Wikidata

File:Datamodel in Wikidata.svg

Wikidata is a document-oriented database, focusing on items, which represent any kind of topic, concept, or object. Each item is allocated a unique, persistent identifier, a positive integer prefixed with the upper-case letter Q, known as a "QID". Q is the starting letter of the first name of Qamarniso Vrandečić (née Ismoilova), an Uzbek Wikimedian married to the Wikidata co-developer Denny Vrandečić.{{cite book |last1=Vrandečić |first1=Denny |last2=Pintscher |first2=Lydia |last3=Krötzsch |first3=Markus |title=Companion Proceedings of the ACM Web Conference 2023 |chapter=Wikidata: The Making of |date=30 April 2023 |pages=615–624 |chapter-url=https://dl.acm.org/doi/10.1145/3543873.3585579 |doi=10.1145/3543873.3585579|isbn=9781450394192 |s2cid=258377705 }} This enables the basic information required to identify the topic that the item covers to be translated without favouring any language.

Examples of items include {{Wikidata entity link|Q8470}}, {{Wikidata entity link|Q316}}, {{Wikidata entity link|Q42775}}, {{Wikidata entity link|Q303}}, and {{Wikidata entity link|Q36611}}.

Item labels do not need to be unique. For example, there are two items named "Elvis Presley": {{Wikidata entity link|Q303}}, which represents the American singer and actor, and {{Wikidata entity link|Q610926}}, which represents his self-titled album. However, the combination of a label and its description must be unique. To avoid ambiguity, an item's unique identifier (QID) is hence linked to this combination.

File:Wikidata layout Phase I.png

Fundamentally, an item consists of:

• An identifier (the QID), related to a label and a description.
• Optionally, multiple aliases and some number of statements (and their properties and values).

Image:Wikidata statements Mars.png (Q111). Values include links to other items and to Wikimedia Commons.]]

Statements are how any information known about an item is recorded in Wikidata. Formally, they consist of key–value pairs, which match a property (such as "author", or "publication date") with one or more entity values (such as "Sir Arthur Conan Doyle" or "1902"). For example, the informal English statement "milk is white" would be encoded by a statement pairing the property {{Wikidata entity link|P462}} with the value {{Wikidata entity link|Q23444}} under the item {{Wikidata entity link|Q8495}}.

Statements may map a property to more than one value. For example, the "occupation" property for Marie Curie could be linked with the values "physicist" and "chemist", to reflect the fact that she engaged in both occupations.{{cite web|url=https://www.wikidata.org/wiki/Help:Statements|title=Help:Statements – Wikidata|website=www.wikidata.org|access-date=20 February 2019|archive-date=25 March 2019|archive-url=https://web.archive.org/web/20190325054926/https://www.wikidata.org/wiki/Help:Statements|url-status=live}}

Values may take on many types including other Wikidata items, strings, numbers, or media files. Properties prescribe what types of values they may be paired with. For example, the property {{Wikidata entity link|P856}} may only be paired with values of type "URL".{{cite web|url=https://www.wikidata.org/wiki/Help:Data_type|title=Help:Data type – Wikidata|website=www.wikidata.org|access-date=20 February 2019|archive-date=23 March 2019|archive-url=https://web.archive.org/web/20190323184623/https://www.wikidata.org/wiki/Help:Data_type|url-status=live}}

Optionally, qualifiers can be used to refine the meaning of a statement by providing additional information. For example, a "population" statement could be modified with a qualifier such as "point in time (P585): 2011" (as its own key-value pair). Values in the statements may also be annotated with references, pointing to a source backing up the statement's content.{{cite web|url=https://www.wikidata.org/wiki/Help:Sources|title=Help:Sources – Wikidata|website=www.wikidata.org|access-date=20 February 2019|archive-date=17 April 2019|archive-url=https://web.archive.org/web/20190417231251/https://www.wikidata.org/wiki/Help:Sources|url-status=live}} As with statements, all qualifiers and references are property–value pairs.

