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Collaboration in the Digital Age
June 24 and 25, 2008
Denver Public Library, Colorado Historical Society, and Denver
Art Museum
Denver, Colorado
Glossary
Compiled by the Institute of Museum and Library Services and
Heritage Preservation
Also consult the Care
of Audio-Visual Materials and Care
of Digital Materials sections of the Guide
to Online Resources for links to additional information
sources.
authentication
A mechanism that attempts to establish the authenticity of
digital materials at a particular point in time. For example,
digital signatures.4
authenticity
The digital material is what it purports to be. In the case
of electronic records, it refers to the trustworthiness of
the electronic record as a record. In the case of "born
digital" and digitized materials, it refers to the fact
that whatever is being cited is the same as it was when it
was first created unless the accompanying metadata indicates
any changes. Confidence in the authenticity of digital materials
over time is particularly crucial owing to the ease with which
alterations can be made.4
born digital
Digital materials which are not intended to have an analog
equivalent, either as the originating source or as a result
of conversion to analog form.4
compression
The re-encoding of data to make it smaller. Most image file
formats use compression because image files tend to be large
and consume large amounts of disk space and transmission time
over networks.6
controlled vocabulary
Formal limits on a vocabulary, useful for consistent use of
vocabulary terms.6
content file
A file that is either born digitally or produced using various
kinds of capture application software. Audio, image, text,
and video are the basic kinds of content files.2
digital assets
A collection of computer files that contain intellectual content
(images, texts, sounds, video) and/or descriptive metadata
of the content and its digital format. They represent an investment
for the depositor and an information resource for the researcher.2
digital materials
A broad term encompassing digital surrogates created as a
result of converting analog materials to digital form (digitization),
and "born digital" for which there has never been
and is never intended to be an analog equivalent, and digital
records.4
digital object
An abstraction that can refer to any type of information.
The object may be simple or complex, ranging from values used
in databases to graphics and sounds. Objects are not necessarily
self-contained, for example, a graphics object may require
an external piece of software to render the image. In addition
to the data that makes up the fundamental content, the object
often includes metadata that describes the resource in a manner
that supports administration, access, or preservation.5
digital preservation
Combination of policies, strategies and actions to ensure
the access to reformatted and born digital content regardless
of the challenges of media failure and technological change.
The goal of digital preservation is the accurate rendering
of authenticated content over time.1
digital provenance
A record of all migrations, transformations, or translations
performed on a digital object from its original creation to
the present time.2
digitization
The process of creating digital files by scanning, audio transfer,
or otherwise converting non-digital materials.
documentation
The information provided by a creator and the repository,
which provides enough information to establish provenance,
history, and context and to enable its use by others.4
electronic records
Records created digitally in the day-to-day business of the
organization and assigned formal status by the organization.
They may include word processing documents, emails, databases,
or intranet web pages.4
finding aid
A tool used to communicate the contents of an archival collection,
the finding aid typically includes administrative information,
contextual information, scope and content information, intellectual
organization and physical location information for archival
and manuscript materials.6
fixity
The quality that a digital file has not changed in any way
between two points in time.
image capture
Using a scanner, digital camera, or other device to create
a digital representation of an object.6
image file format
A standardized way of storing digital image data. Different
file formats commonly use different methods of compression.
Some image file formats include JPEG, JPEG2000, TIFF, PNG,
BMP and GIF.
ingest
The process by which a digital object or metadata package
is absorbed by a different system than the one that produced
it.2
interoperability
The ability of multiple systems, using different hardware
and software platforms, data structures, and interfaces, to
communicate, exchange, and share data.6
JPG, JPEG
Joint Photographic Experts Group. An 8-24 bit image file format
that is best suited for photographs. It supports "lossiness,"
which means that it will throw away some detail in order to
achieve better compression. It has variable amount of compression
to vary quality and file size. It does not work well for text.
Widely used as a delivery format.6
JPEG2000
An image file format based on an image compression standard
that supports both lossy and lossless compression. While not
yet supported as widely as JPEG or TIFF, JPEG2000 is becoming
more popular both as a delivery format and as an archival
format.
life-cycle management
Proactive approach to the management of digital materials
that recognizes, whatever their form or function, digital
materials need to be actively managed at each stage of its
life and that each stage of a digital materials life affects
another stage so digital preservation activities should begin
early as practicable. This is different from traditional preservation,
where management is largely passive until detailed conservation
work is required, typically, many years after creation and
rarely, if ever, involving the creator.4
LOCKSS (Lots of Copies Keep Stuff Safe)
Technology designed to preserve copies of electronic publications
by ensuring that multiple copies are stored at different organizations.
