Microformats Wiki - User contributions [en]

rel-faq

2007-03-08T00:45:42Z

XrX: /* Is/Was VoteLinks a proper use of rel? */

<h1> "rel" attribute frequently asked questions </h1>

This document serves to answer and discuss frequently asked questions about the HTML4 "rel" and "rev" attributes, and their linktype values. Specifically this document explores a number of issues common to and exposed by the various [[microformats]] which extend the HTML4 rel attribute.

__TOC__

== Authors ==
* John Allsopp, [http://westciv.com Western Civilisation]
* [http://tantek.com Tantek Çelik], [http://technorati.com Technorati, Inc]
* [[User:AndyMabbett|Andy Mabbett]]

== FAQ ==

===What microformats use "rel"? ===
*[[rel-directory]]
*[[rel-license]]
*[[rel-nofollow]]
*[[rel-tag]]
*[[rel-payment]]
*[[vote-links]]
*[http://gmpg.org/xfn/ XFN]

=== What is the proper use of the 'rel' attribute? ===

First, you can use the [http://www.w3.org/TR/html4/types.html#type-links linktype] as specified in [http://www.w3.org/TR/html4/ HTML 4]. A well known example of this is rel="stylesheet". Second, you "can extend the rel attribute using a [http://www.w3.org/TR/html4/types.html#type-links profile"], but "[http://www.w3.org/TR/html4/types.html#idx-link_type-2 HTML doesn't specify/recommend a profile format]". XMDP can be used to formally define new rel values.

=== What does a rel value really mean? ===

The rel values in HTML follow a consistent pattern which at a minimum ''implies'' a deliberate design. rel describes the relationship of a hyperlink in terms of what the destination (href) is, to the source, or from the source's perspective. rel="stylesheet" is perhaps the easiest example to understand in this manner, because it is saying that this resource over there (indicated with the href) ''is'' a "stylesheet" for the current document. Similarly, rel="help" link states that the resource indicated by the href is "help" (e.g. a help file or FAQ) for the current document. All the rest of the values defined in HTML4 also follow this pattern of being a ''noun'' which labels the resource indicated by the href, from the perspective of the current document.

=== Then what does "rev" mean? ===

"rev" is the precise opposite (or "reverse") of the "rel" attribute. E.g. a rev="help" link indicates that ''the current document'' is "help" for the resource indicated by the href.

=== Is rel single or bi directional? ===

Though the HTML4 specification is not specific on this point, all the rel values in the HTML4 specification follow a very consistent pattern that indicate a specific directionality to the value of the rel attribute. The ''only'' exception to this is the value "alternate", which, is actually inherently symmetric, so rel="alternate" means pretty much the same thing as rev="alternate". I say pretty much because in theory (and in practice) one of a pair of alternates is likely to be more definitive, and thus one is more a primary resource, with the other being an alternative. In theory you could extend rel with a new value, e.g. "original" which could be used to point back the original version of a document. This could be used for example with translations, where translations of a document would point back to the original with rel="original".

=== Are "rel" attributes, and linktypes in general, just document to document? ===

The vast majority of the rel values defined in HTML4 are from a document to a document. rel="stylesheet" is a bit of an exception, as it from an HTML document to a style sheet, which is more like a set of styling rules and instructions than a "document" in the classical sense. Two notable exceptions are rel="copyright" and rel="bookmark" which describe the relationship from the current document to (potentially) only part of a document. The 'rev' attribute adds an interesting perspective on this question. Specifically, [http://www.w3.org/TR/html4/struct/links.html#rev-link 12.3.1 of HTML4] shows an example of two links one using rel and the other using rev which mean the same thing. Thus linktypes in general may be either from a whole document or part of a document to a whole document or a part of a document. For example, the RelTag specification introduces the rel="tag" value, and notes that it indicates a relation from a document or major portion thereof to a document. Finally, XFN probably stretches rel the farthest, as it uses rel to indicate a person to person relationship. This person to person scope was not introduced by XFN, but merely adopted. It was introduced by bloggers who have taken to linking to other bloggers by name and thus using people's blog URLs as proxies for people themselves.

