In library and archival science, digital preservation is a formal endeavor to ensure that digital information of continuing value remains accessible and usable. It involves planning, resource allocation, and application of preservation methods and technologies, and it combines policies, strategies and actions to ensure 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. The Association for Library Collections and Technical Services Preservation and Reformatting Section of the American Library Association, defined digital preservation as combination of "policies, strategies and actions that ensure access to digital content over time." According to the Harrod's Librarian Glossary, digital preservation is the method of keeping digital material alive so that they remain usable as technological advances render original hardware and software specification obsolete.
Appraisal is performed on all archival materials, not just digital. It has been proposed that, in the digital context, it might be desirable to retain more records than have traditionally been retained after appraisal of analog records, primarily due to a combination of the declining cost of storage and the availability of sophisticated discovery tools which will allow researchers to find value in records of low information density. In the analog context, these records may have been discarded or only a representative sample kept. However, the selection, appraisal, and prioritization of materials must be carefully considered in relation to the ability of an organization to responsibly manage the totality of these materials.
Another common type of file identification is the filename. Implementing a file naming protocol is essential to maintaining consistency and efficient discovery and retrieval of objects in a collection, and is especially applicable during digitization of analog media. Using a file naming convention, such as the 8.3 filename, will ensure compatibility with other systems and facilitate migration of data, and deciding between descriptive (containing descriptive words and numbers) and non-descriptive (often randomly generated numbers) file names is generally determined by the size and scope of a given collection. However, filenames are not good for semantic identification, because they are non-permanent labels for a specific location on a system and can be modified without affecting the bit-level profile of a digital file.
Unintentional changes to data are to be avoided, and responsible strategies put in place to detect unintentional changes and react as appropriately determined. However, digital preservation efforts may necessitate modifications to content or metadata through responsibly-developed procedures and by well-documented policies. Organizations or individuals may choose to retain original, integrity-checked versions of content and/or modified versions with appropriate preservation metadata. Data integrity practices also apply to modified versions, as their state of capture must be maintained and resistant to unintentional modifications.
Characterization of digital materials is the identification and description of what a file is and of its defining technical characteristics often captured by technical metadata, which records its technical attributes like creation or production environment.
Proper understanding of the significant properties of digital objects is critical to establish best practice approaches to digital preservation. It assists appraisal and selection, processes in which choices are made about which significant properties of digital objects are worth preserving; it helps the development of preservation metadata, the assessment of different preservation strategies and informs future work on developing common standards across the preservation community.
Preservation metadata is a key component of digital preservation, and includes information that documents the preservation process. It supports collection management practices and allows organizations or individuals to understand the chain of custody. Preservation Metadata: Implementation Strategies (PREMIS), an international working group, sought to "define implementable, core preservation metadata, with guidelines/recommendations" to support digital preservation efforts by clarifying what the metadata is and its usage.
International Research on Permanent Authentic Records in Electronic Systems (InterPARES) is a collaborative research initiative led by the University of British Columbia that is focused on addressing issues of long-term preservation of authentic digital records. The research is being conducted by focus groups from various institutions in North America, Europe, Asia, and Australia, with an objective of developing theories and methodologies that provide the basis for strategies, standards, policies, and procedures necessary to ensure the trustworthiness, reliability, and accuracy of digital records over time.
Digital content can also present challenges to preservation because of its complex and dynamic nature, e.g., interactive Web pages, virtual reality and gaming environments, learning objects, social media sites. In many cases of emergent technological advances there are substantial difficulties in maintaining the authenticity, fixity, and integrity of objects over time deriving from the fundamental issue of experience with that particular digital storage medium and while particular technologies may prove to be more robust in terms of storage capacity, there are issues in securing a framework of measures to ensure that the object remains fixed while in stewardship.
In 2002 the Preservation and Long-term Access through Networked Services (PLANETS) project, part of the EU Framework Programmes for Research and Technological Development 6, addressed core digital preservation challenges. The primary goal for Planets was to build practical services and tools to help ensure long-term access to digital cultural and scientific assets. The Open Planets project ended May 31, 2010. The outputs of the project are now sustained by the follow-on organisation, the Open Planets Foundation. On October 7, 2014 the Open Planets Foundation announced that it would be renamed the Open Preservation Foundation to align with the organization's current direction.