Glossary

Archive Information Package (AIP) – An information package consisting of the Content Information and the associated Preservation Description Information (PDI), which is preserved within an OAIS.

Checksum – A hash function that is commonly used to detect errors in files and compare multiple versions of files to detect changes. To learn more, see this post from The Signal.

Codec – A device or program that compresses data to enable faster transmission and decompresses received data.

Creative Outputs – Larger-scale digital projects are often multi-faceted, containing any number of different creative outputs, such as websites, datasets, exhibitions, software, or written publications. Each of these can be usefully considered as “sites of production” within a project, especially in the context of project recordkeeping.

Designated Community – Users, imagined or identified; this term is used in the OAIS.

Dissemination Information Package (DIP) – An information package derived from one or more AIPs, received in response to a request to the OAIS.

Emulation – A technique used to overcome the technical obsolescence of hardware and software by imitating obsolete systems on later generations of computers.

Fixity – A term used to indicate that a file has not been accidentally or purposefully changed.

Hash – A hash function transforms a string of characters into another (usually shorter) string of characters (a hash value). To learn more, see this post from The Signal.

Metadata – Commonly referred to as “data about data,” this is information that provides context to a digital object. Several common metadata types are introduced below, and more extensive information can be found in Jenn Riley’s Understanding Metadata: What is Metadata and What is it For?

    • Administrative – Metadata that provides information needed to manage a resource, such as when and how it was created, file type, and access privileges.
    • Descriptive – Metadata that describes a resource for purposes such as discovery and identification. It can include elements such as title, abstract, author, and keywords.
    • Preservation – Metadata that documents and supports the digital preservation process. PREMIS has become the de facto standard for preservation metadata.
    • Technical – Metadata that describes the technical processes used to produce, or required to use a digital object.
    • Transformative – Metadata that shows how attributes of a digital object have changed from the object’s origins to its current or final form
    • Use – Metadata that documents user access, user tracking and versioning information.

Migration – A strategy used to overcome technological obsolescence by transferring digital resources from one generation of  hardware or software to the next. The purpose of migration is to preserve the intellectual content of digital objects within modern systems, supporting the retrieval and access of content.

Open Archival Information System (OAIS) – A conceptual framework for an archival system dedicated to preserving and maintaining access to digital information over the long term. Its purpose is “to increase awareness and understanding of concepts relevant for archiving digital objects, especially among nonarchival institutions; elucidate terminology and concepts for describing and comparing data models and archival architectures; expand consensus on the elements and processes endemic to digital information preservation and access; and create a framework to guide the identification and development of standards.” For more information, see OCLC’s guide.

Open Format– A file format that can be used an implemented by anyone with no monetary restrictions; in contrast with a closed format, which can be a trade secret. These are considered more accessible and sustainable, as they can be opened and read correctly with a range of software products. The structure of an open format is often set out in agreed standards, overseen and published by a non-commercial expert body.

Optical Media – Discs that are read by a laser, including CD-ROMs, DVD-ROMs, and all variations of these two formats.

Submission Information Package (SIP) – An information package that is delivered to the OAIS for use in the construction or update of one or more Archival Information Packages (AIPs).

Sustainable Format – A file format that enables access regardless of the specific technologies used to create the file. Sustainable formats increase the likelihood that a record will be accessible in the long term.

Write-blocker – A device that allows for the acquisition of information on a drive without allowing for accidental damage to or deletion of the drive’s contents. This is accomplished by allowing only read commands, and preventing (or “blocking”) write commands.

(Last updated April 2018)