=== Is/Was VoteLinks a proper use of rel? ===

No. The problem with using rel for VoteLinks is made apparent with the following example:

<pre><nowiki>
<a href="http://www2005.org" rel="vote-for">WWW2005 is a great conference</a>
</nowiki></pre>

Following the reasoning in the earlier answer to the question of what a rel value means, this link would mean:

The resource indicated by http://www2005.org is a "vote-for" the current document.

That clearly doesn't make any sense, and was certainly not the intent of VoteLinks. Ironically, the reverse makes a lot more sense:

The current document is a "vote-for" the resource indicated by http://www2005.org.

(The same issue applies to rel="nofollow")

And generalizing to the same cultural usage links as XFN:

The current document, as a proxy for the person who wrote it (e.g. the blogger whose blog it is),
is a vote-for the resource indicated by http://www2005.org.

Fortunately the "rev" attribute captures this "reverse" relationship semantic, and thus the above example should be written like this:

<pre><nowiki>
<a href="http://www2005.org" rev="vote-for">WWW2005 is a great conference</a>
</nowiki></pre>

And thus VoteLinks has been changed to use "rev" instead of "rel", in order to keep the well known and easily understandable "vote-for", "vote-abstain", and "vote-against" values.

=== Should 'rev' even be used ===

Given that the 'rev' attribute has been more often misused by authors than properly used ([http://code.google.com/webstats/2005-12/linkrels.html Google Code: Web Authoring Statistics: Link Relationships]) is it even a good idea to use rev at all?

The short answer is unfortunately "no". Use of "rev" SHOULD be avoided.

However, VoteLinks, is being grandfathered since it was such an early use. No future microformats should be developed that use 'rev'.

=== When a 'rel' value refers to a relationship to or from a page or document, is it referring to just the page, or the contents of the page, or both? ===

The consensus (and convention) is that such rel values are referring to the page itself including its immediate contents, but not for example to embedded contents of like images, objects, frames etc.

== See Also ==

* [[rel-directory]]
* [[rel-examples]]
* [[rel-license]]
* [[rel-payment]]
* [[rel-tag]], [[rel-tag-faq]]
* [[rel-design-pattern]]
* [[vote-links]]
* [http://gmpg.org/xfn/ XFN], [http://gmpg.org/xfn/faq XFN FAQ]

hcard-implementations

2007-02-27T23:03:43Z

XrX: /* New Implementations */

<h1>hCard Implementations</h1>

This page is an '''informative''' section of the [[hcard|hCard specification]].

The following implementations have been developed which either generate or parse [[hcard|hCards]]. If you have an hCard implementation, feel free to add it to the top of this list.

