Dictionary domainTrack B
The persistent identifier ecosystem
ORCID, ROR, RAiD, IGSN, PIDINST, DOIs — the PID landscape.
For implementers
Operational deployment checklist for The persistent identifier ecosystem: prerequisites, five deploy steps, integration notes for Pure, Symplectic Elements, Worktribe, DSpace, and more, plus the pitfalls that recur in the field.
Terms in this domain
77 terms
SocArXiv
<p><strong>SocArXiv</strong> is a free, open-access preprint repository for the social sciences. It was founded in 2016 by sociologist Philip N. Cohen in partnership with the nonprofit <a href='/guides/center-for-open-science'>Center for Open Science (COS)</a> and runs on the <a href='/dictionary/term/open-science-framework-osf'>Open Science Framework (OSF)</a> — the same underlying infrastructure that hosts <a href='/dictionary/term/osf-preprints'>OSF Preprints</a> and sibling branded servers such as <a href='/dictionary/term/psyarxiv'>PsyArXiv</a> (psychology) and engrXiv (engineering). SocArXiv launched alongside those two services on December 5, 2016, as part of COS's branded-server model, in which a scholarly community operates its own named, separately moderated preprint service on shared OSF backend infrastructure rather than building hosting from scratch.</p> <p>SocArXiv is not a COS-run editorial operation in the way a journal is. It is governed by a volunteer steering committee of scholars and library professionals under the banner "SocOpen," and since 2021 its institutional home has been the University of Maryland Libraries, which provides the administrative and legal footing for the service as an ongoing academic unit rather than a standalone nonprofit.</p> <h2>Operational definition</h2> <p>A deposit is properly identified as a "SocArXiv preprint" if it meets all of the following:</p> <ul> <li>It was submitted through the SocArXiv service on OSF (osf.io/preprints/socarxiv), not simply cross-listed or mirrored from another repository such as <a href='/guides/arxiv-preprints-what-they-are-and-how-to-use-them'>arXiv</a> or SSRN.</li> <li>It falls within sociology or a closely related social-science field — SocArXiv accepts working papers, preprints, published-paper copies, data, and code across the social sciences broadly, not sociology alone.</li> <li>It has passed SocOpen's moderation screen, which is a scope-and-completeness check, not peer review: moderators confirm the item is scholarly, falls within a supported research area, is plausibly categorized, is correctly attributed to its stated authors, is in a moderated language, and is submitted in a text-searchable format (PDF or DOCX, not a scanned image).</li> <li>It has received an automatically assigned, persistent <a href='/dictionary/term/doi'>DOI</a> on upload, making it citable independent of eventual journal publication; a prior DOI issued by another publisher can also be linked to the same record.</li> <li>It carries one of SocArXiv's permitted reuse terms — CC BY 4.0, CC0 (public-domain dedication), or no license — selected by the author at deposit.</li> </ul> <h2>What SocArXiv is not</h2> <p>Posting to SocArXiv is explicitly not peer review, and a SocArXiv record is not, by itself, evidence that a manuscript has been formally accepted anywhere. Moderation checks scope and completeness, not scientific merit, methodology, or novelty. SocArXiv is also free to authors and readers — there is no submission fee or paywall, which distinguishes it from many venues that require an <a href='/dictionary/term/article-processing-charge'>article processing charge (APC)</a> at the journal stage.</p> <h2>Examples</h2> <ul> <li>A sociologist deposits a working paper analyzing survey data on labor-market outcomes to SocArXiv ahead of submitting it to a peer-reviewed journal, receiving a citable DOI immediately and using that DOI in grant reports and CVs while the manuscript is still under review elsewhere.