There is a great basic introduction to metadata and taxonomy over on the blog Brain Traffic. This post simplifies these often intimidating concepts and even includes helpful diagrams. From the main types of metadata and how they work together to taxonomies and controlled vocabularies, this post sums it all up beautifully in the section “Let’s Get Together, yeah yeah yeah.”
At its simplest, a taxonomy organizes information, and metadata describes it.
Culminating with a handy resource list pointing to some of the usual suspects (NISO) as well as to some less mainstream blogs and workshops, this is an awesome starting point for anyone hoping to learn more about metadata and taxonomy sans head spinning.