1. MetaTag Introduction: Meta-data can be entered into an html document by placing metatags in the head of the document. The servers can then use the data to identify the html content. MetaTags allow document cataloging.
2. MetaTag Definition: META elements are placed within the HEAD element to describe document information from the HTML content. The information can be extracted by servers for use in identifying, indexing and cataloging document content.
It is common practice to use named elements that have well defined semantics for each type of meta-data. HTTP servers can then read the contents of the document head to identify the html content and to generate response headers corresponding to the meta elements with the attribute HTTP-EQUIV. This provides document authors with a mechanism for identifying information that should be included in the response headers of an HTTP request.
The META element has three attributes:
NAME
CONTENT
HTTP-EQUIV
3. NAME: The name attribute can be used to define properties such as author, language, keywords etc.
An example:
<META NAME= "Editor" CONTENT = "John Smith">
4. CONTENT: Used to supply a value for a named property. If it's used with the HTTP-EQUIV it can contain more than a single element; met-data will use the Boolean operators (AND, OR) intrinsically. The AND operator is represented by a "SPACE" (ASCII[32]) and the OR operator by a "COMMA" (ASCII[44]). The AND operator is processed before the OR operator. So a string like this: "Red Coat, Blue Coat" equates to :"Coat AND (red OR Blue)".
5. HTTP - EQUIV: This attribute binds the element to an HTTP header. If the semantics of the HTTP header named by this attribute is known, then the contents can be processed based on well defined protocols.
An HTTP Header is: "A record sent by clients and servers communicating with each other via the HTTP protocol. The header is a stream of text that may be sent without any content following it or with the content that it describes. There are headers specific to requests and to responses and others that are used for both client and server, to describe or query the content or html environment. An example of a common request header, sent to the server, is If-Modified-Since. The server returns the file only if it has been changed since a certain date and time."
HTTP header names are not case sensitive, however common practice is to make the first letter of a header name to be capitalized. It is possible to use any text string, but if you want to be well defined, these properties will have to use the following well defined words:
Refresh : to indicate when to refresh a page
Copyright : to indicate if a copyright is held.
Content-Type : to indicate text/html; and the language
charset=ISO-8859-1
Timestamp : to indicate when the document is authored
Expire : to indicate the expire date of the document
Content-Language : to indicate the language of the document
Abstract : to indicate the abstract of the document
Organization : to indicate the organization of the author
Revision : to indicate the revision number of the document
Public : to indicate if the document is available to the public.
Last Modified : to indicate the last time a document
or article has been Modified.
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<meta name="description" content="Resource for vacations.">
<meta name="keywords" content="travel,agency,travel agency,
vacations,travel resource">
<meta http-equiv="Content-Type" content="text/html; charset=ISO-
8859-1">
<meta name="resource-type" content="Document"/>
<meta name="DocumentCountryCode" content="us"/>
<meta http-equiv="Content-Language" content="en">
<meta name="Language" content="en"/>
<meta name="classification" content="Internet"/>
<meta name="distribution" content="Global"/>
<meta name="rating" content="General">
<meta name="Author" content="Tech Systems.com"/>
<meta http-equiv="copyright" content="PortalDepot.net"/>
<meta name="revisit-after" content="10 days"/>
<meta name="robots" content="all"/>
These are tipicle MetaTags to place in the head of an "Article Page" document.
<meta name="description" content="Where To Put Your
Advertising Dollars" />
<meta name="keywords" content="web promotion,website
advertising,website marketing" />
<meta http-equiv="Content-Type" content="text/html; charset=iso-
8859-1"/>
<meta name="resource-type" content="Document" />
<meta name="type" content="article" />
<meta name="Language" content="en"/>
<meta name="DocumentCountryCode" content="us"/>
<meta name="distribution" content="Global"/>
<meta name="rating" content="General">
<meta name="Author" content="Tech Systems.com"/>
<meta http-equiv="pubdate" content="20050409"/>
<meta http-equiv="Last Modified" content="Wed, 26 Feb 2005
08:21:57 gmt">
<meta http-equiv="copyright" content="TechSystems.com"/>
<meta name="ROBOTS" content="all">
These are Robot Meta Commands, that tell the search engines wether to index a page or not and wether to follow any hyperlinks, within the page.
<meta name="ROBOTS" content="all">
<meta name="ROBOTS" content="none">
<meta name="ROBOTS" content="index">
<meta name="ROBOTS" content="index,follow">
<meta name="ROBOTS" content="noindex,follow">
<meta name="ROBOTS" content="noindex,nofollow">
MISCILLANIOUS METATAG COMMANDS
<meta name="creation_date" content="9/1/2003">
<meta name="Reply-to" content="admin@spiderweblogic.com">
This command tells the search engines to spider your document every 10 days.
<meta name="revisit-after" content="10 days"/>
This command tells the search engines not to spider your document for harvesting email addresses.
<meta name="no-email-collection" value="http://portaldepot.com/nospam.html"/>
This command tells the search engines not to cache your document. Its use is intended when you are making a lot of changes to your document.
<meta http-equiv="Pragma" content="no-cache">
Disables IE 6 Image Toolbar for copying images.
<meta http-equiv="imagetoolbar" content="no">
These are filters developed by MS to fadein web pages. They are ignored by all browsers other then IE Browsers.
<meta http-equiv="Page-Enter" content= "progid: DXImageTransform.Microsoft.Fade(Duration=2.3)">
<meta http-equiv="Page-Exit" content= "progid: DXImageTransform.Microsoft.Fade(Duration=2.3)">
Refreshes curent page every 5 seconds.
<meta http-equiv="refresh" content="5">
Redirects a page to a new address and Loads the new address after 5 seconds.
<meta http-equiv="refresh" content="5;URL= http://www.newAddress.com">
This is one method of setting a "cookie" in the user's Web browser. If you use an expiration date, the cookie is considered permanent and will be saved to disk (until it expires), otherwise it will be considered valid only for the current session and will be erased upon closing the Web browser.
<meta http-equiv="Set-Cookie" content="cookievalue= xxx;expires=Wednesday, 21-Oct-98 16:14:21 GMT; path=/">
<meta http-equiv="Content-Style-Type" content="text/css">
<meta http-equiv="content-script-type" content="text/javascript">
<meta name="CODE_LANGUAGE" content="C#">
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