</li> <li>A research team posts the accepted-but-not-yet-typeset version of a political-science article to SocArXiv under a publisher-permitted embargo, satisfying a funder's open-access mandate without waiting for the journal's own publication date.</li> </ul> <h2>Counter-example</h2> <p>A working paper in economics or sociology posted only to SSRN, a university's own institutional repository, or a personal website is <em>not</em> a "SocArXiv preprint," even though it may cover an identical topic and serve a similar function — the term refers specifically to material submitted through and moderated by the SocArXiv service on OSF, not to social-science preprints in general (for that broader category, see <a href='/dictionary/term/preprint'>preprint</a>).</p> <h2>Related terms</h2> <ul> <li><a href='/dictionary/term/preprint'>Preprint</a></li> <li><a href='/dictionary/term/osf-preprints'>OSF Preprints</a></li> <li><a href='/dictionary/term/psyarxiv'>PsyArXiv</a></li> <li><a href='/dictionary/term/open-science-framework-osf'>Open Science Framework (OSF)</a></li> <li><a href='/dictionary/term/doi'>DOI</a></li> <li><a href='/guides/how-to-choose-a-preprint-server'>How to Choose a Preprint Server</a></li> <li><a href='/guides/preprint-servers-explained'>Preprint Servers Explained</a></li> </ul>
ANSI/NISO Z39.56 (SICI — Serial Item and Contribution Identifier)
A code counts as a SICI only if it assembles all three ANSI/NISO Z39.56-1996 [R2002] segments in sequence — an Item segment (ISSN + chronology + enumeration), a Contribution segment (starting page + title-code checksum for the specific article), and a Control segment (structure/version/check-character) — to identify one specific item within a serial. NISO withdrew the standard in 2012; new article-level identification now runs through the DOI.
Crossref Event Data
Crossref Event Data was a free Crossref service that captured and made available structured records of "events" -- online mentions such as tweets, Wikipedia citations, newspaper articles, blog posts, and Wikipedia edits -- that referenced scholarly content identified by a DOI. Each event linked a source (e.g. a specific tweet or Wikipedia page) to a subject (a DOI-identified research output) with a timestamp, and the resulting data fed into third-party altmetrics tools and dashboards. Crossref formally sunset the service: the public Event Data API and related infrastructure stopped being available from 23 April 2026, after roughly a decade in operation, and it should now be described in the past tense as a discontinued service, not an active one.
Published Data
<p>Data is 'published' when it has been formally released as a discrete, citable research output: deposited in a repository or registry that assigns it a persistent identifier (typically a DOI), described with metadata sufficient for independent discovery and reuse (at minimum the DataCite mandatory set -- Identifier, Creator, Title, Publisher, PublicationYear, ResourceType), and made accessible under a stated licence. A dataset that is merely stored, backed up, or informally emailed to a collaborator is not 'published' in this sense, even if the underlying files are identical -- publication is a formal act with a fixed citation form, not a description of where the bytes happen to live.</p>
shortDOI
A shortDOI is a redirect alias, in the form 10/abcde, generated by the International DOI Foundation's shortDOI Service (shortdoi.org) for an existing, already-registered DOI name. It is not a separately registered persistent identifier: it resolves through the same DOI Handle System and https://doi.org/ resolver as the underlying DOI, is issued only once per DOI (requesting a shortDOI for a DOI that already has one returns the existing alias rather than minting a new one), and carries none of a DOI's registration guarantees on its own -- the original DOI remains the identifier of record for citation, archiving, and metadata purposes.
