XHTML Document Header Resource

This XHTML header tags resource is a work in progress, perpetually expanding and evolving as new information is obtained, explored, and integrated. Hopefully, you will find it useful in some way. Even better, perhaps you will share any complimentary or critical information concerning the contents of this article.

Table of Contents


Important Information [ ^ ]

This article presents information as concisely as possible, and is intended as a general overview of XHTML header tags. More detailed header tag information is available elsewhere. In this article, each tag is presented along with a brief definition or explanation. Where two (or more) tag examples are provided, the first is a generalized version while others represent specific situations.

It is important to note that, when writing XHTML code, all tags (e.g., meta, link, head) and their corresponding attributes (e.g., href, rel, content) must be expressed entirely in lowercase character. However, the values of tag attributes are entirely case-insensitive. Also, valid XHTML also requires all tag elements to be closed. Thus, remember to close elements such as link, base, and meta with a "space-slash-bracket" (" />").


XML Declaration (Prolog) [ ^ ]

The XML Declaration, or prolog, is used in conjuction with XHTML and is not required for HTML documents. As XML documents, pages structured via XHTML should begin with an XML declaration:

<?xml version="1.0" encoding="windows-1250"?>

Note: documents using UTF-8 character encoding (default) do not need to use this declaration. Omission of the XML declaration is useful to prevent Internet Explorer from switching to “quirks mode.”

XHTML/HTML !DOCTYPE [ ^ ]

This tag, used in conjunction with http-equiv content-type, provides complete document content information, equipping modern browsing devices to correctly interpret document contents. Check out this article for a more complete collection of conforming, bare-bones document templates.

HTML 4.01 !DOCTYPE

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "http://www.w3.org/TR/html4/frameset.dtd">

XHTML 1.0 !DOCTYPE

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">


The html tag [ ^ ]

The html tag encloses all subsequent tags. The html tag may include various attributes, including one declaring any XML Name Space (xmlns), and another declaring various other XML properties (xml:property="value").

Use this for HTML:

<html></html>

Use this for XHTML 1.0 and 1.1:

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"></html>

And use this for XHTML 2.0:

<html xmlns="http://www.w3.org/2002/06/xhtml2"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.w3.org/2002/06/xhtml2 TBD"
     xml:lang="en"></html>


The head tag [ ^ ]

The head tag encloses much of the documents “meta” information, and may include the following tags: <code>, <base>, <link>, <meta>, <script>, <style>, <title>. There are several attributes that may be included in the head tag, as shown in the following examples:

<head dir="ltr | rtl" id="unique alphanumeric identifier" lang="language code" profile="url"></head>
<head dir="ltr" id="head-id" lang="EN" profile="http://gmpg.org/xfn/11"></head>


The title tag [ ^ ]

The title tag is a crucial part of any web document. An effective title may help the search ranking of the document. We all know this one:

<title>The Document Title< /title>


base & item [ ^ ]

The base tag indicates a predefined target base for all relative links provided on the page (related tag: http-equiv window-target). Using the base tag ensures relative links reach their targets even if the structure of the site directory changes. Further, the base tag is a great way to save bandwidth and simplify code by writing long URLs, parameterized URLs, and other unsightly URLs only once and out of view. Perhaps the most underrated of all tags. Here are two examples; the first defines an external target while the second instructs all links to open in a new window:

<base href="http://www.domain.com/index.html"/>
<base target="_blank"/>

[ Note: for more information on available target attribute values, check out our delightful article, The Friendliest Link Targets in the Neighborhood. ]

The item tag defines specific objects referenced in the document:

<item label="label" url="http://www.domain.com/"/></item>


http-equiv [ ^ ]

http-equiv tags send the browser information involving the actual processing of the web document itself. http-equiv tags effectively function in the same way as HTTP headers sent directly by the server, and are responsible for specifying actions related to content caching, location redirection, and page refreshing. The term “http-equiv” indicates its equivalence with HTTP headers, which are frequently generated from HTML tags such as http-equiv.

http-equiv window-target

The http-equiv window-target tag indicates a predefined target base for all relative links provided on the page (related tag: base). Using the http-equiv window-target tag ensures relative links reach their targets even if the structure of the site directory changes. Further, the base tag is a great way to save bandwidth and simplify code by writing long URLs, parameterized URLs, and other unsightly URLs only once and out of view. Here are examples showing some popular instances of the http-equiv window-target tag:

