Metadata is data about data and is a core issue in digital preservation. Metadata adds value to the data that needs to be preserved and is used for describing, administering and retrieving data. In digital preservation several kinds of metadata need to be created and maintained.
Some metadata will be created by the producer of the digital object, often called “original metadata” and during the digital life cycle other metadata will be added by the organization before the digital objects will be ingested into the repository. It is important that the organisation defines its policies for metadata.
The original metadata that comes with the digital object files must be kept to ensure provenance and authenticity of the digital objects and can be of many different kinds. These metadata will be static compared to other types of metadata that can be generated and extended when or after the digital collection is deposited.
Besides the original metadata using with the metadata types below would be advisable. Descriptive metadata or bibliographic metadata is used for describing the collection or the digital object (who, what, when, where etc.). The preservation metadata (administrative metadata, technical metadata, rights management metadata etc.) describes information that are needed to be able to perform long term preservation of the digital collection, e.g. origin, digitization metadata, technical environment necessary to maintain access to the digital object etc. Structural metadata contains information on how to understand the digital object including what file types a digital object consists of etc.
To these different kinds of metadata different standards apply. For descriptive metadata e.g. MODS, DCMI or MARC are well known standards. For preservation metadata the standards PREMIS and MIX among others can be used, and for structural metadata METS is an example of a useful standard.
Literature on the topics in this chapter can be found at