Crossref Simple Text Query
<p>Crossref Simple Text Query is a free web-based matching tool at <a href='https://doi.crossref.org/simpleTextQuery' target='_blank' rel='noopener'>doi.crossref.org/simpleTextQuery</a> that takes an unstructured reference or reference list — pasted as plain citation text, not structured fields — and returns the matching DOI for each item it can identify. A submission can hold up to 1,000 references, entered one per line or block, and the tool attempts to return exactly one best-match DOI per reference by default (an option to list all possible matches is available when a reference is ambiguous). No Crossref membership or account is required to use it, and there is no charge. The same underlying free-text matching is also exposed programmatically through the Crossref REST API's <code>query.bibliographic</code> parameter on the <code>/works</code> route (for example <code>api.crossref.org/works?query.bibliographic=your+citation+string</code>), which is the machine-actionable equivalent of pasting a citation into the web form — useful for batch reference-linking pipelines rather than one-off lookups.</p>
ISRCTN
<p>ISRCTN — originally an acronym for International Standard Randomised Controlled Trial Number, now used as the registry's own name — is a UK-based clinical study registry that assigns a permanent, unique identifier (an ISRCTN number) to a study at or before its start. A study qualifies as "ISRCTN-registered" when its investigator or sponsor has submitted the required minimum data set (design, intervention, population, primary/secondary outcomes, sponsor, funder) through isrctn.com, the entry has passed the registry's validation checks, and it has been assigned a permanent identifier in the format ISRCTN followed by an eight-digit number (for example, ISRCTN12345678). Unlike its original RCT-only scope, ISRCTN now accepts any study assessing the effect of a health intervention on a human population, including non-randomised interventional studies and some observational designs — the acronym is retained for historical/branding reasons but no longer describes the registry's actual scope.</p>
Study Identifier
The unique code a registry assigns to identify a specific research study — a clinical trial, systematic review, or other registered research project — as that study itself, distinct from an identifier assigned to one of its resulting outputs (a DOI), its underlying dataset, or an individual researcher (an ORCID iD). A study identifier's format, prefix, and issuing authority are registry-specific: ClinicalTrials.gov assigns 'NCT' numbers, the ISRCTN registry assigns 'ISRCTN' numbers, and PROSPERO assigns 'CRD42' numbers. A single study can carry more than one study identifier if it is registered, or cross-registered, in more than one registry.
ISSN
An eight-digit identifier (ISO 3297), formatted NNNN-NNNC with a modulus-11 check digit as the final character, assigned to a continuing resource's TITLE — a journal, magazine, newspaper, or other serial published indefinitely over time, in print or online — by a national ISSN Centre under the coordination of the ISSN International Centre (CIEPS) in Paris. An ISSN identifies the serial as a whole, not any individual article, issue, or volume within it, and each distinct medium of the same title (print vs. online) is assigned its own ISSN, linked together via an ISSN-L.
ORCID iD for NIH Senior/Key Personnel
The ORCID iD requirement for NIH Senior/Key Personnel means: every individual designated as Senior/Key Personnel on an NIH grant application — the Program Director/Principal Investigator (PD/PI) plus any other individual who contributes to the scientific development or execution of a project in a substantive, measurable way, regardless of whether they receive salary support from the award — must (1) hold a registered ORCID iD, (2) link it to their own eRA Commons Personal Profile account, an action NIH requires the individual to complete themselves rather than delegate to grants administration staff, and (3) have that iD populate correctly in the Persistent Identifier (PID) field of the NIH Common Form versions of the Biographical Sketch and Current and Pending (Other) Support documents, both generated through SciENcv. This applies to applications with due dates on or after January 25, 2026 (NIH Guide Notice NOT-OD-26-018). An application missing a required, correctly linked ORCID iD for any listed Senior/Key Personnel is not merely flagged — as of May 8, 2026, eRA Commons system validations treat this as a hard error that blocks submission outright (NOT-OD-26-079), after an initial warning-only enforcement period (extended once, via NOT-OD-26-033, through May 7, 2026).
Australian Research Data Commons (ARDC)
The national research data infrastructure provider for Australia: a not-for-profit company, funded through the Australian Government's National Collaborative Research Infrastructure Strategy (NCRIS), that builds, operates, and stewards shared digital research infrastructure — including platforms, skills programs, and persistent-identifier services such as RAiD — for use across the Australian university and public-research sector rather than by any single institution.
Metadata enrichment
A record's metadata is enriched when new descriptive, administrative, or relational elements are added to it after initial deposit or harvest — typically by resolving free-text values (author names, affiliation strings, subject terms) against authority files and controlled vocabularies (ORCID, ROR, funder registries, subject-classification schemes), or by pulling additional attributes from an external API (citation counts, open-access status, computed topic classifications). It is distinct from correcting or normalizing values already present (data cleaning) and from the original act of depositing the baseline record (initial deposit) — enrichment specifically adds elements the record did not previously have.