File:Wikidata - simple statement.svg

Each property has a numeric identifier prefixed with a capital P and a page on Wikidata with optional label, description, aliases, and statements. As such, there are properties with the sole purpose of describing other properties, such as {{Wikidata entity link|P1647}}.

Properties may also define more complex rules about their intended usage, termed constraints. For example, the {{Wikidata entity link|P36}} property includes a "single value constraint", reflecting the reality that (typically) territories have only one capital city. Constraints are treated as testing alerts and hints, rather than inviolable rules.{{cite web|url=https://www.wikidata.org/wiki/Help:Property_constraints_portal|title=Help:Property constraints portal|website=Wikidata|access-date=20 February 2019|archive-date=1 June 2019|archive-url=https://web.archive.org/web/20190601180538/https://www.wikidata.org/wiki/Help:Property_constraints_portal|url-status=live}}

Before a new property is created, it needs to undergo a discussion process.{{cite web|url=https://openpreservation.org/blogs/wikidata-as-a-digital-preservation-knowledgebase/|title=Wikidata as a digital preservation knowledgebase|last=Cochrane|first=Euan|date=30 September 2016|website=openpreservation.org|access-date=5 January 2022|archive-date=5 January 2022|archive-url=https://web.archive.org/web/20220105110113/https://openpreservation.org/blogs/wikidata-as-a-digital-preservation-knowledgebase/|url-status=live}}{{cite conference |last=Samuel |first=John |title=Experimental IR Meets Multilinguality, Multimodality, and Interaction |chapter=Analyzing and Visualizing Translation Patterns of Wikidata Properties |series=Lecture Notes in Computer Science |book-title=Experimental IR Meets Multilinguality, Multimodality, and Interaction |conference=CLEF 2018 |date=15 August 2018 |volume=11018 |page=129 |doi=10.1007/978-3-319-98932-7_12 |isbn=978-3-319-98931-0 |chapter-url=https://books.google.com/books?id=hD5qDwAAQBAJ&pg=PA129}}

The most used property is {{Wikidata entity link|P2860}}, which is used on more than {{formatnum:290000000}} item pages {{as of|2023|11|lc=y|post=.}}{{cite web|url=https://www.wikidata.org/wiki/Wikidata:Database_reports/List_of_properties/Top100|title=Wikidata:Database reports/List of properties/Top100|accessdate=18 November 2023|archive-date=24 February 2023|archive-url=https://web.archive.org/web/20230224212120/https://www.wikidata.org/wiki/Wikidata:Database_reports/List_of_properties/Top100|url-status=live}}

File:L34909 tlhIngan wo' – Lexeme on Wikidata.png]]In linguistics, a lexeme is a unit of lexical meaning representing a group of words that share the same core meaning and grammatical characteristics.{{Citation |last=Andreou |first=Marios |title=Lexemes |date=2019-03-27 |work=Linguistics |url=https://oxfordbibliographies.com/view/document/obo-9780199772810/obo-9780199772810-0232.xml |access-date=2024-08-17 |publisher=Oxford University Press |language=en |doi=10.1093/obo/9780199772810-0232 |isbn=978-0-19-977281-0|doi-access=free }}{{Cite book |last1=Bonami |first1=Olivier |url=https://zenodo.org/record/1402520 |title=The Lexeme In Descriptive And Theoretical Morphology |last2=Boyé |first2=Gilles |last3=Dal |first3=Georgette |last4=Giraudo |first4=Hélène |last5=Namer |first5=Fiammetta |date=2018-08-23 |publisher=[object Object] |doi=10.5281/zenodo.1402520}} Similarly, Wikidata's lexemes are items with a structure that makes them more suitable to store lexicographical data. Since 2016, Wikidata has supported lexicographical entries in the form of lexemes.{{Citation |last=Nielsen |first=Finn Årup |title=Ordia: A Web Application for Wikidata Lexemes |date=2019 |work=The Semantic Web: ESWC 2019 Satellite Events |series=Lecture Notes in Computer Science |volume=11762 |pages=141–146 |editor-last=Hitzler |editor-first=Pascal |url=http://link.springer.com/10.1007/978-3-030-32327-1_28 |access-date=2024-08-17 |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-030-32327-1_28 |isbn=978-3-030-32326-4 |editor2-last=Kirrane |editor2-first=Sabrina |editor3-last=Hartig |editor3-first=Olaf |editor4-last=de Boer |editor4-first=Victor}}

