PREservation Metadata: Implementation Strategies (PREMIS) is the de facto digital preservation metadata standard.
Digital preservation metadata defines the information that is needed to ensure the long-term usability of digital objects to keep them accessible in some form in the future. Digital preservation metadata is particularly important for repositories, places where information objects are stored and managed for a long time. Simply storing digital objects on a data carrier is not enough to keep them usable. They need to be managed in a repository so that they are protected from accidental or intentional damage and so that a full computing environment can be created in which they can be accessed and understood when they are needed.
Information objects have descriptive metadata, information about the object that could be used to discover, access and identify the digital object. This metadata is, however, not enough to preserve the digital objects in the long-term. For example, the digital object's file format can become obsolete and unusable by future software applications. This would require either transforming the older format to a newer one (migration), or reproducing the original experience with newer technology (emulation). Both strategies would require the additional information, such as technical metadata about the original files, information about the older hardware and software that they ran on, and information about actions that have transformed the digital object over time. All of these are types of preservation metadata. Preservation metadata therefore supports activities intended to ensure the long-term usability of a digital resource.
In the early 2000s it became clear that a shared community metadata standard was needed to ensure long-term preservation of the ever-increasing digital resources. Experts from key memory institutions and repository developers joined together to define it, resulting in The PREMIS Data Dictionary for Preservation Metadata, which has become a de facto standard that defines core metadata needed by most preservation repositories.
The use of standards is important as it supports the development of a community of best practice; it helps practitioners learn from the insights of others, so that they do not inadvertently overlook key metadata in their own practice; it allows for development of tools to make metadata creation and management easier; and it enables organizations to more easily exchange information with each other.