Repository Citation
A repository citation is the reference used to attribute and locate a dataset (or other research output such as software or a physical sample) deposited in a data repository, built around a persistent identifier — typically a DOI minted via DataCite — rather than around the journal, volume, and page numbers used for an article citation. A citation counts as a repository citation when it points directly to the deposited data object itself (resolving through its own persistent identifier to the repository landing page or the data), not to a journal article, data paper, or other publication that merely describes or analyzes that data.
OSF Preprints
<p>A work counts as an <strong>OSF Preprints</strong> deposit if it is hosted on the preprint infrastructure built and operated by the <a href='https://www.cos.io' rel='nofollow'>Center for Open Science (COS)</a> -- either on the generalist osf.io/preprints server itself, or on one of the branded, discipline-specific community servers (PsyArXiv, SocArXiv, EarthArXiv, and others) that run on the same underlying OSF backend but carry their own name, editorial moderators, and disciplinary scope. It is distinct from an OSF <em>project</em> (the private/public research-management workspace) and from OSF Registries (preregistrations): a preprint is a discrete, versioned, publicly posted manuscript that receives its own Crossref-registered DOI, separate from any OSF project it may have originated in.</p>
ORCID Featured Works
A record is using ORCID Featured Works when the iD holder has designated one or more of their public works (up to a maximum of five) to appear in a dedicated "Featured" section at the top of the Works list on their ORCID record, each marked with a star icon. Featuring is a curation layer applied on top of an already-public work: only works whose visibility is already set to "Everyone" are eligible to be featured, and a work is automatically removed from the Featured list the moment its visibility is changed away from public. As of verification, the feature applies to the Works section only — there is no equivalent "Featured" mechanic for Employment, Education, Funding, Peer Review, or Distinctions entries on the record.
Persistent Identifier (PID)
A unique, actionable, long-term identifier assigned to a single entity in the research ecosystem -- a work, a person, an organisation, a piece of equipment, a project, or a dataset -- that is registered with a scheme-specific provider, stays associated with that entity even as its location or attributes change, resolves (typically over HTTP) to current metadata or the resource itself, and is designed to remain valid for decades, well beyond the lifetime of any one repository, publisher, or institutional system.
Metadata Schema
A defined, published set of descriptive fields (elements or properties) — each with a name, definition, expected data type or controlled vocabulary, and obligation/cardinality rules — used to describe a resource consistently enough for people and systems to find, cite, exchange, and reuse it. Distinct from a metadata record, which is one specific instance of data filled into that specification.
Researcher Identifier
A persistent, unique digital identifier assigned to an individual person -- as distinct from an identifier for a work, an institution, or a grant -- that disambiguates that researcher across name variants, career moves, and multiple scholarly systems, and that is designed to stay resolvable and machine-readable for the researcher's whole career.
Scopus Author ID
A Scopus Author ID is a numeric identifier that Elsevier's Scopus database automatically generates and attaches to a researcher's profile once that researcher has two or more documents indexed in Scopus — it is algorithmically assigned from article metadata (name variants, affiliation, subject area, co-authors, citation patterns), not requested or self-registered by the researcher, and a given person can end up with more than one Scopus Author ID if the algorithm fails to match all of their work to a single profile.
ClinicalTrials.gov
ClinicalTrials.gov is the NLM-operated (NIH, with FDA) public registry and results database for clinical studies, distinguished from clinical trial registration generally by being the specific U.S. system launched in 2000 (FDAMA Sec. 113) whose mandatory-registration and results-reporting requirements were established by the FDAAA 801 final rule (effective 18 January 2017), and which assigns every registered study a unique NCT identifier.
Journal Registration (ISSN Registration)
Journal registration is the process of obtaining an International Standard Serial Number (ISSN) for a serial publication -- an 8-digit identifier assigned exclusively by the ISSN Network (a national ISSN Centre, or the ISSN International Centre for countries without one) that uniquely identifies a specific title in a specific medium. A publication counts as "registered" only once the relevant Centre has verified the title, publisher, and format and formally assigned it an ISSN through the ISSN Portal -- not merely because a publisher claims or advertises one. It is a bibliographic-identification step, distinct from peer-review vetting, DOAJ inclusion, database indexing, or any copyright/trademark filing.