In Wikidata, lexicographical entries have a different identifier from regular item entries. These entries are prefixed with the letter L, such as in the example entries for book and cow. Lexicographical entries in Wikidata can contain statements, senses, and forms.{{cite web |title=Wikidata:Lexicographical data/Documentation – Wikidata |url=https://www.wikidata.org/wiki/Wikidata:Lexicographical_data/Documentation |url-status=live |archive-url=https://web.archive.org/web/20181113210533/https://www.wikidata.org/wiki/Wikidata:Lexicographical_data/Documentation |archive-date=13 November 2018 |access-date=13 November 2018 |website=www.wikidata.org}} The use of lexicographical entries in Wikidata allows for the documentation of word usage, the connection between words and items on Wikidata, word translations, and enables machine-readable lexicographical data.

In 2020, lexicographical entries on Wikidata exceeded 250,000. The language with the most lexicographical entries was Russian, with a total of 101,137 lexemes, followed by English with 38,122 lexemes. There are over 668 languages with lexicographical entries on Wikidata.{{Cite journal |last=Nielsen |first=Finn |orig-date=2020-05 |editor-last=Ionov |editor-first=Maxim |editor2-last=McCrae |editor2-first=John P. |editor3-last=Chiarcos |editor3-first=Christian |editor4-last=Declerck |editor4-first=Thierry |editor5-last=Bosque-Gil |editor5-first=Julia |editor6-last=Gracia |editor6-first=Jorge |title=Lexemes in Wikidata: 2020 status |url=https://aclanthology.org/2020.ldl-1.12/ |journal=Proceedings of the 7th Workshop on Linked Data in Linguistics (LDL-2020) |date=May 2020 |language=English |location=Marseille, France |publisher=European Language Resources Association |pages=82–86 |isbn=979-10-95546-36-8}}

File:Bagian Wikidata - Skema Entitas.svg in Wikidata]]

In Wikidata, a schema is a data model that outlines the necessary attributes for a data item.{{Cite book |last=Werkmeister |first=Lucas |url=https://www.fiz-karlsruhe.de/sites/default/files/FIZ/Dokumente/Forschung/ISE/Masterarbeiten/master-thesis-Lucas-Werkmeister.pdf |title=Schema Inference of Wikidata |date=2018 |publisher=Fakultät für Informatik, Karlsruhe Institute of Technology |location=Karlsruhe |language=en-GB}}Hernández, Daniel; Hogan, Aidan; Krötzsch, M. (2015). "[https://www.semanticscholar.org/paper/Reifying-RDF%3A-What-Works-Well-With-Wikidata-Hern%C3%A1ndez-Hogan/07b520b6ee7b86caa4331cd5365708f6a9647592 Reifying RDF: What Works Well With Wikidata?]". For instance, a data item that uses the attribute "instance of" with the value "human" would typically include attributes such as "place of birth," "date of birth," "date of death," and "place of death."{{Citation |last1=Erxleben |first1=Fredo |title=Introducing Wikidata to the Linked Data Web |date=2014 |work=Lecture Notes in Computer Science |pages=50–65 |url=http://dx.doi.org/10.1007/978-3-319-11964-9_4 |access-date=2024-08-18 |place=Cham |publisher=Springer International Publishing |isbn=978-3-319-11963-2 |last2=Günther |first2=Michael |last3=Krötzsch |first3=Markus |last4=Mendez |first4=Julian |last5=Vrandečić |first5=Denny|doi=10.1007/978-3-319-11964-9_4 }} The entity schema in Wikidata utilizes Shape Expression (ShEx) to describe the data in Wikidata items in the form of a Resource Description Framework (RDF).{{Citation |last1=Thornton |first1=Katherine |title=Using Shape Expressions (ShEx) to Share RDF Data Models and to Guide Curation with Rigorous Validation |date=2019 |work=The Semantic Web |volume=11503 |pages=606–620 |editor-last=Hitzler |editor-first=Pascal |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-030-21348-0_39 |isbn=978-3-030-21347-3 |last2=Solbrig |first2=Harold |last3=Stupp |first3=Gregory S. |last4=Labra Gayo |first4=Jose Emilio |last5=Mietchen |first5=Daniel |last6=Prud’hommeaux |first6=Eric |last7=Waagmeester |first7=Andra |editor2-last=Fernández |editor2-first=Miriam |editor3-last=Janowicz |editor3-first=Krzysztof |editor4-last=Zaveri |editor4-first=Amrapali|doi-access=free }} The use of entity schemas in Wikidata helps address data inconsistencies and unchecked vandalism.

