Lim Chee Aun

Tags and folksonomy

These few days, I've added some tags links for my link roll section on the sidebar. Using Magpie, the del.icio.us's RSS feed is parsed and displayed as HTML output. At first, the output is coded as such:

<ul>
<li><a href="hyperlink" title="description">title</a></li>
...
</ul>

Later, I read the del.icio.us's RSS feed and found that it also contains the tags for each feed item, for example:

<item rdf:about="http://www.mezzoblue.com/archives/2005/05/13/columns_grid/">
<title>Columns &amp; Grids</title>
<link>http://www.mezzoblue.com/archives/2005/05/13/columns_grid/</link>
<description>difficulty of grid systems in web pages</description>
<dc:creator>cheeaun</dc:creator>
<dc:date>2005-05-29T08:44:00Z</dc:date>
<dc:subject>grid pages web</dc:subject>
<taxo:topics>
<rdf:Bag>
<rdf:li resource="http://del.icio.us/tag/grid" />
<rdf:li resource="http://del.icio.us/tag/web" />
<rdf:li resource="http://del.icio.us/tag/pages" />
</rdf:Bag>
</taxo:topics>
</item>

These tags might be useful for some people so I decided to wrap up few PHP codes to display them as visible data. So, the above feed item would be parsed into this:

<ul>
...
<li><a href="http://www.mezzoblue.com/archives/2005/05/13/columns_grid/" title="difficulty of grid systems in web pages">Columns &amp; Grids</a>
<span class="tags">tags:
<a href="http://del.icio.us/tag/grid" rel="tag">grid</a>,
<a href="http://del.icio.us/tag/pages" rel="tag">pages</a>,
<a href="http://del.icio.us/tag/web" rel="tag">web</a></span>
</li>
...
</ul>

Generally, anyone who go to these tagged pages, are the ones who are curious to find for more resources applied with the same tag or relevant tags. When people go to del.icio.us's tag pages, they can view more other similar bookmarks and explore further. Regarding the rel="tag" code for the links, it is one of several MicroFormats and is documented in the RelTag draft specification.

After applying these, I realise that the way I display the tags for my social bookmarks looks quite similar to Tantek's tags list, except that he uses the list module while I use commas to separate the adjacent links. Also, he tags his weblog posts. My weblog doesn't have any tagging system or category-based archiving, because Blogger doesn't like them, yet.

Then I start to wonder, why would bloggers categorise their weblog posts with tags that link to Technorati's Tag index? Compared to del.icio.us's tag pages, Technorati gathers more resources on that specific tag from its own database and various sites such as Flickr, Furl and del.icio.us. It is much better, so I just modify my link roll codes to point the tag links to Technorati instead.

Recently, I also discovered Bud Gibson's xFolk microformat which facilitates decentralised bookmark tagging. It's an interesting approach. To conform with xFolk, I altered the link roll codes, plus changing the tag links to Technorati's, to this:

<ul>
...
<li class="xfolkentry"><a href="http://www.mezzoblue.com/archives/2005/05/13/columns_grid/" title="difficulty of grid systems in web pages" class="taggedlink">Columns &amp; Grids</a>
<span class="tags">tags:
<a href="http://technorati.com/tag/grid" rel="tag">grid</a>,
<a href="http://technorati.com/tag/pages" rel="tag">pages</a>,
<a href="http://technorati.com/tag/web" rel="tag">web</a></span>
</li>
...
</ul>

As you might notice, the extended class is excluded because in my opinion, the values in the title attribute is functional enough to describe the tagged link. Yet, that class name is not semantical enough, though. Extended what? You get the point.

On a related matter, my weblog is exactly one year old by today. Unbelievable, my weblog actually survives this long. Thanks to everyone who reads my weblog!