ResearcherID
ResearcherID is Clarivate's proprietary author identifier for the Web of Science ecosystem: a unique alphanumeric code (format letter(s)-numbers-year) assigned when a researcher creates a Web of Science Researcher Profile, used to disambiguate that person's publications and citation metrics within Web of Science and InCites. Since Clarivate retired Publons as a separate product in April 2022, ResearcherID exists as the identifier component of the unified Web of Science Researcher Profile rather than a standalone product, and (once a researcher explicitly connects the two accounts) two-way syncs publications with a connected ORCID iD.
ORCID Sign-In / Authentication
ORCID sign-in ("Sign in with ORCID") is the OAuth 2.0/OpenID Connect process by which a third-party system (a journal, funder, or institutional platform) redirects a researcher to orcid.org to authenticate, then receives back an authenticated ORCID iD and, if broader scopes were requested and approved, an access token to read or write specific parts of the researcher's ORCID record. It is distinct from simply holding an ORCID iD: an iD is a registered identifier; signing in is the act of a specific external system verifying, at that moment, that the researcher controls it, and optionally being granted ongoing record access.
Google Scholar Citations profile
A self-created, self-curated author page on scholar.google.com that displays a researcher's publications alongside auto-updating citation count, h-index, and i10-index figures computed from Google Scholar's own web index, distinct from database-issued author records such as a Scopus Author ID or an ORCID iD.
RRID (Research Resource Identifier)
A string of the form RRID: followed by an accession number issued by an authoritative source database (the Antibody Registry for AB_ numbers, Cellosaurus for CVCL_ cell-line codes, MGI/ZFIN/RGD/IMSR for model organisms, or SciCrunch's own SCR_ registry for software and databases) that resolves, via the SciCrunch resolver or a compatible resolver such as n2t.net, to a single curated record describing exactly one research resource. Developed through FORCE11's Resource Identification Initiative and maintained via SciCrunch's Resource Identification Portal, an RRID exists specifically so a research resource used in a study's methods can be cited unambiguously and traced across the literature, the way a DOI identifies a publication or an ORCID iD identifies a researcher.
CrossMark
A Crossref member service in which a publisher embeds a button on a published item (its HTML landing page, PDF, and/or ePub) that a reader can click to check the item's current status directly from within the item itself, rather than having to separately search the publisher's site. Clicking the button opens a panel showing whether the record has been updated since original publication -- including a correction, retraction, expression of concern, or one of the other editorially significant update types Crossref's schema defines -- alongside supporting metadata such as key dates (submission, revision, acceptance), funder information, licence terms, handling editors, and peer-review information where the publisher has chosen to provide it. A publication only counts as CrossMark-enabled if its publisher has (a) registered a DOI-assigned update policy, (b) referenced that policy in the item's Crossref metadata record even when no update yet exists, and (c) implemented the button so the status check happens at the item, not just on a separate corrections page a reader would have to know to look for.
Researcher Profile Optimization Study (RPOS)
An in-progress Federal Demonstration Partnership (FDP) initiative, run under FDP's Open Government: Research Administration Data (OG:RAD) subcommittee, that surveys researchers and research-administration offices across FDP's member institutions to document how federally required researcher profile information -- biosketches, current & pending support, and collaborator disclosures -- is captured across agencies and platforms, and to recommend changes that reduce duplicate data entry and support interoperability, research security, and compliance.
NISO Institutional Identifier (I2)
A now-inactive NISO initiative (2008–2013) whose output, ANSI/NISO RP-17-2013, is a Recommended Practice for identifying organizations in the scholarly information supply chain. It did not define a new identifier syntax of its own; instead it specified how to apply the existing ISNI standard (ISO 27729) to institutions. The working group has not been active since publishing the Recommended Practice in 2013, and I2 has no ongoing registry of its own — in current research-infrastructure practice, ROR is the identifier institutions actually register for and that funders, publishers, and CRIS systems require.