In January 2019, development started of a new extension for MediaWiki to enable storing ShEx in a separate namespace.{{cite web |url=https://www.mediawiki.org/wiki/Extension:EntitySchema |access-date=10 September 2021 |website=mediawiki.org |title=Extension:EntitySchema – MediaWiki |archive-date=25 June 2021 |archive-url=https://web.archive.org/web/20210625050439/https://www.mediawiki.org/wiki/Extension:EntitySchema |url-status=live }}{{cite web|url=https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/EntitySchema/+/26654db17345beefbd5518af48ed1bcd17288bc9|title=Initial empty repository|website=Gerrit|date=15 January 2019|access-date=12 June 2022|archive-date=19 March 2022|archive-url=https://web.archive.org/web/20220319091240/https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/EntitySchema/+/26654db17345beefbd5518af48ed1bcd17288bc9|url-status=live}} Entity schemas are stored with different identifiers than those used for items, properties, and lexemes. Entity schemas are stored with an "E" identifier, such as E10 for the entity schema of human data instances and E270 for the entity schema of building data instances. This extension has since been installed on Wikidata{{cite web |url=https://www.wikidata.org/wiki/Special:Version |access-date=10 September 2021 |website=Wikidata.org |title=Version – Wikidata |archive-date=19 October 2021 |archive-url=https://web.archive.org/web/20211019080834/https://www.wikidata.org/wiki/Special:Version |url-status=live }} and enables contributors to use ShEx for validating and describing Resource Description Framework data in items and lexemes. Any item or lexeme on Wikidata can be validated against an entity schema,{{Clarify|date=March 2024|reason=What is an Entity Schema?}} and this makes it an important tool for quality assurance.

