What is dublin core?

Answer 1

Dublin Core is an initiative to create a digital "library card catalog" for the Web. Dublin Core is made up of 15 metadata (data that describes data) elements that offer expanded cataloging information and improved document indexing for search engine programs.

Two forms of Dublin Core exist: Simple Dublin Core and Qualified Dublin Core. Simple Dublin Core expresses elements as attribute-value pairs using just the 15 metadata elements from the Dublin Core Metadata Element Set. Qualified Dublin Core increases the specificity of metadata by adding information about encoding schemes, enumerated lists of values, or other processing clues. While enabling searches to be more specific, qualifiers are also more complex and can pose challenges to interoperability.