<meta http-equiv="window-target" content="../../relative/directory/"/>
<meta http-equiv="window-target" content="http://external-domain.com/dir/"/>

<meta http-equiv="window-target" content="_top"/>
<meta http-equiv="window-target" content="_parent"/>
<meta http-equiv="window-target" content="_blank"/>
<meta http-equiv="window-target" content="_none"/>

[ Note: for more information on available target attribute values, check out our delightful article, The Friendliest Link Targets in the Neighborhood. ]

http-equiv content-style-type & content-script-type

The http-equiv content-style-type &amp; content-script-type tags indicate document style and script types, respectively, thereby permitting their omission from corresponding tags> For example, inclusion of the http-equiv content-style-type tag with a content value of text/css permits the document authors to omit this information when writing all subsequent < style> tags.

<meta http-equiv="content-style-type" content="text/css"/>
<meta http-equiv="content-script-type" content="text/javascript"/>

http-equiv content-type

The content-type tag specifies the document content type and corresponding character set. Examples of character type include UTF-8, ISO-8859-1, ISO-2022-JP. This tag instructs Netscape Navigator to load the appropriate character set before displaying the document contents. This tag should always be used in conjuction with the DTD declaration within the !DOCTYPE statement. Providing both DTD and http-equiv content-type ensures correct character interpretation and display.

<meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
<meta http-equiv="content-type" content="text/html; charset=US-ASCII"/>
<meta http-equiv="content-type" content="text/html; charset=ISO-8859-1"/>

Here is a (partial) list of character sets (charsets) commonly used to encode XHTML documents:

  • utf-8
  • utf-16
  • iso-8859-1
  • windows-1250
  • iso-8859-2

http-equiv content-language

The http-equiv content-language tag specifies the language used in the document. All supported languages are RFC-1766 compliant. Some supported languages include: BG (Bulgarian), CS (Czech), DA (Danish), DE (German), EL (Greek), EN (English), EN-GB (English-Great Britain), EN-US (English-United States), ES (Spanish), ES-ES (Spanish-Spain), FI (Finnish), HR (Croatian), IT (Italian), FR (French), FR-CA (French-Quebec), FR-FR (French-France), IT (Italian), JA (Japanese), KO (Korean), NL (Dutch), NO (Norwegian), PL (Polish), PT (Portuguese), RU (Russian), SV (Swedish), ZH (Chinese).

<meta http-equiv="content-language" content="EN"/>

http-equiv pragma & cache-control

The http-equiv pragma & cache-control tags are used together to control document caching and archiving. There are several methods of controlling how search engines and other clients crawl site content. If possible, use a robots.txt or htaccess file to accomplish caching directives. If it is not possible or preferable to use either of these files, the http-equiv pragma &amp; cache-control tags are preferred over the popular meta robots tag, as their caching influence is more universally affectual. Possible content values include: public (content may be cached in public shared caches), private (content may only be cached in private cache), no-cache (content may not be cached), and no-store (content may be cached but not archived).

<meta http-equiv="pragma" content="no-cache"/>
<meta http-equiv="cache-control" content="no-cache"/>

http-equiv reply-to

The http-equiv reply-to tag specifies contact information (related tag: meta reply-to):

<meta http-equiv="reply-to" content="spam@spamcity.com"/>

http-equiv refresh

The http-equiv refresh tag is used to redirect or refresh the document, but is no longer recommended because of the exclusion rules of several major search engines. The preferable method for URL redirection is via htaccess and mod_rewrite4. The content value, “x” in our example, determines the amount of time in seconds before which the browser will be redirected or refreshed according to the specified URL (related tag: meta refresh).

<meta http-equiv="refresh" content="x; url=http://www.domain.com/doc.html"/>

http-equiv set-cookie

The http-equiv set-cookie tag creates a persistent cookie according to specified attributes, which include: value (the name of the cookie), n (the value of the cookie), date (the date/time of expiry), and url (the associated cookie path, if any). When the expiry date value is null, the cookie is deleted after the current session. The expiry date should be expressed in RFC850 format.

<meta http-equiv="Set-Cookie" content="value=n; expires=date; path=url"/>
<meta http-equiv="Set-Cookie" content="pie=3.14159265358979; expires=Monday, 04-July-50 07:07:07 GMT; path=./path/"/>

http-equiv expires

The http-equiv expires tag specifies an expiry date/time for the document. All date/time stamps must be generated in Greenwich Mean Time5 (GMT) and in RFC 1123 format. For more information on GMT formatting, check out our article, Greenwich Mean Time (GMT) Formats. Related tag: meta expires.

