How do communities use tagging?

Communities can use a set of tags as communal keywords, thus creating shared set of pointers to resources relevant to members. A “tag cloud” (the set of tags that a community uses sized according to frequency of use) can be a way to represent dynamically what a community is interested in and where its learning is focusing. It can be interesting for members to visualize their membership by comparing their own tag cloud that of their community.

A tag can also have its own “feed”. This means that members can stay subscribed to a tag, being notified when content tagged with a specific term is used.