Digital preservation metadata is particularly important for repositories, places where information objects are stored and managed for a long time.
[3] In the early 2000s it became clear that a shared community metadata standard was needed to ensure long-term preservation of the ever-increasing digital resources.
The use of standards is important as it supports the development of a community of best practice; it helps practitioners learn from the insights of others, so that they do not inadvertently overlook key metadata in their own practice; it allows for development of tools to make metadata creation and management easier; and it enables organizations to more easily exchange information with each other.
PREMIS was “charged to define a set of semantic units that are implementation independent, practically oriented, and likely to be needed by most preservation repositories”.
In December 2004 the PREMIS working group published its report, Implementing Preservation Repositories for Digital Materials: Current Practice and Emerging Trends in the Cultural Heritage Community.
The earlier Framework and the PREMIS Data Dictionary build on the Open Archival Information System (OAIS) reference model.
Differences usually reflect the fact that PREMIS semantic units require more specificity than the OAIS definitions provide, which is to be expected when moving from a conceptual framework to an implementation.
[12] Most of the semantic units listed in the data dictionary relate to Object and Event entities, the former being further divided into three subtypes of file, bitstream, and representation.
[12] Finally, the inclusion of rights entities responds to an increased awareness of and concern for the legal requirements of copyright and licensing.
[15] PREMIS data dictionary entries include twelve attribute fields, not all of which are applied to every semantic unit (analogous to an "element" in other metadata schemes).