What makes tags so appealing is that they are:
1. User-contributed (the user determines what tags to apply to an item)
2. User-defined (the users determine what tag to apply to a concept)
There is a consensus-building process that seeks to answer "what is the
best tag for this concept / this item?" From the point of view of the
users, the answer is "whatever enables folks to find this concept / this item".
Criterion: by frequency
Tag frequency is a technique that systems have to make it easier for users
to find concepts and items tagged with those concepts. We often see a nice
control that visualizes this frequency information. It displays tags for a
pool of items with increasing emphasis in proportion to the frequency with
which the tag is used.
Criterion: by category
A system of categories is another way to enable users to find concepts or
items. It doesn't necessarily interfere with users' ability to contribute
new tags or to define what the tags stand for.
There may be tags that belong to no category. There may be tags that are
contributed with no category information that are later adopted into the
category scheme. And there may be tags that are given a suggested category
when they are submitted, and are either automatically adopted into that
category, or are adopted if a moderator approves.
What categories clash with is a third aspect of the appeal of tags:
3. Unsupervised (which tags become prominent is entirely an emergent
property of the tagging ecosystem)
In agriculture, you get better produce if you do some cultivating by
encouraging promising species that seem to have use to humans, by finding
ways to encourage the growth of particular crops, and (more controversial
to some) by finding ways to breed better crops.
It's natural to expect that in tagging systems, a little cultivation could
help a lot. Once valuable tags emerge, categories are a reasonable way to
An officially-recognized tag need not entirely crowd out other useful tags
for closely-related concepts. Often, based on one tag, you can obtain a
pool of related tags.
At 09:34 AM 12/1/2006, Sunandini Basu wrote:
>Is it a good practice to categorise tags? > >as far as i know, tags are meant to be non-linear. del.icio.us has 2 ways to >organize tags - alphabetically and by frequency. >I was surprised to see MSN organizing tags by grouping them under >categories<http://qna.live.com/BrowseTags.aspx>. > >doesn't that totally go against the whole concept of tags? > >Best, >Soo