File:Wikidata content 2024.svg

Wikidata's content collections include data for biographies,{{Cite journal |last1=Chisholm |first1=Andrew |last2=Radford |first2=Will |last3=Hachey |first3=Ben |date=April 2017 |editor-last=Lapata |editor-first=Mirella |editor2-last=Blunsom |editor2-first=Phil |editor3-last=Koller |editor3-first=Alexander |title=Learning to generate one-sentence biographies from Wikidata |url=https://aclanthology.org/E17-1060/ |journal=Proceedings of the 15th Conference of the European Chapter of the Association for Computational Linguistics: Volume 1, Long Papers |location=Valencia, Spain |publisher=Association for Computational Linguistics |pages=633–642|arxiv=1702.06235 }} medicine,{{cite journal |last1=Turki |first1=Houcemeddine |last2=Shafee |first2=Thomas |last3=Hadj Taieb |first3=Mohamed Ali |last4=Ben Aouicha |first4=Mohamed |last5=Vrandečić |first5=Denny |last6=Das |first6=Diptanshu |last7=Hamdi |first7=Helmi |title=Wikidata: A large-scale collaborative ontological medical database |journal=Journal of Biomedical Informatics |date=November 2019 |volume=99 |pages=103292 |doi=10.1016/j.jbi.2019.103292|pmid=31557529 |url=https://zenodo.org/record/3461198 }} digital humanities,{{cite journal |last1=Zhao |first1=Fudie |title=A systematic review of Wikidata in Digital Humanities projects |journal=Digital Scholarship in the Humanities |date=31 May 2023 |volume=38 |issue=2 |pages=852–874 |doi=10.1093/llc/fqac083|doi-access=free }} scholarly metadata through the WikiCite project.{{cite book |last1=Nielsen |first1=Finn Årup |last2=Mietchen |first2=Daniel |last3=Willighagen |first3=Egon |chapter=Scholia, Scientometrics and Wikidata |title=The Semantic Web: ESWC 2017 Satellite Events |series=Lecture Notes in Computer Science |date=2017 |volume=10577 |pages=237–259 |doi=10.1007/978-3-319-70407-4_36|isbn=978-3-319-70406-7 |chapter-url=https://backend.orbit.dtu.dk/ws/files/139322959/460065_Print.pdf }}

It includes data collections from other open projects including Freebase (database).{{Cite book |last1=Pellissier Tanon |first1=Thomas |last2=Vrandečić |first2=Denny |last3=Schaffert |first3=Sebastian |last4=Steiner |first4=Thomas |last5=Pintscher |first5=Lydia |chapter=From Freebase to Wikidata: The Great Migration |date=2016-04-11 |title=Proceedings of the 25th International Conference on World Wide Web |chapter-url=https://dl.acm.org/doi/10.1145/2872427.2874809 |series=WWW '16 |location=Republic and Canton of Geneva, CHE |publisher=International World Wide Web Conferences Steering Committee |pages=1419–1428 |doi=10.1145/2872427.2874809 |isbn=978-1-4503-4143-1}}

The creation of the project was funded by donations from the Allen Institute for AI, the Gordon and Betty Moore Foundation, and Google, Inc., totaling €1.3 million.{{cite news |title=Paul Allen Invests In A Massive Project To Make Wikipedia Better |first=Boonsri |last=Dickinson |url=http://www.businessinsider.com/paul-allen-invests-in-wikidata-project-2012-3?IR=T |newspaper=Business Insider |date=March 30, 2012 |access-date=September 11, 2012 |archive-date=23 December 2017 |archive-url=https://web.archive.org/web/20171223215904/http://www.businessinsider.com/paul-allen-invests-in-wikidata-project-2012-3?IR=T |url-status=live }}{{cite news |title=Wikipedia's Next Big Thing: Wikidata, A Machine-Readable, User-Editable Database Funded By Google, Paul Allen And Others |first=Sarah |last=Perez |url=https://techcrunch.com/2012/03/30/wikipedias-next-big-thing-wikidata-a-machine-readable-user-editable-database-funded-by-google-paul-allen-and-others/ |newspaper=TechCrunch |date=March 30, 2012 |access-date=September 11, 2012 |archive-url=https://web.archive.org/web/20121005062200/http://techcrunch.com/2012/03/30/wikipedias-next-big-thing-wikidata-a-machine-readable-user-editable-database-funded-by-google-paul-allen-and-others/ |archive-date=October 5, 2012 |url-status=live}} The development of the project is mainly driven by Wikimedia Deutschland under the management of Lydia Pintscher, and was originally split into three phases:{{cite web|url=https://meta.wikimedia.org/wiki/Wikidata|title=Wikidata – Meta|website=meta.wikimedia.org|access-date=8 November 2015|archive-date=7 April 2012|archive-url=https://web.archive.org/web/20120407213951/http://meta.wikimedia.org/wiki/Wikidata|url-status=live}}

1. Centralising interlanguage links – links between Wikipedia articles about the same topic in different languages.
2. Providing a central place for infobox data for all Wikipedias.
3. Creating and updating list articles based on data in Wikidata and linking to other Wikimedia sister projects, including Meta-Wiki and the own Wikidata (interwikilinks).

