Does it seem to you that there’s a bewildering array of metadata standards out there?
Here’s a vivid illustration of how right you are:
http://www.dlib.indiana.edu/~jenlrile/metadatamap/
“This visual map of the metadata landscape is intended to assist planners with the selection and implementation of metadata standards.
“Each of the 105 standards listed here is evaluated on its strength of application to defined categories in each of four axes: community, domain, function, and purpose. The strength of a standard in a given category is determined by a mixture of its adoption in that category, its design intent, and its overall appropriateness for use in that category.”
From the linked page you can access three PDF files: A HUGE poster of the visualization (36 in. x 108 in.!), a metadata standard glossary in poster form (a more manageable 36 x 41 inches), and a metadata standard glossary in pamphlet form.