<meta http-equiv="expires" content="Mon, 04 Jul 2050 07:07:07 GMT" />

http-equiv page-enter

The http-equiv page-enter tag instructs compatible browsers to apply the specified transition to your page upon entering. Set the Duration value to the amount of time over which the transition should occur. Set the Transition value to the corresponding transitional effect (see below). Note that this trick will not work with frames.

<meta http-equiv="page-enter" content="RevealTrans(Duration=second;Transition=n)"/>

http-equiv page-exit

The http-equiv page-exit tag instructs compatible browsers to apply the specified transition to your page upon page exit. Set the Duration value to the amount of time over which the transition should occur. Set the Transition value to the corresponding transitional effect (see below). Note that this trick will not work with frames.

<meta http-equiv="page-exit" content="RevealTrans(Duration=second;Transition=n)"/>

Here is a list of transition numbers and their corresponding transitional effects:

  • 0 – Box in
  • 1 – Box out
  • 2 – Circle in
  • 3 – Circle out
  • 4 – Wipe up
  • 5 – Wipe down
  • 6 – Wipe right
  • 7 – Wipe left
  • 8 – Vertical blinds
  • 9 – Horizontal blinds
  • 10 – Checkerboard across
  • 11 – Checkerboard down
  • 12 – Random dissolve
  • 13 – Split vertical in
  • 14 – Split vertical out
  • 15 – Split horizontal in
  • 16 – Split horizontal out
  • 17 – Strips left down
  • 18 – Strips left up
  • 19 – Strips right down
  • 20 – Strips right up
  • 21 – Random bars horizontal
  • 22 – Random bars vertical
  • 23 – Random

miscellaneous http-equiv attributes

<meta http-equiv="imagetoolbar" content="no" />

<meta http-equiv="MsThemeCompatible" content="no" />


link next

The link next tag specifies the URL of the next document (in a series of documents) that the agent/browser should load:

<link rel="next" href="[Next URL in series]"/>

link prev

The link prev tag specifies the URL of the previous document in a series of documents:

<link rel="prev" href="[Previous URL in series]"/>

link prefetch

The link prefetch tag specifies a URL which should preload:

<link rel="prefetch" href="[URL to preload]"/>

link stylesheet

The link stylesheet tag is used to associate an external .CSS file with the document. When using the link stylesheet tag it is necessary to include both type="text/css" and media="value", where “value” is set to either “print”, “screen”, or “all”:

<link rel="stylesheet" href="/css/print.css" type="text/css" media="print"/>
<link rel="stylesheet" href="/css/screen.css" type="text/css" media="screen"/>
<link rel="stylesheet" href="/css/mains.css" type="text/css" media="all"/>

link shortcut icon

The link shortcut icon tag is used to associate a favicon.ico file to the document. In addition the link shortcut icon tag, the link icon tag also links a site to its associated favicon. Often, documents employ both of the following links tags (with identical directory paths) simultaneously:

<link rel="shortcut icon" href="favicon.ico" type="image/x-icon"/>
<link rel="icon" href="http://domain.com/favicon.ico" type="image/x-icon"/>
<link rel="icon" href="http://domain.com/favicon.png" type="image/png"/>

link alternate

The link alternate tag may be used for establishing any number of a variety of link types. This tag is frequently associated with syndicated content, their inclusion subsequently enabling modern browsers to “autodiscover” any feeds that may be offered. For WordPress users, there is now a plugin that automatically produces a user-specified set of feed links 2. For this tag, the type attribute defines the feed format, while the title attribute specifies the title given to the feed. Here are several examples of the link alternate tag providing feed links:

<link rel="alternate" type="application/rss+xml" title="RSS 2.0 Feed" href="http://www.domain.com/RSS"/>
<link rel="alternate" type="application/atom+xml" title="Atom Feed" href="http://www.domain.com/Atom"/>
<link rel="alternate" type="text/xml" title="RSS 0.92 Feed" href="http://www.domain.com/feed"/>

link pingback

The link pingback tag enables pingbacks by associating required function(s) via the hypertext reference attribute (href):

<link rel="pingback" href="http://www.domain.com/xmlrpc.php"/>

link archives

The link archives tag is used to associate a set of archive links to specified documents:

<link rel="archives" title="Archive Title" href="http://www.domain.com/archive/2002"/>

link bookmark

The bookmark tag specifies a “key entry point within an extended document.” For example, the following bookmark links employ title attributes to specify associated names for each of the bookmarks. Each web document may include multiple bookmark links.