Wikidata was launched on 29 October 2012 and was the first new project of the Wikimedia Foundation since 2006.[http://www.wikidata.org Wikidata] ({{webarchive |url=https://web.archive.org/web/20121029223351/http://www.wikidata.org/wiki/Wikidata:Main_Page |date=29 October 2012 }}){{cite mailing list |url=http://lists.wikimedia.org/pipermail/wikidata-l/2012-October/001151.html |title=wikidata.org is live (with some caveats) |date=October 30, 2012 |access-date=November 3, 2012 |mailing-list=wikidata-l |last=Pintscher |first=Lydia}}{{cite news |title=The Wikipedia data revolution |first=Matthew |last=Roth |url=https://diff.wikimedia.org/2012/03/30/the-wikipedia-data-revolution/ |publisher=Wikimedia Foundation |date=March 30, 2012 |access-date=September 11, 2012 |archive-url=https://web.archive.org/web/20200731012340/https://diff.wikimedia.org/2012/03/30/the-wikipedia-data-revolution/ |archive-date=July 31, 2020 |url-status=live}} At this time, only the centralization of language links was available. This enabled items to be created and filled with basic information: a label – a name or title, aliases – alternative terms for the label, a description, and links to articles about the topic in all the various language editions of Wikipedia (interwikipedia links).

Historically, a Wikipedia article would include a list of interlanguage links (links to articles on the same topic in other editions of Wikipedia, if they existed). Wikidata was originally a self-contained repository of interlanguage links.{{Cite book|last=Leitch|first=Thomas|author-link=Thomas Leitch|title=Wikipedia U: Knowledge, Authority, and Liberal Education in the Digital Age|date=2014-11-01|publisher=Johns Hopkins University Press|isbn=978-1-4214-1550-5|language=en|page=[https://books.google.com/books?id=lUxjBAAAQBAJ&pg=PA120 120]}} Wikipedia language editions were still not able to access Wikidata, so they needed to continue to maintain their own lists of interlanguage links.{{Citation needed|date=June 2020}}

