Some user agents support the use of META to
refresh the current page after a specified number of seconds, with the option of
replacing it by a different URI. Authors should not use this technique to
forward users to different pages, as this makes the page inaccessible to some
users. Instead, automatic page forwarding should be done using server-side
redirects" at
http://www.w3.org/TR/html4/struct/global.html#adef-http-equiv.
Keywords for Search Engines
Some search engines on the WWW will use the name and content attributes of
the meta tag to index your pages.
| This meta element defines a description of your page:
<meta name="description" content="Free Web tutorials
on HTML, CSS, XML, and XHTML">
|
| This meta element defines keywords for your page:
<meta name="keywords" content="HTML, DHTML, CSS, XML,
XHTML, JavaScript, VBScript">
|
The intention of the name and content attributes is to describe the content of
a page.
However, since too many webmasters have used meta tags for spamming, like
repeating keywords to give pages a higher ranking, some search engines have stopped using them entirely.
You can read more about search engines in our Web
Building Tutorial.
Unknown Meta Attributes
Sometimes you will see meta attributes that are unknown to you like this:
| <meta name="security" content="low">
|
Then you just have to accept that this is something unique to the site or to the
author of the site, and that it has probably no relevance to you.
You can see a complete list of the meta element attributes in our
Complete
HTML 4.01 Tag Reference.