See http://lockss.stanford.edu.
lossless
Characteristic of compression schemes where information is
not permanently lost in compression.
lossy
Characteristic of compression schemes where information is
permanently lost in compression.
metadata
Information that describes, explains, locates, and otherwise
makes it easier to retrieve and use an information resource.6
administrative metadata
Metadata primarily intended to facilitate the management of
resources.6
descriptive metadata
Metadata primarily intended to serve the purposes of discovery,
identification, and selection.6
metadata harvesting
A technique for extracting metadata from individual repositories
and collecting it in a central catalog to facilitate search
interoperability.6
metadata scheme
A set of metadata elements and rules for their use that has
been defined for a particular purpose.6
preservation metadata
Metadata primarily intended to help manage the process of
ensuring the long-term preservation and usability of digital
information resources.6
rights metadata
Metadata primarily intended to enable the management of rights
related to information resources; a type of administrative
metadata.6
structural metadata
Metadata that describes the internal organization of a resource
and its place in an external organization, including any relationships
it has with other resources,6 e.g., the sequence of pages
for a group of images of a diary or of detailed images of
a larger image.2
technical metadata
Metadata primarily intended to document the creation and characteristics
of digital files.6
migration
A means of overcoming technological obsolescence by transferring
digital resources from one hardware/software generation to
the next. The purpose of migration is to preserve the intellectual
content of digital objects and to retain the ability for clients
to retrieve, display, and otherwise use them in the face of
constantly changing technology. Migration differs from the
refreshing of storage media in that it is not always possible
to make an exact digital copy or replicate original features
and appearance and still maintain the compatibility of the
resource with the new generation of technology.4
persistent identifier
A unique code that identifies a digital object within the
central repository.
OAI (Open Archives Initiative)
An organization that has developed interoperability standards
to facilitate the efficient dissemination of online content.
For more information about its two major projects, the Open
Archives Initiative Protocol for Metadata Harvesting (OAI-PMH)
and the Open Archives Initiative Object Reuse and Exchange
(OAI-ORE), see http://www.openarchives.org.5
OAIS (Open Archival Information System)
An archival method based on the Reference Model for an Open
Archival Information System (OAIS) (http://public.ccsds.org/publications/archive/650x0b1.pdf).
An archive that uses this method consists of an organization
of people and systems that has accepted the responsibility
for information deemed to need long term preservation and
make it available for a designated community.
PDF
Portable Document Format, 4-64 bit depth. Uncompressed. Used
mainly to image documents for delivery. Need plug-in or Adobe
application to view. Adobe's Portable Document Format, the
term Adobe uses to describe Acrobat files.6
quality control
Techniques used to ensure that high quality is maintained
through the various stages of digitization.6
reformatting
Copying information content from one storage medium to a different
storage medium (media reformatting) or converting from one
file format to a different file format (file re-formatting).4
refreshing
Copying information content from one storage media to the
same storage media.4
resolution
The number of pixels (in both height and width) making up
an image. The more pixels, the higher the resolution; the
higher the resolution, the greater its clarity and definition
and the greater the file size. Can be expressed as a ratio
(640 x 480 pixels) or in terms of dots per inch (dpi).6
scanning
See digitization.
server
Host computer for web pages, applications, or services.6
surrogate
A secondary object meant to substitute for the original, such
as a photograph of an artwork used in place of the artwork.6
tag
A keyword used to describe a digital object.
thesaurus
A controlled vocabulary with syndectic structure in which
all allowable terms are given and relationships between terms
are shown.6
TIF, TIFF
Tagged Image File Format, an industry standard image file
format. Uncompressed, originally developed for desktop publishing.
1 to 64 bit depth, used mostly for high quality imaging and
archival storage. Generally non-compressed and high quality,
including large file sizes. Most TIFF readers only read a
maximum of 24-bit color.6
trusted repository
An entity whose mission is to provide reliable, long-term
access to managed digital resources to its designated community,
now and in the future. Trusted digital repositories may take
different forms: some institutions may choose to build local
repositories while others may choose to manage the logical
and intellectual aspects of a repository while contracting
with a third-party provider for its storage and maintenance.7
validation
A process to check one or more aspects of a submission for
schema errors, file format problems, and ingest parameter
inconsistencies that might affect its suitability for preservation.
Results of a validation may include any combination of structural
analysis information, warning messages, or fatal errors that
prevent an object from being ingested.2
watermark (or digital watermark)
The process of embedding information in a digital image, audio,
or video file. In visible watermarking, the information is
typically text or a logo, which identifies the owner of the
file. In invisible watermarking, information is added as digital
data but it cannot be perceived as such, a technique often
used in copyright protection systems.
References
1 American Library Association,
Association for Library Collections & Technical Services,
Preservation and Reformatting Section, Definitions of
Digital Preservation, 2008. http://www.ala.org/ala/alcts/newslinks/digipres
2 Colvin, Jennifer, Glossary,
California Digital Library, updated as of May 15, 2006.
http://www.cdlib.org/inside/diglib/glossary
3 Consultative Committee for Space
Data Systems, Reference Model for an Open Archival Information
System (OAIS), 2002. http://public.ccsds.org/publications/archive/650x0b1.pdf
4 Digital Preservation Coalition,
Maggie Jones, and Neil Beagrie. “Introduction: Definitions
and Concepts” from Preservation Management of Digital
Materials: A Handbook, 2001 (maintained online). http://www.dpconline.org/text/intro/definitions.html
5Moses, Richard Pearce. A Glossary
of Archival and Records Terminology. Society of American
Archivists, 2005. http://www.archivists.org/glossary
6 North Carolina Exploring Cultural Heritage
Online, Glossary, 2007. http://www.ncecho.org/guide/glossary.htm
7 RLG, Trusted Digital Repositories:
Attributes and Responsibilities. RLG-OCLC, 2002.
ttp://www.oclc.org/programs/ourwork/past/trustedrep/repositories.pdf
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