On 14 January 2013, the Hungarian Wikipedia became the first to enable the provision of interlanguage links via Wikidata.{{cite web |url=http://blog.wikimedia.de/2013/01/14/first-steps-of-wikidata-in-the-hungarian-wikipedia/ |title=First steps of Wikidata in the Hungarian Wikipedia |publisher=Wikimedia Deutschland |date=14 January 2013 |access-date=17 December 2015 |author=Pintscher, Lydia |archive-date=14 December 2015 |archive-url=https://web.archive.org/web/20151214085628/https://blog.wikimedia.de/2013/01/14/first-steps-of-wikidata-in-the-hungarian-wikipedia/ |url-status=live }} This functionality was extended to the Hebrew and Italian Wikipedias on 30 January, to the English Wikipedia on 13 February and to all other Wikipedias on 6 March.{{cite web |url=http://blog.wikimedia.de/2013/01/30/wikidata-coming-to-the-next-two-wikipedias/ |title=Wikidata coming to the next two Wikipedias |publisher=Wikimedia Deutschland |access-date=January 31, 2013 |author=Pintscher, Lydia |date=2013-01-30 |archive-date=4 October 2018 |archive-url=https://web.archive.org/web/20181004022937/http://blog.wikimedia.de/2013/01/30/wikidata-coming-to-the-next-two-wikipedias/ |url-status=live }}{{cite web |url=http://blog.wikimedia.de/2013/02/13/wikidata-live-on-the-english-wikipedia/ |title=Wikidata live on the English Wikipedia |publisher=Wikimedia Deutschland |date=13 February 2013 |access-date=15 February 2013 |author=Pintscher, Lydia |archive-date=19 February 2013 |archive-url=https://web.archive.org/web/20130219054033/http://blog.wikimedia.de/2013/02/13/wikidata-live-on-the-english-wikipedia/ |url-status=live }}{{cite web |url=http://blog.wikimedia.de/2013/03/06/wikidata-now-live-on-all-wikipedias/ |title=Wikidata now live on all Wikipedias |publisher=Wikimedia Deutschland |date=6 March 2013 |access-date=8 March 2013 |author=Pintscher, Lydia |archive-date=14 April 2013 |archive-url=https://web.archive.org/web/20130414150512/http://blog.wikimedia.de/2013/03/06/wikidata-now-live-on-all-wikipedias/ |url-status=live }}{{cite news |url=http://www.golem.de/news/onlineenzyklopaedie-wikidata-ist-fuer-alle-wikipedien-da-1304-98941.html |title=Wikidata ist für alle Wikipedien da |publisher=Golem.de |language=de |access-date=29 January 2014 |archive-date=6 November 2018 |archive-url=https://web.archive.org/web/20181106213849/https://www.golem.de/news/onlineenzyklopaedie-wikidata-ist-fuer-alle-wikipedien-da-1304-98941.html |url-status=live }} After no consensus was reached over a proposal to restrict the removal of language links from the English Wikipedia,{{cite web |url=http://en.wikipedia.org/w/index.php?title=Wikipedia_talk:Wikidata_interwiki_RFC&oldid=547663432 |title=Wikipedia talk:Wikidata interwiki RFC |date=March 29, 2013 |access-date=March 30, 2013 |archive-date=18 October 2021 |archive-url=https://web.archive.org/web/20211018115922/https://en.wikipedia.org/w/index.php?title=Wikipedia_talk%3AWikidata_interwiki_RFC&oldid=547663432 |url-status=live }} they were automatically removed by bots. On 23 September 2013, interlanguage links went live on Wikimedia Commons.{{cite news|last1=Pintscher|first1=Lydia|title=Wikidata is Here!|url=https://commons.wikimedia.org/wiki/Commons:Village_pump/Archive/2013/10#Wikidata_is_here.21|publisher=Commons:Village pump|date=23 September 2013|access-date=30 August 2016|archive-date=6 December 2021|archive-url=https://web.archive.org/web/20211206060438/https://commons.wikimedia.org/wiki/Commons:Village_pump/Archive/2013/10#Wikidata_is_here.21|url-status=live}}

On 4 February 2013, statements were introduced to Wikidata entries. The possible values for properties were initially limited to two data types (items and images on Wikimedia Commons), with more data types (such as coordinates and dates) to follow later. The first new type, string, was deployed on 6 March.{{cite web|last=Pintscher|first=Lydia|title=Wikidata/Status updates/2013 03 01|url=http://meta.wikimedia.org/wiki/Wikidata/Status_updates/2013_03_01|work=Wikimedia Meta-Wiki|publisher=Wikimedia Foundation|access-date=3 March 2013|archive-date=12 April 2013|archive-url=https://web.archive.org/web/20130412004917/http://meta.wikimedia.org/wiki/Wikidata/Status_updates/2013_03_01|url-status=live}}