Research Data Alliance (RDA)
The Research Data Alliance (RDA) is a global, community-driven organisation, launched in March 2013 by the European Commission, the US National Science Foundation, the US National Institute of Standards and Technology, and the Australian government, to build the social and technical infrastructure needed for open data sharing across disciplines, technologies, and national borders. RDA operates chiefly through two kinds of groups: time-bounded Working Groups, which typically run around 18 months and produce concrete, adoptable deliverables, and open-ended Interest Groups, which coordinate ongoing discussion, surveys, and less formal outputs across a topic area. Formally endorsed Working Group deliverables are published as RDA Recommendations; less formal outputs from any group type are published as Supporting Outputs. Something qualifies as "RDA" only when it refers to the organisation itself — its membership, governance (Council, Technical Advisory Board, Secretariat), plenaries, and working/interest-group structure — not to any single recommendation, schema, or standard an RDA group has produced, which are distinct, separately citable outputs.
ORCID service
An affiliation entry in an ORCID record documenting an ongoing donation of a researcher's time or expertise to an organization or community — board, committee, or editorial-board membership, review panels, or extension work — captured with a role title, disambiguated organization identifier, and start/end dates.
ORCID invited position
An affiliation item in an ORCID record asserting that the iD holder holds or held a paid or unpaid invited role — such as a visiting lectureship, honorary or guest-researcher appointment, or emeritus professorship — at a named organisation, as distinct from an ordinary employment relationship. Captured with the organisation's name and disambiguated identifier (typically a ROR ID), department, role/title, start date, and optional end date. In the ORCID record schema and API, "invited-position" is one of seven distinct affiliation-type values (alongside employment, education, qualification, distinction, membership, and service) — it is a role the person actually holds, not merely an honour received (that is "distinction") and not professional service such as board or committee work (that is "service"), even though ORCID's own web entry form groups invited position and distinction into one combined section.
Pending publication (Crossref)
A Crossref record type that lets a publisher (a Crossref member) register a DOI and a minimal metadata record -- at minimum the member name, journal title, and the manuscript's accepted date -- for a manuscript that has already cleared peer review and received a formal editorial acceptance decision, but has not yet been published online. Until the work is formally published, the DOI resolves to a Crossref-hosted landing page carrying an acceptance notice and the deposited metadata, not to the article itself. The publisher must later update that same DOI's metadata record to a full journal-article registration once the work is published; only then does the DOI resolve directly to the published content. A record qualifies as a pending publication only if it was deposited by the eventual publisher for an already-accepted manuscript -- an unrefereed preprint, or a manuscript still under review, does not qualify.
Persistent data identifier
A persistent identifier (typically a DataCite DOI, but also IGSN for samples, Handle, ARK, or other PID-scheme identifier) assigned to a research dataset to support stable citation, attribution, and resolution over the long term.
Identifier crosswalk
A mapping or correspondence table between identifiers in different schemes that refer to the same real-world entity, allowing a system holding one scheme's identifier to find the equivalent identifier in another scheme.
DOI tombstone
A tombstone page served at the resolved URL of a DOI after the underlying resource has been withdrawn, providing withdrawal information and metadata while ensuring the DOI itself continues to resolve.
DOI suffix
The portion of a DOI after the first forward slash, assigned by the registrant within their issued DOI prefix, identifying the specific object; can contain any Unicode characters with the case-insensitivity rule applied during comparison.
DOI prefix
The leading portion of a DOI before the first forward slash, of the form 10.NNNN where 10 is the directory indicator for DOI under the Handle System and NNNN is a numeric (or alphanumeric) string assigned by the DOI Registration Agency to a specific registrant.
Tombstone page
A landing page served at a persistent identifier's resolved URL after the underlying resource has been withdrawn, retracted, or made permanently unavailable, providing metadata describing the former resource, the reason for its absence, and (where applicable) a successor identifier.
Identifier syntax
The formal grammar that constrains the textual form of identifiers in a given scheme — what character sets, lengths, prefixes, separators, and check digits are allowed — typically expressed as a regular expression or BNF grammar in the scheme's specification.
