Digital object identifier

Definition and Purpose of Digital Object Identifier (DOI)
– DOI is a persistent identifier used to uniquely identify various objects.
– It is standardized by the International Organization for Standardization (ISO).
– DOIs are widely used to identify academic, professional, and government information.
– They are used for journal articles, research reports, data sets, and official publications.
– DOIs aim to resolve to the target information object they refer to.

DOI Nomenclature and Syntax
– A DOI consists of a prefix and a suffix, separated by a slash.
– The prefix identifies the registrant of the identifier.
– The suffix is chosen by the registrant and identifies the specific object.
– Most legal Unicode characters are allowed in DOI strings.
– The prefix usually takes the form ’10.NNNN’ where NNNN is a number.

Display and Resolution of DOIs
– The official DOI Handbook recommends displaying DOIs as ‘doi:10.1000/182’.
– CrossRef, a major DOI registration agency, recommends displaying a URL instead.
– The URL format is ‘https://doi.org/10.1000/182’.
– This URL is persistent and redirects to the correct online location.
– The entire URL is displayed to facilitate copying and pasting.
– DOI names can be resolved using a DOI resolver like doi.org.
– DOIs can also be included in documents as URLs using the resolver as an HTTP proxy.

Content Covered by DOI System
– DOIs are used for scholarly materials such as journal articles and books.
– Research datasets are also assigned DOIs.
– European Union official publications have DOIs.
– Chinese academic journals and the Chinese National Knowledge Infrastructure project use DOIs.
– DOIs are used for permanent global identifiers for audio/visual content.

Features, Benefits, and Comparison of DOI System
– DOIs provide persistent identification for objects.
– Each DOI name permanently and unambiguously identifies the associated object.
– Metadata is associated with DOIs, providing relevant information about the objects.
– DOI names can be resolved to web locations where the objects can be found.
– The DOI system combines the Handle System, indecs Content Model, and social infrastructure.
– DOI names identify an object itself, not just its location.
– DOI system makes a collection of identifiers actionable and interoperable.
– DOI system offers persistent, semantically interoperable resolution.
– DOI system can include identifiers from many other controlled collections.
– Other identifier systems may lack functionality and accompanying metadata.

Digital object identifier (Wikipedia)

A digital object identifier (DOI) is a persistent identifier or handle used to uniquely identify various objects, standardized by the International Organization for Standardization (ISO). DOIs are an implementation of the Handle System; they also fit within the URI system (Uniform Resource Identifier). They are widely used to identify academic, professional, and government information, such as journal articles, research reports, data sets, and official publications. DOIs have also been used to identify other types of information resources, like commercial videos.^{[not verified in body]}

Digital object identifier

Full name	Digital object identifier
Acronym	DOI
Organisation	International DOI Foundation
Introduced	2000; 24 years ago (2000)
Example	10.1000/182
Website	www.doi.org

A DOI aims to resolve to its target, the information object to which the DOI refers. This is achieved by binding the DOI to metadata about the object, such as a URL where the object is located. Thus, by being actionable and interoperable, a DOI differs from ISBNs or ISRCs which are identifiers only. The DOI system uses the indecs Content Model for representing metadata.

The DOI for a document remains fixed over the lifetime of the document, whereas its location and other metadata may change. Referring to an online document by its DOI should provide a more stable link than directly using its URL. But if its URL changes, the publisher must update the metadata for the DOI to maintain the link to the URL. It is the publisher's responsibility to update the DOI database. If they fail to do so, the DOI resolves to a dead link, leaving the DOI useless.

The developer and administrator of the DOI system is the International DOI Foundation (IDF), which introduced it in 2000. Organizations that meet the contractual obligations of the DOI system and are willing to pay to become a member of the system can assign DOIs. The DOI system is implemented through a federation of registration agencies coordinated by the IDF. By late April 2011 more than 50 million DOI names had been assigned by some 4,000 organizations, and by April 2013 this number had grown to 85 million DOI names assigned through 9,500 organizations.