== New Implementations ==
*[http://rafaeloliveira.net/labs/hcard_creator.zip Wordpress hCard Creator] - I've made this simple plugin for wordpress. It adds the hCard Options submenu at Options menu, where you can create a simple hCard and put it on your blog using < ?php hcard_creator() ?> to show it. Also, it is possible to show an "export to vCard" link, which uses Brian Suda X2V. (Got send an e-mail to him regarding this)
*[http://wikidentity.com/ Wikidentity] - Wikidentity is a Flash client that shows you any hCards in a page you are browsing, and allows you to search for hCards that other users have helped index. You can also export hCards that you've discovered to use in a variety of applications, such as Address Book.
*[http://yedda.com Yedda] - Yedda provides hcard based identities on all of the people's profiles
*[http://www.alexa.com/site/devcorner/hcard Alexa hcard search]
*[http://leftlogic.com/info/articles/microformats_bookmarklet Microformats Bookmarklet] is a bookmarklet designed for Safari (works in Firefox and Camino) that overlays on the current page to allow users to import individual hCards or hCalendars. Written by Remy Sharp.
*[http://elbewerk.com/2006/09/vcardexplorer-02.shtml vCardExplorer 0.2] is a Mac OS X Application, that displays VCF-Files and extracts hCards from Websites written by Daniel Kagemann.
* [http://placenamehere.com/mf/nnwextract/ Extract Microformats] is a script for NetNewsWire that supports extracting hCard and hCalendar data in blog posts (via technorati service). Written by [[User:ChrisCasciano|Chris Casciano]]
* [http://allinthehead.com/hkit/ hKit] is an open source PHP 5 parsing library with support for hCard.
* [http://kitchen.technorati.com/search Technorati Microformats Search] indexes [[hcard|hCard]], [[hcalendar|hCalendar]], and [[hreview|hReview]] as [http://tantek.com/log/2006/05.html#d31t1802 announced by Tantek].
** list of pages with indexing Issues so they can be looked into as to why data is not being extracted
** suda.co.uk/contact
** multipack.co.uk
* [http://www.webstandards.org/action/dwtf/microformats/ Dreamweaver Extension suite] from the [http://webstandards.org/ Web Standards Project] enables the authoring of hCards from within Dreamweaver 8.
* [http://scooch.gr0w.com/ Scooch] is a slide show and presentation creator that generates a [[hCard]] for individual slide show authors and comment authors with a CSS button to parse and download via [http://suda.co.uk/projects/X2V/ X2V]. Also uses [[hReview]] for slide ratings and [[rel-tag]] for categories.
* [http://blog.codeeg.com/2006/03/20/flock-tails-flocktails/ Flocktails] - port of Tails extension for Flock 0.5.12 that looks for hCards, hCalendar, xFolk and hReview and tosses them into a handy topbar
*[http://opensource.reevoo.com/2006/03/08/release-uformats-12/ uformats] is a ruby library that can parse [[hCalendar]], [[hCard]], [[hReview]] and [[rel-tag]]
* [http://blog.codeeg.com/tails-firefox-extension-03/ Tails] is a Firefox Extension that will display the presence and details of microformats ([[hcard|hCard]], [[hcalendar|hCalendar]], [[hreview|hReview]], [[xfolk|xFolk]]) on a webpage. [https://addons.mozilla.org/firefox/2240/ Tails Export] is an extended version.
* [http://www.stripytshirt.co.uk/features/firefox/smartzilla Smartzilla is a Firefox Extension] that finds hCards on web pages and lets you add them to your addressbook.
* [http://placenamehere.com/TXP/pnh_mf/ pnh_mf] is a plugin for [http://textpattern.com/ Textpattern] that supports embedding hCard and other microformats in templates and blog posts. Written by [http://placenamehere.com/ Chris Casciano].
* There is [http://flickr.com/photos/factoryjoe/68755089/ evidence of built-in hCard support in the Konqueror browser]. Specifically, Konqueror 3.5, in KDE 3.5 (kubuntu Breezy w/ update).
