clipped from: atomiq.org   

This is my cheat sheet for the paper "Position Paper, Tagging, Taxonomy, Flickr, Article, ToRead" (PDF). I'd recommend reading it (if you find tagging interesting you probably already have) but I wanted to extract its two conceptual taxonomies. They're helpful for thinking about tagging systems but the paper buries them a bit.

The paper deals mainly with social tagging systems, and it uses the classic tripartite model of tagging: resource (the thing being tagged), user (the person doing the tagging) and tags (the tag connecting the two).

  • Tagging Rights - who can tag what?
    1. Self-tagging - users can only tag their own contributions (e.g. Technorati)
    2. Permission-based - users decide who can tag their resources (e.g. Flickr), or some other design on the continuum between self-tagging and free-for-all
    3. Free-for-all - any user can tag any resource
  • Tagging Support - how does the interface support tag entry?
    1. Blind tagging - user cannot see the other tags assigned to the resource they're tagging
    2. Viewable tagging - users can see the other tags assigned to the resource they're tagging
    3. Suggestive tagging - user sees suggested tags for the resource they're tagging
  • Aggregation - how are tags aggregated for a given resource?
    1. Bag-model - the same tag can be assigned to a resource multiple times (allowing statistics to be generated and users to see if there is agreement among taggers about the content of the resource). This is very del.icio.us.
    2. Set-model - a tag can be applied only once to a resource, like in Flickr.