These guidance notes were originally published at http://www.ukoln.ac.uk/jisc-ie/blog/identifiers-quick-reference/ [1].
Glossary of terms
(this page is heavily influenced by work done by Acuity Unlimited for the JISC [2])
| Term | Meaning | Notes |
|---|---|---|
| Identifier | A token (usually a number or a string of characters) used to refer to an entity (anything which can be referred to) | |
| Referent | The entity pointed to by the identifier | This entity could be a digital object such as the file containing a research paper, or a physical object such as an item in a museum collection, or a person or organisation, or it could even be an abstract concept such as a 'learning outcome' |
| Minting | The process of creating a new identifier, and of linking it to its referent | This process which will benefit from careful consideration of how the resulting identifier will be managed and used |
| Resolution | The process of retrieving the referent for a given identifier | This might be a digital object such as a file or photo, or it might be a proxy for this such as a metadata record describing an entity. |
| Co-referent | Identifiers are said to be 'co-referent' when they point to the same entity. | An example of where this concept is expressed is 'owl:sameAs' from the Web Ontology Language (OWL) specification [3]. An example of a service which identifies and exposes co-references is sameAs.org [4] |
| Actionable | Generally means an identifier which can be 'clicked' on to retrieve either a representation of the referent or metadata about it. | |
| Persistent Identifier (PID) | An identifier which:
Persistent identifiers are also generally assumed to be persistently actionable. |
|
| Universally Unique Identifier (UUID) | An identifier which is guaranteed to be globally unique | |
| Globally Unique Identifier (GUID) | Typically, a synonym for a UUID, often referring to Microsoft's implementation of the UUID standard. | |
| Uniform Resource Identifier (URI) | A Uniform Resource Identifier is a string of characters used to identify a name or a resource on the Internet. Such identification may enable interaction with representations of the resource over a network (typically the World Wide Web) using specific protocols. Schemes specifying a concrete syntax and associated protocols define each URI. URLs and URNs are both kinds of URI. Examples of URIs on the web are identifiers starting with "http:" or "mailto:". | http://tools.ietf.org/html/rfc3986 http://en.wikipedia.org/wiki/URI |
| HTTP URI | A URI whose retrieval mechanism is HTTP. Typically this is for the purposes of allowing practices linking data on the web using W3C standards such as RDF, SKOS and OWL. | |
| Uniform Resource Locator (URL) | A kind of URI that specifies where an identified web resource is available and the mechanism for retrieving it. Eg, URL http://www.example.com [5] specifies an address on the World Wide Web whose retrieval mechanism is specified by HTTP. |
Types of identifier commonly used in an HE context
| Type | Description | Notes |
|---|---|---|
| URI | URI is the identifier mechanism used by the Web | An HEI will typically own its own domain and mint its own URIs. |
| DOI | DOIs, or Digital Object Identifiers, are commonly used in the HE context to identify published articles in academic journals. DOIs are managed within a federation of agencies, a business arrangement which provides a degree of resilience and confidence in the persistence of DOIs | In this context, DOIs are typically minted by a publisher via a Registration Agency, which charges a fee. |