Identifier
name that identifies either a unique object or a unique class of objects
An identifier is a name that identifies (that is, labels the identity of) either a unique class of objects or a unique instance of such objects; the class or instance may be an idea, person, physical countable object (or class thereof), or physical noncountable substance (or class thereof). The abbreviation "ID" may refer to identity, identification (the process of identifying), or an identifier (that is, an instance of identification).
An identifier may be a word, number, letter, symbol, or any combination of those. If the identifier follows an encoding system—wherein parts of the identifier stand for [represent] ideas or longer names—it is often referred to as a code or ID code. Identifiers that do not follow any encoding scheme are often said to be arbitrary IDs as they have no greater meaning.
A unique identifier (UID) is an identifier that refers to only one instance—only one particular object in the universe. A part number is an identifier, but it is not a unique identifier—for that, a serial number would be needed, to identify each instance of the part design. For example, the identifier "Model T" identifies the class (or model) of automobiles that Ford's Model T comprises; whereas the unique identifier "Model T Serial Number 159,862" identifies one specific member of that class—that is, one particular Model T car, owned by one specific person.
Metadata
In metadata, an identifier is a language-independent label, sign or token that uniquely identifies an object within an identification scheme. The suffix "identifier" is also used as a representation term when naming a data element.
This brief starts where responsible research should: with the source description of “Identifier” as name that identifies either a unique object or a unique class of objects. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the general reference register because the source frames it as name that identifies either a unique object or a unique class of objects. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Jul 25, 2026. The linked authority identifier is Q853614. None of the 0 selected statements returned an explicit reference.
A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Identifier”, its source revision and the description used here.
- Expand the search: follow Identifier primary sources, Identifier archive and Identifier research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Identifier”?
- Which institution is responsible for the underlying evidence?
- Which cited source is closest to the event, object or claim?
Search terms from this dossier
This entry incorporates text from “Identifier” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.