Pointers to implementing a taxonomy system?

Question

I am taking part in the development of a PHP CMS (yeah I know you are like, meeh). It is currently using simple tags for tagging content. What I want to do is push the whole thing to using Taxonomy but I am not sure on what to pay attention to, or how to go about structuring the whole vocabularies/terms.

I'd love to be able to keep the user interaction close to that of the current simple tags and at the same time allow for more advanced usage by power users.

The Drupal and the Wordpress taxonomy systems are being reviewed at the moment and they provide valuable resources. Nevertheless, it could be that someone has some simpler and more appropriate thoughts on this matter.

Answer 1

Things to consider:

• Helping users to do tagging with in-page UIs (enabled by AJAX/JQuery, CSS):

  • auto-complete of existing tags
  • automatic tag suggestion
  • allowing users to link tags as synonyms, opposite of synonyms
  • allowing users to define pronouns, common nouns
  • auto detection of non-nouns: the, it, at, etc.
  • tag hierarchies, families of tags
  • tag arithmetic/set theory: adding tags, excluding content by subtracting a tag, e.g. this but NOT that.
  • user's private and public tag sets, visibility of

• Content to be tagged

  • photos, video, users, events, applications. Able to link these content types through tags

• Applications

  • invent a tagged file system on Windows, Mac, Linux rather than the usual hierarchical, make backward compatible, to tag and link all kinds of files, apps, email

• Other projects

  • Look at Reuters OpenCalais

• Inter-operability

  • APIs with other systems, e.g. Drupal, Wordpress, YouTube, Flickr, del.icio.us

Edit:

More thoughts:

• Consider your market: where have Drupal, Wordpress, et al not succeeded in penetrating? You need a market to give you incentive to do more than re-invent the wheel. The answer I would say is businesses, business organisations, office life. As someone who's worked in four big organisations the recurring trend is
  • the disconnection of knowledge between inter-dependent organisations,
  • the mismatch in terminology causing ineffective communication - and indeed hindering meaningfulness of how products are used in the real world e.g. what marketing call products internally by code name and externally and how these match to software releases by the development teams
  • the repetitive tasks to seek knowledge,
  • having to derive knowledge via people when rather an effective software tool would do the same (e.g. getting someone to look something up for you). I don't mean replacing people.

I believe a taxonomy that can be embedded in corporate communications, products, services, customers, assets, locations, applications, databases, emails, meetings, people, people skill sets, then organisations would be more fluid and more effective. It is a fact of life that any organisation has heterogeneous systems, legacy systems, that need to work together, the key is to be able to link them together and reduce manual effort interlinking them.