* There is [http://tagcamp.org/index.cgi?ContactList evidence of a kwiki plugin for hCards]. Update: the [http://svn.kwiki.org/cwest/Kwiki-hCard/ hCard kwiki plugin svn repository]. See the [http://microwiki.caseywest.com/index.cgi?hCard documentation of the hCard kwiki plugin].
* [http://suda.co.uk/projects/X2V/ X2V] is a bookmarklet that parses hCard and produces a .vcf (vCard) stream. Note: needs to be updated as the spec is refined
* [http://www.stripytshirt.co.uk Duncan Walker] has built [http://www.stripytshirt.co.uk/features/firefox/smartzilla a Firefox extension] that gets hCard data from a webpage, uses Brian Suda's XSL (locally) to transform it to vcard format and opens the resulting .vcf file.
* [http://george.hotelling.net/90percent/ George] has written a [http://george.hotelling.net/90percent/geekery/greasemonkey_and_microformats.php Greasemonkey user script] that detects hCards and allows users to easily add them to their address book application. Relies on the X2V web service to do the conversion.
* [http://inside.glnetworks.de/ Martin Rehfeld] has updated the work of [http://blogmatrix.blogmatrix.com/ David Janes] and produced a [[Greasemonkey]] [http://inside.glnetworks.de/2006/06/05/microformats-have-arrived-in-firefox-15-greasemonkey-06/ script] that finds many microformat elements, including hCards, and [http://blog.davidjanes.com/mtarchives/2005_08.html#003379 provides a popup menu of actions]. The hCard to vCard conversion is done internally within the script. ''This will work with FireFox 1.5+/GreaseMonkey 0.6.4+ now.''
* [http://diveintomark.org/ Mark Pilgrim] has also written an [http://diveintomark.org/projects/greasemonkey/hcard/ hCard parser Greasemonkey user script]. It is self-contained and does not rely on the X2V web service.
* [http://www.oliverbrown.me.uk/2005/09/03/a-working-microformats-extension-to-simplexml/ Oliver Brown] has written an "extension" to [http://www.php.net/simplexml SimpleXML] that gives simple access to hCard information in PHP 5.
* [http://thedredge.org/ Andrew D. Hume] has built a system (Wordpress plugin?) for [http://thedredge.org/2005/06/using-hcards-in-your-blog/ using hCards in your blog] to represent people leaving comments on blog posts.
* The [http://tantek.com/microformats/hcard-creator.html hCard creator] is a very simple, yet illustrative, open source user interface / form / script which creates an hCard in real-time as you type in a set of contact information.
* [http://greenbytes.de/tech/webdav/rfc2629.xslt rfc2629.xslt] now attempts to generate hCard information ([http://ietf.org/rfc/rfc2629 RFC2629] is an XML format for authoring RFCs and Internet Drafts, see [http://greenbytes.de/tech/webdav/rfc2629xslt/rfc2629xslt.html example document])
* [http://tantek.com/microformats/buddylist2hcards.html iChat buddy list to hCards] - Open source AppleScript to automatically convert one's buddy list in the MacOSX iChat AIM client into a valid XHTML 1.0 Strict list of hCards.
* [http://dev.w3.org/cvsweb/2001/palmagent/ palmagent] is a collection of palmpilot and sidekick tools. It includes X2V derivatives xhtml2hcard.xsl and toICal.xsl plus some [http://dev.w3.org/cvsweb/2001/palmagent/hcardTest.html hcardTest] materials
* [http://www.openpsa.org/ OpenPsa 2.x] CRM application uses hCard for all person listings. The widget is [http://www.midgard-project.org/midcom-permalink-922834501b71daad856f35ec593c7a6d reusable across Midgard CMS]
* [http://www.metonymie.com Emiliano Martínez Luque] has written an experimental [http://www.metonymie.com/hCard_extract/app.html hCard finder and structured search application] that finds hCards within a given set of URLs and returns the ones that match the specified search criteria.

