Dublin Core metadata element set

Dublin Core is a simple metadata element set designed to facilitate discovery of electronic resources, especially webpages, image files, and other multimedia assets.

The website includes links to specifications and describes the element set as:

The Dublin Core Metadata Element Set is a vocabulary of fifteen properties for use in resource description. The name “Dublin” is due to its origin at a 1995 invitational workshop in Dublin, Ohio; “core” because its elements are broad and generic, usable for describing a wide range of resources.