<link rel="bookmark" type="text/html" href="http://domain.tld/current-doc.php#bookmark-01" title="Title of First Bookmark"/>
<link rel="bookmark" type="text/html" href="http://domain.tld/current-doc.php#bookmark-02" title="Title of Second Bookmark"/>
<link rel="bookmark" type="text/html" href="http://domain.tld/current-doc.php#bookmark-03" title="Title of Third Bookmark"/>

a few more..

Here are a few more that should be relatively (ha ha) self-explanatory:

<link rel="contents" href="http://domain.tld/main/" title="Main Contents"/>
<link rel="start" href="http://domain.tld/intro/" title="Introduction Page"/>
<link rel="help" href="http://domain.tld/faq/" title="Frequently Asked Questions"/>
<link rel="copyright" href="http://domain.tld/copyright/" title="Copyright Statement"/>
<link rel="license" href="http://domain.tld/license/" title="License Information"/>
<link rel="top" type="text/html" href="http://domain.tld/"/>
<link rel="parent" type="text/html" href="http://domain.tld/"/>
<link rel="author" href="mailto:spam@spamcity.com"/>
<link rel="contents" type="text/html" href="http://domain.tld/sitemap.html"/>
<link rel="index" type="text/html" href="http://domain.tld/related-index.html"/>
<link rel="glossary" type="text/html" href="http://domain.tld/related-glossary.html"/>
<link rel="chapter" type="text/html" href="http://domain.tld/chapter-of-series.html"/>
<link rel="section" type="text/html" href="http://domain.tld/section-of-series.html"/>
<link rel="subsection" type="text/html" href="http://domain.tld/subsection-of-series.html"/>
<link rel="appendix" type="text/html" href="http://domain.tld/related-appendix.html"/>

Beyond the link types defined in this article, authors may create customized link types by defining them in an associated profile. For more information, refer to the profile attribute in the head element of this document (view source code).


meta tags [ ^ ]

Each meta element provides metadata according to its pair of name and content attributes. For each meta element, name specifies the property and content defines its property. All meta tags are entirely case-insensitive. If you are using XHTML for markup, however, all tags must be lowercase, but their values are case-insensitive. WordPress users may now add a complete set of meta data by using our free plugin, Head MetaData Plus 3.

meta title

Although the meta title tag is no longer used by most major search engines, it remains useful for reference and organizational purposes. This tag is simialr to the title tag, which should be used either in addition to or as replacement for the meta title tag:

<meta name="title" content="This is the Title of the Page"/>

meta description

The meta description tag is used in the search results of major search engines. Optimizing the content of this tag with effective keywords will help improve page rank. Use any alphanumeric characters — uppercase and/or lowercase — and limit to 250 characters (including spaces) or less:

<meta name="description" content="This is the description of the page."/>

meta keywords

Also important in search engine optimization, meta keywords are used by search engines in determining the type of content contained in the document. To optimize this tag, limit the number of keywords to around 12 page-specific lowercase words or short phrases. The keywords may be space-seperated or comma-seperated:

<meta name="keywords" content="keywords, buzzwords, descriptive, optimized, spelling, variations, etcetera"/>

meta language

The meta language tag indicates the language used in the document (related tag: http-equiv language):

<meta name="language" content="English"/>

meta subject

The meta subject tag indicates the primary subject of the document. Although the meta subject tag is no longer used by most major search engines, it remains useful for reference and organizational purposes:

<meta name="subject" content="The Subject of the Page"/>

meta abstract

The meta abstract tag provides a brief description of the document, and is usually a summary of the description tag:

<meta name="abstract" content="This is a brief yet descriptive summary of the page content."/>

meta generator

The meta generator tag specifies the generator or software used in the production of the document:

<meta name="generator" content="The Generator of the Document"/>

meta publisher

The meta publisher tag specifies the publisher of the document:

<meta name="publisher" content="Document Publisher"/>

meta owner

The meta owner tag specifies the owner of the document:

<meta name="owner" content="Document Owner"/>

meta copyright

The meta copyright tag specifies copyright information and/or trademark names, patent numbers, or other legal information:

<meta name="copyright" content="The Business, 2008. All rights Reserved."/>

meta date

The meta date tag specifies the date on which the document was last modified:

<meta name="date" content="YYYY-MM-DDThh:mm:ssTZD" />

  • YYYY = four-digit year
  • MM = two-digit month
  • DD = two-digit day of month
  • hh = two-digit hour (00 through 23 only)
  • mm = two-digit minute (00 through 59)
  • ss = two-digit second (00 through 59)
  • TZD = time zone designator

meta address

The meta address tag specifies an associated contact address for the document:

<meta name="address" content="contact address info" />

meta author

The meta author tag specifies the author(s) of the document, and may include name(s), email(s), and/or url(s). Note, the preferred language of the author should be specified via the lang="xx" attribute, where xx represents the two-digit language abbreviation.