*[[https://addons.mozilla.org/firefox/4106/ Operator]] lets you combine pieces of information on Web sites with applications in ways that are useful. (Firefox-plugin)

== Additional Applications ==
This section is '''informative'''.

There are numerous potential additional uses and applications for hCards on the Web. The following are merely a few thoughts and possibilities that folks have come up with:

* As an open standard/format for [http://www.gravatar.com/ Gravatars].
* Marking up individual authors of blog posts on a group blog
* Marking up people's names and URLs in a blogroll
* Any reference to people in blog posts (e.g. when citing them, or referencing them, or describing them, by name).
* ...

== Related Pages ==
{{hcard-related-pages}}

hcard-implementations

2007-02-27T23:02:15Z

XrX: /* New Implementations */ + Operator - Microformat Base (down)

<h1>hCard Implementations</h1>

This page is an '''informative''' section of the [[hcard|hCard specification]].

The following implementations have been developed which either generate or parse [[hcard|hCards]]. If you have an hCard implementation, feel free to add it to the top of this list.

== New Implementations ==
*[http://rafaeloliveira.net/labs/hcard_creator.zip Wordpress hCard Creator] - I've made this simple plugin for wordpress. It adds the hCard Options submenu at Options menu, where you can create a simple hCard and put it on your blog using < ?php hcard_creator() ?> to show it. Also, it is possible to show an "export to vCard" link, which uses Brian Suda X2V. (Got send an e-mail to him regarding this)
*[http://wikidentity.com/ Wikidentity] - Wikidentity is a Flash client that shows you any hCards in a page you are browsing, and allows you to search for hCards that other users have helped index. You can also export hCards that you've discovered to use in a variety of applications, such as Address Book.
*[http://yedda.com Yedda] - Yedda provides hcard based identities on all of the people's profiles
*[http://www.alexa.com/site/devcorner/hcard Alexa hcard search]
*[http://leftlogic.com/info/articles/microformats_bookmarklet Microformats Bookmarklet] is a bookmarklet designed for Safari (works in Firefox and Camino) that overlays on the current page to allow users to import individual hCards or hCalendars. Written by Remy Sharp.
*[http://elbewerk.com/2006/09/vcardexplorer-02.shtml vCardExplorer 0.2] is a Mac OS X Application, that displays VCF-Files and extracts hCards from Websites written by Daniel Kagemann.
* [http://placenamehere.com/mf/nnwextract/ Extract Microformats] is a script for NetNewsWire that supports extracting hCard and hCalendar data in blog posts (via technorati service). Written by [[User:ChrisCasciano|Chris Casciano]]
* [http://allinthehead.com/hkit/ hKit] is an open source PHP 5 parsing library with support for hCard.
* [http://kitchen.technorati.com/search Technorati Microformats Search] indexes [[hcard|hCard]], [[hcalendar|hCalendar]], and [[hreview|hReview]] as [http://tantek.com/log/2006/05.html#d31t1802 announced by Tantek].
** list of pages with indexing Issues so they can be looked into as to why data is not being extracted
** suda.co.uk/contact
** multipack.co.uk
* [http://www.webstandards.org/action/dwtf/microformats/ Dreamweaver Extension suite] from the [http://webstandards.org/ Web Standards Project] enables the authoring of hCards from within Dreamweaver 8.
* [http://scooch.gr0w.com/ Scooch] is a slide show and presentation creator that generates a [[hCard]] for individual slide show authors and comment authors with a CSS button to parse and download via [http://suda.co.uk/projects/X2V/ X2V]. Also uses [[hReview]] for slide ratings and [[rel-tag]] for categories.
* [http://blog.codeeg.com/2006/03/20/flock-tails-flocktails/ Flocktails] - port of Tails extension for Flock 0.5.12 that looks for hCards, hCalendar, xFolk and hReview and tosses them into a handy topbar
*[http://opensource.reevoo.com/2006/03/08/release-uformats-12/ uformats] is a ruby library that can parse [[hCalendar]], [[hCard]], [[hReview]] and [[rel-tag]]
* [http://blog.codeeg.com/tails-firefox-extension-03/ Tails] is a Firefox Extension that will display the presence and details of microformats ([[hcard|hCard]], [[hcalendar|hCalendar]], [[hreview|hReview]], [[xfolk|xFolk]]) on a webpage. [https://addons.mozilla.org/firefox/2240/ Tails Export] is an extended version.
* [http://www.stripytshirt.co.uk/features/firefox/smartzilla Smartzilla is a Firefox Extension] that finds hCards on web pages and lets you add them to your addressbook.
* [http://placenamehere.com/TXP/pnh_mf/ pnh_mf] is a plugin for [http://textpattern.com/ Textpattern] that supports embedding hCard and other microformats in templates and blog posts. Written by [http://placenamehere.com/ Chris Casciano].
