Did the word "folksonomies" throw anyone else? I am embarrassed to say I went to Wikipedia, but it seemed an appropriate and easy-to-read source:

Folksonomy

From Wikipedia, the free encyclopedia

A folksonomy is a user-generated taxonomy used to categorize and retrieve web content such as Web pages, photographs and Web links, using open-ended labels called tags. Typically, folksonomies are Internet-based, but their use may occur in other contexts. The folksonomic tagging is intended to make a body of information increasingly easy to search, discover, and navigate over time.