<meta name="author" content="Author Name, spam-please@tons-of-spam.com"/>

meta designer

The meta designer tag specifies the designer(s) of the document:

<meta name="designer" content="The Designer"/>

meta template

The meta template tag indicates the name of any template pertaining to the document:

<meta name="template" content="Template Name"/>

meta resource-type

The meta resource-type tag describes the document resource type, and should be used in conjuction with the DTD declaration. Apparently, the value for the content attribute must always be document:

<meta name="resource-type" content="document"/>

meta classification

The meta classification tag describes the document’s classification:

<meta name="classification" content="Website Design"/>

meta doc-type, doc-class, & doc-rights

Here are three additional tags that may be used to help further define, classify and/or organize documents:

<meta name="doc-type" content="public"/>
<meta name="doc-class" content="completed"/>
<meta name="doc-rights" content="copywritten work"/>

meta distribution

The meta distribution tag defines the intended level of distribution of the document on the world wide web. Supported distribution types include global (WWWeb), local (IP Block), and IU (Internal Use: not recommended, may cause problems). Use of this tag is rare for documents that are intended for use throughout the entire World Wide Web. Documents using this tag to limit distribution are advised to use the robots.txt or htaccess file either in addition to or as replacement for the meta distribution tag.

<meta name="distribution" content="global"/>

meta page-topic

The meta page-topic tag describes the topic of the document:

<meta name="page-topic" content="Topic of the Page"/>

meta page-type

The meta page-type tag enables authors to further specify and/or classify the page by indicating a specific type:

<meta name="page-type" content="Commercial"/>

meta audience

The meta audience tag specifies a specific audience type:

<meta name="audience" content="All"/>

meta rating

The meta rating tag specifies the rating of the document within the context of intended audience type:

<meta name="rating" content="general"/>

meta robots

The meta robots tag declares to search engines which links and/or content to follow/ignore, cache/archive, and/or display/ignore. Although the robots.txt1 file is the preferred method for these directives, the meta robots tag issues the same directives, namely all, index, noindex, follow, nofollow, as well as noimageindex and nomediaindex (related tag: http-equiv cache-control):

<meta name="robots" content="index,follow"/>

Here are the possible values for the meta robots tag:

  • index – index the page
  • noindex – don’t index the page
  • follow – follow links from the page
  • nofollow – don’t follow links from the page
  • noarchive – don’t cache/archive the page
  • none – do nothing, ignore the page
  • all – do whatever you want, default behavior

meta googlebot

The meta googlebot tag declares to search engines which links and/or content to follow/ignore, cache/archive, and/or display/ignore. Although the robots.txt1 file is the preferred method for these directives, the meta googlebot tag issues the same directives, namely all (open season on all content), index (index pages for search results), noindex (do not index pages for search results), follow (follow links), nofollow (do not follow links), archive (please archive/cache all content), noarchive (do not cache/archive content), snippet (use cached content as search result excerpt), nosnippet (use no excerpt or cached content in search results — use title tag instead):

<meta name="googlebot" content="noarchive"/>

meta refresh

The meta refresh tag instructs the browser to refresh the document after the specified number of seconds (related tag: http-equiv refresh):

<meta name="refresh" content="5"/>

meta expires

The meta expires tag is used in conjuction with the meta revisit-after tag for frequently updated content. The meta expires tag indicates the expiry date for the document (related tag: http-equiv expires). This tag requires RFC1123 date format:

<meta name="expires" content="Mon, 04 Jul 2050 07:07:07 GMT"/>

<meta name="expires" content="Never"/>

meta revisit-after

The revisit-after tag declares the number of days after which search engines should revisit your webpage for re-indexing. This tag is used in conjuction with the meta expires tag for frequently updated content. The revisit-after tag is useful for search rank optimization when search results are ordered according to date of most recent submission:

<meta name="revisit-after" content="3"/>

meta reply-to

The meta reply-to tag specifies contact information (related tag: http-equiv reply-to):

<meta name="reply-to" content="Some Person, somebody@somewhere.com"/>

meta no-email-collection

The meta no-email-collection tag instructs search agents not to collect any email addresses from the document. Further, a link may provided to any specific email policy regarded by the domain. Note: although some search engines may indeed obey this command, many do not.

