Metadata (referred to as “data about data”) is a term that is usually applied to descriptive information about digital (or non-digital) resources that machines can use in order to gather information about the content of your digital files. For digital oral history, metadata is particularly important for items, such as the audio files and photographs associated with the online collection (non-text items). This metadata can help the chances of the material being found on the web. In addition to discovery, metadata can also support the management, sustainability and re-use potential of digital collections (CDP Metadata Working Group 2006, page 4).
Why use metadata?
- Discovery (metadata helps users find things)
- Archiving/preservation (helps to ensure that digital files can be read into the future, when standards are used)
- Interoperability (helps information exchange, and to ensure that others can use it, again, when standards are used)
Metadata is usually divided into three types, descriptive, administrative and structural. Descriptive metadata describes what the resource is, what it is called, what type of content it contains and what it is about. Administrative metadata contains information such as the format of the digital file, details about when it was created and the rights associated with it (e.g. who owns it or holds copyright). Structural metadata describes the parts within the digital file, and how they are related (often with reference to another file that describes how the information is organised). (See GeoffFroh OHA 2008 talk at slideshare.)
Metadata can be bespoke, or it can be standardised. The history of the last few decades of digitisation projects has taught practitioners that bespoke systems, while specially designed for a collection and therefore carefully tailored to it, nevertheless inevitably become outdated. In order to be able to easily update these carefully curated resources, standards need to be applied.
“Adoption of standards is key to effective sharing of resources and interinstitutional interoperability.” (CDP Metadata Working Group 2006, page 6)
Benefits of standards
Standards are an agreed set of practices, whereby participants decide to work within a shared framework. This can help with interoperability (resources can be shared). Standards will ensure that later systems can be built around earlier collections, and can incorporate the cataloguing and metadata work that has been done in the past. Adhering to standards therefore makes a digitised resource sustainable in the long-term, and interoperable with other compatible systems in the short-term. The benefits include an assurance that time investment made in cataloguing, metadata creation and digitisation work will last more than a few short years before software technologies render it outmoded, and un-usable. Laying down clear guidelines can also help others learn how to create similar resources.
Dublin Core metadata standard
One of the most widely used metadata standards is Dublin Core (DC). DC is simple and general, and can therefore be used to describe almost any resource. It is:
- A standardised set of metadata elements that are used for describing digital objects (and can be used for non- digital objects as well)
- A very general set of descriptors that can be used to describe almost anything
- Widely supported
- Widely adopted because of its simplicity
DC started as a set of fifteen of elements that were deemed to be enough to describe almost any resource however the very general nature of the descriptors meant that some archives find that it is not enough. As a result of this, the DC list of elements has been significantly extended as part of the work carried out by the Dublin Core Metadata Initiative (DCMI). Many of the extended DC elements make the standard much easier to work with in the context of an oral history archive.
Despite this, there are also other metadata standards that could be used with oral history collections. For example, Encoded Archival Description (EAD) is an XML standard that is used to describe an archival resource. Decisions about which one to use will be based on disciplinary specificities, different use cases and different users, all of which contribute to the varying metadata requirements of any given resource or material/record type. (For a short discussion about choices of metadata standards for an oral history organisation, see this post “Oral history, metadata and choices about schema“.)
The advantage of DC is the fact that it is both simple to understand and widely used, meaning that there are a number of different crosswalks (procedures that allow you to transfer information from one metadata standard into another) that work with DC, ensuring that it can be widely used. For example, DC conforms to the Open Archives Initiative (OAI) protocol for metadata harvesting standards (see http://www.openarchives.org/pmh/) and DC is an accepted minimal metadata requirement for ingesting into internet portal for digital cultural heritage, Europeana (see http://www.europeana.eu/).
CDP Metadata Working Group. (2006). Dublin Core metadata best practices Version 2.1.1. Institute of Museum and Library Services and the Collaborative Digitzation Program at the University of Denver. Retrieved from http://www.mndigital.org/digitizing/standards/metadata.pdf. See page 4.
GeoffFroh. OHA 2008 – Making Sense of Metadata: A Practical Overview for Oral Historians. Retrieved from http://www.slideshare.net/GeoffFroh/oha-2008-making-sense-of-metadata-a-practical-overview-for-oral-historians-presentation (accessed 17 November 2014).
Open archive – http://www.openarchives.org/pmh/ (accessed 17 November 2014).
Europeana – http://www.europeana.eu/ (accessed 17 November 2014).