* There is [http://flickr.com/photos/factoryjoe/68755089/ evidence of built-in hCard support in the Konqueror browser]. Specifically, Konqueror 3.5, in KDE 3.5 (kubuntu Breezy w/ update).
* There is [http://tagcamp.org/index.cgi?ContactList evidence of a kwiki plugin for hCards]. Update: the [http://svn.kwiki.org/cwest/Kwiki-hCard/ hCard kwiki plugin svn repository]. See the [http://microwiki.caseywest.com/index.cgi?hCard documentation of the hCard kwiki plugin].
* [http://suda.co.uk/projects/X2V/ X2V] is a bookmarklet that parses hCard and produces a .vcf (vCard) stream. Note: needs to be updated as the spec is refined
* [http://www.stripytshirt.co.uk Duncan Walker] has built [http://www.stripytshirt.co.uk/features/firefox/smartzilla a Firefox extension] that gets hCard data from a webpage, uses Brian Suda's XSL (locally) to transform it to vcard format and opens the resulting .vcf file.
* [http://george.hotelling.net/90percent/ George] has written a [http://george.hotelling.net/90percent/geekery/greasemonkey_and_microformats.php Greasemonkey user script] that detects hCards and allows users to easily add them to their address book application. Relies on the X2V web service to do the conversion.
* [http://inside.glnetworks.de/ Martin Rehfeld] has updated the work of [http://blogmatrix.blogmatrix.com/ David Janes] and produced a [[Greasemonkey]] [http://inside.glnetworks.de/2006/06/05/microformats-have-arrived-in-firefox-15-greasemonkey-06/ script] that finds many microformat elements, including hCards, and [http://blog.davidjanes.com/mtarchives/2005_08.html#003379 provides a popup menu of actions]. The hCard to vCard conversion is done internally within the script. ''This will work with FireFox 1.5+/GreaseMonkey 0.6.4+ now.''
* [http://diveintomark.org/ Mark Pilgrim] has also written an [http://diveintomark.org/projects/greasemonkey/hcard/ hCard parser Greasemonkey user script]. It is self-contained and does not rely on the X2V web service.
* [http://www.oliverbrown.me.uk/2005/09/03/a-working-microformats-extension-to-simplexml/ Oliver Brown] has written an "extension" to [http://www.php.net/simplexml SimpleXML] that gives simple access to hCard information in PHP 5.
* [http://thedredge.org/ Andrew D. Hume] has built a system (Wordpress plugin?) for [http://thedredge.org/2005/06/using-hcards-in-your-blog/ using hCards in your blog] to represent people leaving comments on blog posts.
* The [http://tantek.com/microformats/hcard-creator.html hCard creator] is a very simple, yet illustrative, open source user interface / form / script which creates an hCard in real-time as you type in a set of contact information.
* [http://greenbytes.de/tech/webdav/rfc2629.xslt rfc2629.xslt] now attempts to generate hCard information ([http://ietf.org/rfc/rfc2629 RFC2629] is an XML format for authoring RFCs and Internet Drafts, see [http://greenbytes.de/tech/webdav/rfc2629xslt/rfc2629xslt.html example document])
* [http://tantek.com/microformats/buddylist2hcards.html iChat buddy list to hCards] - Open source AppleScript to automatically convert one's buddy list in the MacOSX iChat AIM client into a valid XHTML 1.0 Strict list of hCards.
* [http://dev.w3.org/cvsweb/2001/palmagent/ palmagent] is a collection of palmpilot and sidekick tools. It includes X2V derivatives xhtml2hcard.xsl and toICal.xsl plus some [http://dev.w3.org/cvsweb/2001/palmagent/hcardTest.html hcardTest] materials
* [http://www.openpsa.org/ OpenPsa 2.x] CRM application uses hCard for all person listings. The widget is [http://www.midgard-project.org/midcom-permalink-922834501b71daad856f35ec593c7a6d reusable across Midgard CMS]
* [http://www.metonymie.com Emiliano Martínez Luque] has written an experimental [http://www.metonymie.com/hCard_extract/app.html hCard finder and structured search application] that finds hCards within a given set of URLs and returns the ones that match the specified search criteria.

*[[https://addons.mozilla.org/firefox/4106/|Operator]] lets you combine pieces of information on Web sites with applications in ways that are useful. (Firefox-plugin)

== Additional Applications ==
This section is '''informative'''.

There are numerous potential additional uses and applications for hCards on the Web. The following are merely a few thoughts and possibilities that folks have come up with:

* As an open standard/format for [http://www.gravatar.com/ Gravatars].
* Marking up individual authors of blog posts on a group blog
* Marking up people's names and URLs in a blogroll
* Any reference to people in blog posts (e.g. when citing them, or referencing them, or describing them, by name).
* ...

== Related Pages ==
{{hcard-related-pages}}