Metadata principle 5: Good metadata supports the long-term management of items in collections.

Administrative metadata is information intended to facilitate the management of resources. It can include data such as when and how an object was created, who is responsible for controlling access to or archiving the content, what control or processing activities have been performed in relation to it, and what restrictions on access or use apply. Technical metadata, such as capture information, physical format, file size, checksum, sampling frequencies, etc., may be necessary to ensure the continued usability of an object, or to reconstruct a damaged object.

Preservation metadata is a subset of administrative metadata aimed specifically at supporting the long-term retention of digital objects. It may include detailed technical metadata as well as information related to the rights management, record keeping, management history, and change history of the object. It should, therefore, be compatible with the collections management workflow of organizations that manage collections. In some cases, this may require a negotiation to resolve institutional workflow and digital object descriptions.

• An OCLC/RLG Working Group called PREMIS (Preservation Metadata: Implementation Strategies) has developed a core set of preservation metadata. for release in 2004.
• The PADI (Preserving Access to Digital Information) clearinghouse at http://www.nla.gov.au/padi has a long annotated listing of resources related to preservation metadata. http://www.nla.gov.au/padi/topics/32.html
• NISO Z39.87 (AIIM 20-2002), Data Dictionary - Technical Metadata for Digital Still Images is one of the few formal standards for technical metadata. It focuses on images created by scanning. http://www.niso.org/standards/resources/Z39_87_trial_use.pdf

Archivists and records managers are particularly interested in record-keeping metadata.

• Recordkeeping Metadata Standards. Defines the metadata recommended by the National Archives of Australia for the recordkeeping systems of Australian government agencies. http://www.naa.gov.au/recordkeeping/control/rkms/summary.htm
• Australian Recordkeeping Metadata Schema. An effort to specify the whole range of recordkeeping metadata needed to manage records in digital environments. http://www.sims.monash.edu.au/research/rcrg/research/spirt/

Structural metadata relates the pieces of a compound object together. If a book consists of several page images, it is clearly not enough to preserve the physical image files; information concerning the order of files (page numbering) and how they relate to the logical structure of the book (table of contents) is also required. Three standards for packaging complex digital objects are the Metadata Encoding and Transmission Standard (METS), the IMS Content Packaging XML Binding, and the MPEG-21 Digital Item Declaration Language (DIDL). Of these, METS is most widely used in the cultural heritage community. METS is an XML schema that not only specifies how to represent structural metadata for an object, but also provides a framework for associating descriptive and administrative metadata. http://www.loc.gov/standards/mets/

Source: adapted from 'A Framework of Guidance for Building Good Digital Collections', published by the National Information Standards Office, 2nd edition, 2004.