Identifier scheme
A named, formally-defined system for constructing, issuing, and resolving identifiers, typically defined by a syntax, an authority structure (who can mint), a metadata schema, and a resolution policy.
PID resolution
The process by which a persistent identifier is looked up through its scheme's resolution infrastructure and returned either as an HTTP redirect to the current resource location or as metadata about the resource, depending on the request and the scheme's policy.
PID minting
The act of generating a new persistent identifier in a registered scheme and registering it, with associated metadata, at the appropriate PID provider so that it becomes resolvable and discoverable.
PID metadata
The descriptive metadata registered with a PID provider at the time of identifier minting, and updated thereafter, that describes the identified entity — its title, creators, dates, types, related identifiers, and so on — and that is exposed by the provider's APIs alongside the identifier itself.
Funder ID
An identifier from the Crossref Funder Registry (formerly FundRef), a curated, open registry of funder names and identifiers used by publishers to tag deposited works with the funders that supported them.
Curated org record (ROR)
An entry in the ROR registry that has been reviewed and approved by ROR curators against the published inclusion criteria, carrying a stable ROR ID and metadata including names, types, country, geographic location, parent/child/related/successor/predecessor relationships, and crosswalks.
ROR Curation
The community-driven process by which the Research Organization Registry receives, reviews, and acts on requests to add new organisations, update existing records, merge duplicates, or split records, governed by a published curation policy and managed by ROR's curation team.
PID graph
A graph data structure in which persistent identifiers (ORCID iDs, DOIs, ROR IDs, RAiDs, IGSNs, etc.) are nodes and the metadata relationships among them (creator-of, affiliated-with, funded-by, derived-from) are edges, allowing federated queries across multiple PID-provider registries.
PID consortium
A grouping of PID-provider member organisations, typically at national or regional scale, formed to share infrastructure, contracts, and support around one or more persistent identifier schemes such as DOI, ORCID, or ROR.
PID provider
An organisation that issues persistent identifiers from one or more PID schemes, operates (or contracts) the resolution infrastructure for those identifiers, and makes long-term commitments about the maintenance of the identifiers and their metadata.
Resolution service
A networked service that, given a persistent identifier, returns the current location of the named resource (typically by HTTP redirect) or returns its metadata, allowing the identifier itself to remain stable while the resource's location changes.
Persistent URL
An HTTP(S) URL that an issuing organisation commits to maintain unchanged over time so that links continue to resolve correctly even as the underlying resource is moved, renamed, or migrated between systems.
w3id.org PURL
A persistent URL hosted on the w3id.org domain by the W3C Permanent Identifier Community Group, providing a community-maintained redirect under https://w3id.org/<namespace> to ontologies, vocabularies, and standards documents that may move between hosting providers over time.
PURL
Persistent Uniform Resource Locator, a URL maintained by a PURL service that redirects (typically via HTTP 302) to the current location of the named resource, allowing the persistent URL to remain stable as the underlying resource location changes.
URN
Uniform Resource Name (RFC 8141), a URI of the form urn:NID:NSS where NID is a registered Namespace Identifier and NSS is the namespace-specific string, intended to denote a resource persistently and independently of any particular resolution mechanism.
Handle
An identifier in the CNRI Handle System (RFC 3650-3652), of the form Prefix/Suffix (e.g. 20.500.12345/abcd), resolved by a distributed system of Handle servers that map the identifier to one or more current URLs or other typed data values.
ARK inflection rules
A convention of the ARK identifier scheme whereby appending a single '?' to an ARK URL yields the object's descriptive metadata and appending '??' yields a 'commitment statement' describing the issuing institution's persistence policy for that ARK.
ARK
Archival Resource Key, a persistent identifier scheme for information objects of any type, in the form ark:/NAAN/Name[Qualifier], where NAAN is a Name Assigning Authority Number and Name is the local identifier; resolvable through any cooperating ARK resolver.
UUID
Universally Unique Identifier (RFC 4122 / ISO/IEC 9834-8), a 128-bit value rendered as 32 hexadecimal digits in 8-4-4-4-12 grouping, generated such that the probability of collision across independent generators is negligible.
