Metadata Elements

A metadata record consists of all the metadata elements describing an object. Metadata records are often expressed in XML or other machine-readable formats for easy integration within systems. There are three basic categories of metadata elements: descriptive, technical/structural, and administrative.

As a side note, I really love how this graphic is laid out. Whereas I know I've seen these elements in a lot of different settings, including in cataloging, I've found it difficult to rattle these off from the top of my head. This image almost puts them in concrete memory because of how they are laid out in an almost common sense way, showcasing why each element is the way it is, and where it should be. 

Sources: http://dublincore.org/documents/dces/