A persistent identifier (PID) is a unique code assigned to an object or person that helps to distinguish it from other objects or people. All persistent identifiers have to fulfil the following requirements:
- each identifier has to be associated with a specific clearly defined resource (object, person, institution, etc.);
- the textual and/or numeric value of each identifier has to be unique;
- the identifier and the resource it leads to have to persist over time (that is, it has to be unchanging).
PIDs are used in many domains. One of the more widely known examples are national identification numbers issued by many states to their citizens.
Born-digital PIDs also function as URLs that lead to the identified object or its description on the web.
Here are the main PIDs used in scholarly communication:
| ARK (Archival Resource Key) | PID used for information objects (digital objects and web records of physical objects). Can be used as an alternative to DOI. |
| DOI (Digital Object Identifier) | One of the most popular PIDs to be used in scholarly communication. Theoretically, a DOI can be used for any digital or physical object, but in practice, it is most commonly used for intellectual property objects such as articles, presentations or datasets. |
| Handle | PID used for digital objects. Can be used as an alternative to DOI. |
| ISBN (International Standard Book Number) | PID for printed and electronic books. |
| ISSN (International Standard Serial Number) | An ISBN-twin used to identify serial publications. |
| ORCID iD (Open Researcher and Contributor ID) | PID used to identify academic authors and contributors. Every researcher can sign up for an ORCID iD for free at https://orcid.org/register. Here is a video tutorial on how to register for an ORCID iD. |
| RAiD (Research Activity Identifier) | PID for research projects. |
| ResearcherID | An author PID used by the Web of Science database owned by Clarivate. Outside of Web of Science, authors are recommended to use the non-proprietary ORCID iDs. |
| ROR (Research Organization Registry) | PID for research organisations. |
In most cases, a PID is managed by a specific organisation whose aim is to ensure that the identifier remains reliable, unique and persistent and to maintain the technical infrastructure on which the identifier runs. For example, ISBNs are managed by the International ISBN Agency, and DOIs are managed by the International DOI foundation (IDF).
Need some advice?
Questions on topics related to research data management can be directed to Dr Gintė Medzvieckaitė from the Scientific Information and Data Division.
Scholarly Communication and Information Centre
Saulėtekio al. 5 (Block B, 4th floor, Room 403)
Phone: +370 5 219 5062
Email:
Contact via MS Teams
The Scientific Information and Data Division also offers training events on topics related to Open Science and research data management. Please contact the Head of Scientific Information and Data Division Gitana Naudužienė if you would like to request a training activity in English (a group of 5 or more attendees is required).