<meta name="no-email-collection" value="http://www.domain.com/policy.html"/>

meta VW96.ObjectType

The meta VW96.ObjectType tag is based on an early version of the Dublin Core report, using a defined schema of document types:

<meta name="VW96.ObjectType" content="faq | howto |etc"/>

meta MSSmartTags

The meta MSSmartTags tag has something to do with Microsoft software and, well I really don’t (yawn) care enough to research this tag:

<meta name="MSSmartTags" content="true"/>
<meta name="MSSmartTagsPreventParsing" content="true"/>

Other proprietary Microsoft nonsense

These are listed here for reference purposes only. If you find yourself needing more information regarding these proprietary tags, you are in a dark place, traveling down a very dark road..

<meta name="DownloadOptions" content="Download Options for Whatever"/>
<meta name="ProgId" content="Programmatic Identifier for Whatever"/>
<meta name="Template" content="Template Location for the Document"/>

Here is one for the MSIE image toolbar. Useful for disabling such nonsense:

<meta http-equiv="imagetoolbar" content="yes|no|true|false"/>

This one is used to disable the MS WinXP theme compatibility nonsense:

<meta http-equiv="MSThemeCompatible" content="no"/>

meta version

Indicate any specific content version info via this tag:

<meta name="version" content="MeatSpace 3.0"/>

meta presdate

Indicate any specific content presentation date via this tag: (date shown represents 2007/01/01)

<meta name="presdate" content="20070101"/>

meta defaultView

Indicate any specific content view type via this tag:

<meta name="defaultView" content="slideshow"/>

meta controlVis

Indicate the visibilty status of any inherent controls for the document:

<meta name="controlVis" content="hidden"/>

meta viewport

This tag is recognized by the iPhone’s Mobile Safari browser and controls the behavior of its viewport. For example, if your site is 777 pixels wide, using the following meta tag would enable Mobile Safari to size the viewport according to the correct dimensions:

<meta name="viewport" content="width=777" />

miscellaneous meta attributes

<meta name="autosize" content="off"/>


geo meta tags [ ^ ]

The meta geo tag specifies the relative physical location of the document. For the geo.position name, latitude is plotted vertically as the “y” coordinate, while longitude is plotted horizontally as the “x” coordinate. For more information, search for “geotag generator” and “checkmap” or “check map” Web pages that utilize the geo.position tag are encouraged to display a GeoTag icon (404 link removed 2013/02/04):

<meta name="geo.position" content="latitude;longitude"/>
<meta name="geo.position" content="49.2;-123.4"/>

The geo.placename helps to further define physical location by specifying the name of the location:

<meta name="geo.placename" content="place name"/>
<meta name="geo.placename" content="London, Ontario"/>

There is also a geo.region tag that is useful for indicating the associated region via the country’s subdivision code. The country’s subdivion code is predefined, taken from a controlled ISO 3166-2 list, and may be used for resource discovery. If the regional code is unknown, the 2-character country code may be used instead. This tag may also be used to check or validate the geo.position tag:

<meta name="geo.region" content="country subdivision code"/>
<meta name="geo.region" content="US-WA"/>

And don’t forget about the "geo.country" meta tag, which indicates the two-digit abbreviation of the associated country:

<meta name="geo.country" content="US"/>

Here is another set of tags used to add your location to the GeoURL ICBM Address Server
more info (404 link removed 2013/04/02):

<meta name="ICBM" content="XXX.XXXXX, XXX.XXXXX"/>
<meta name="DC.title" content="THE NAME OF YOUR SITE"/>

Dublin Core tags [ ^ ]

The Dublin Core Metadata Initiative (DCMI) is an organization dedicated to promoting the widespread adoption of interoperable metadata standards and developing specialized metadata vocabularies for describing resources that enable more intelligent information discovery systems.

Here are a few of the metadata elements developed by the Dublin Core; for a complete list, check out their website at http://dublincore.org/.

<meta name="dc.title" content="Document Title"/>
<meta name="dc.format" content="Document Format"/>
<meta name="dc.rights" content="Document Rights"/>

References & Related