CACrown ArchivesThe cinema collection
EN/FR
Search
Menu
Research dossier · General Reference

Value type and reference type

Wikipedia article covering multiple topics

Cross-disciplinary reference desk with index cards, atlas, dictionary and catalogue
General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionMar 7, 2026
Entity authorityQ59627259 ↗
Source-derived summary

In certain computer programming languages, data types are classified as either value types or reference types, where values referenced by reference type variables are always implicitly accessed via references stored in those variables, whereas value type variables directly contain the values themselves.

Properties of value types and reference types

Even among languages that have this distinction, the exact properties of value and reference types vary from language to language, but typical properties include:

Primitive data types, such as Booleans, fixed-size integers, floating-point values, and characters, are value types.

Objects, in the sense of object-oriented programming, belong to reference types.

Assigning to a variable of reference type simply copies the reference, whereas assigning to a variable of value type copies the value. This applies to all kinds of variables, including local variables, fields of objects, and array elements. Likewise when calling a function: parameters of reference type are copies of the reference, whereas parameters of value type are copies of the value.

If a reference type is mutable, then mutations made via one reference are visible via any other, whereas if a value type is immutable, then mutations made to one value are not visible in another.

Reference types support the notion of identity — it makes sense to discuss whether two values of reference type refer to the same object, and the language provides functionality to determine whether they do — whereas value types do not.

Values of reference type refer to objects allocated in the heap, whereas values of value type are contained either on the call stack (in the case of local variables and function parameters) or inside their containing entities (in the case of fields of objects and array elements). (With reference types, it is only the reference itself that is contained either on the call stack or inside a containing entity.)

Reference types support the notion of subtyping, whereby all values of a given reference type are automatically values of a different reference type.

Editorial summary

This brief starts where responsible research should: with the source description of “Value type and reference type” as wikipedia article covering multiple topics. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current 328-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. The account is most persuasive where Value, type and Wikipedia can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as wikipedia article covering multiple topics. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Mar 7, 2026. The linked authority identifier is Q59627259. None of the 0 selected statements returned an explicit reference.

Critical limits

Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. 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.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “Value type and reference type”, its source revision and the description used here.
  2. Expand the search: follow Value type and reference type primary sources, Value type and reference type archive and Value research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “Value type and reference type”?
  2. What terminology or title could unlock a more precise catalogue search?
  3. Which cited source is closest to the event, object or claim?
Subject index

Search terms from this dossier

Source & attribution

This entry incorporates text from “Value type and reference type” 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.