GUID
Globally Unique Identifier, a generic term for an identifier that is intended to be unique across all systems and time, most commonly implemented as a 128-bit UUID but used informally for any opaque, globally scoped identifier.
PIDINST
A persistent identifier for a research instrument, minted under a DataCite DOI or Handle, conforming to the PIDINST metadata schema developed by an RDA Working Group, that enables citation of and provenance back to the instrument that produced data.
IGSN
International Geo Sample Number, a globally unique persistent identifier for physical samples (geological, environmental, biological) that supports tracking and citation of the sample through subsequent analyses, publications, and derived data.
RAiD
Research Activity Identifier, an ISO-standardised persistent identifier (ISO 23527) for a research project or activity, providing a stable handle around which related people, organisations, outputs, instruments, and funding can be linked over the activity's lifetime.
DataCite consortium
A national or regional grouping of DataCite member organisations led by a 'Consortium Lead' that holds the master agreement with DataCite, allowing member institutions to mint DOIs under a shared fee structure and shared support model.
DataCite DOI
A DOI registered through DataCite, the DOI Registration Agency that serves research data, software, samples, dissertations, instruments, and other non-article research outputs, accompanied by metadata in the DataCite Metadata Schema.
Crossref DOI
A DOI registered through Crossref, the DOI Registration Agency for scholarly publications (journals, books, conference proceedings, preprints, peer reviews, grants), accompanied by metadata deposited in Crossref's XML schema.
DOI
Digital Object Identifier (ISO 26324), a persistent identifier for an entity (typically a research output) consisting of a prefix assigned to a registrant by a DOI Registration Agency and a suffix assigned by the registrant, resolvable as an HTTPS URI under https://doi.org/.
ISNI
International Standard Name Identifier (ISO 27729), a 16-digit identifier for the public identity of a person or organisation involved in the creation, production, management, or distribution of content, administered by the ISNI International Agency.
GRID
Global Research Identifier Database, a legacy identifier and registry of research organisations originally operated by Digital Science, frozen to new records in 2021 and superseded by ROR, which seeded its registry from a deduplicated GRID snapshot.
ROR ID
A persistent identifier for research organisations issued by the Research Organization Registry (ROR), expressed as an HTTPS URI of the form https://ror.org/0xxxxxxxx where the final nine-character path component is a base32-encoded random value with a check digit.
ORCID education
An affiliation item in an ORCID record asserting that the iD holder studied at a named organisation, including degree or qualification, department, start and end dates, and the organisation's disambiguated identifier.
ORCID employment
An affiliation item in an ORCID record asserting that the iD holder is or was employed by a named organisation, with start date, optional end date, department, role title, and the organisation's disambiguated identifier (typically a ROR ID).
ORCID work assertion
A claim, recorded in an ORCID record, that a particular research output (journal article, book chapter, dataset, software, etc.) is associated with the iD holder, with metadata fields including title, type, publication year, external identifiers (DOI, ISBN, PMID), and contributor role.
ORCID record permissions
The three-level visibility setting attached to each item in an ORCID record — public, trusted parties only (limited), or private — which the record holder applies individually to names, employments, works, fundings, and other assertions.
ORCID consortium
A national or regional grouping of ORCID member organisations that share a single membership fee structure and a lead organisation, in order to coordinate ORCID adoption, training, and policy advocacy within a country or region.
ORCID API
The two-tier REST application programming interface (Public API and Member API) operated by ORCID that allows systems to read public ORCID record data and, with researcher authorisation, to read restricted data or write trusted-party assertions to records.
ORCID record
The structured profile maintained at orcid.org for an individual ORCID iD, containing assertions about the person's names, employments, educations, funding, works, peer reviews, and service activities, each with a visibility setting and a source attribution.
ORCID iD
A 16-digit persistent identifier, expressed as four hyphen-separated blocks (e.g. 0000-0002-1825-0097) and resolvable as an HTTPS URI under https://orcid.org/, that uniquely identifies an individual researcher across publications, datasets, grants, employments, and peer-review activity.