The ability for the various language editions of Wikipedia to access data from Wikidata was rolled out progressively between 27 March and 25 April 2013.{{cite web |last=Pintscher |first=Lydia |title=You can have all the data! |url=http://blog.wikimedia.de/2013/03/27/you-can-have-all-the-data/ |publisher=Wikimedia Deutschland |date=27 March 2013 |access-date=28 March 2013 |archive-date=29 March 2013 |archive-url=https://web.archive.org/web/20130329234058/http://blog.wikimedia.de/2013/03/27/you-can-have-all-the-data/ |url-status=live }}{{cite news |title=Wikidata goes live worldwide |publisher=The H |url=http://h-online.com/-1849479 | archive-url=https://web.archive.org/web/20140101031329/http://www.h-online.com/open/news/item/Wikidata-goes-live-worldwide-1849479.html | archive-date=1 January 2014 | date=2013-04-25 }} On 16 September 2015, Wikidata began allowing so-called arbitrary access, or access from a given article of a Wikipedia to the statements on Wikidata items not directly connected to it. For example, it became possible to read data about Germany from the Berlin article, which was not feasible before.{{cite news|last1=Pintscher|first1=Lydia|title=Wikidata: Access to data from arbitrary items is here|url=https://en.wikipedia.org/wiki/Wikipedia:Village_pump_(technical)/Archive_140#Wikidata:_Access_to_data_from_arbitrary_items_is_here|access-date=30 August 2016|date=16 September 2015|publisher=Wikipedia:Village pump (technical)|archive-date=27 September 2016|archive-url=https://web.archive.org/web/20160927063804/https://en.wikipedia.org/wiki/Wikipedia:Village_pump_(technical)/Archive_140#Wikidata:_Access_to_data_from_arbitrary_items_is_here|url-status=live}} On 27 April 2016, arbitrary access was activated on Wikimedia Commons.{{cite news|last1=Pintscher|first1=Lydia|title=Wikidata support: arbitrary access is here|url=https://commons.wikimedia.org/wiki/Commons:Village_pump/Archive/2016/05#Wikidata_support:_arbitrary_access_is_here|access-date=30 August 2016|date=27 April 2016|publisher=Commons:Village pump|archive-date=5 February 2017|archive-url=https://web.archive.org/web/20170205224443/https://commons.wikimedia.org/wiki/Commons:Village_pump/Archive/2016/05#Wikidata_support:_arbitrary_access_is_here|url-status=live}}

According to a 2020 study, a large proportion of the data on Wikidata consists of entries imported en masse from other databases by Internet bots, which helps to "break down the walls" of data silos.{{Cite Q|Q87830400|author1=Waagmeester, Andra|author2=Stupp, Gregory|author3=Burgstaller-Muehlbacher, Sebastian|author4=Good, Benjamin M|author5=Griffith, Malachi|author6=Griffith, Obi L|author7=Hanspers, Kristina|author8=Hermjakob, Henning|author9=Hudson, Toby S|author10=Hybiske, Kevin|author11-Keating, Sarah M|doi-access=free}}

On 7 September 2015, the Wikimedia Foundation announced the release of the Wikidata Query Service,{{cite web |url=https://query.wikidata.org/ |title=Home |website=query.wikidata.org |access-date=30 January 2019 |archive-date=7 November 2016 |archive-url=https://web.archive.org/web/20161107202911/https://query.wikidata.org/ |url-status=live }} which lets users run queries on the data contained in Wikidata.{{cite web|url=https://lists.wikimedia.org/pipermail/wikidata/2015-September/007042.html|title=[Wikidata] Announcing the release of the Wikidata Query Service - Wikidata - lists.wikimedia.org|access-date=13 November 2018|archive-date=10 November 2015|archive-url=https://web.archive.org/web/20151110040230/https://lists.wikimedia.org/pipermail/wikidata/2015-September/007042.html|url-status=live}} The service uses SPARQL as the query language. As of November 2018, there are at least 26 different tools that allow querying the data in different ways.{{cite web|url=https://www.wikidata.org/wiki/Wikidata:Tools/Query_data|title=Wikidata:Tools/Query data – Wikidata|website=www.wikidata.org|access-date=13 November 2018|archive-date=31 May 2020|archive-url=https://web.archive.org/web/20200531044004/https://www.wikidata.org/wiki/Wikidata:Tools/Query_data|url-status=live}} It uses Blazegraph as its triplestore and graph database.{{cite web|url=https://lists.wikimedia.org/pipermail/wikidata-tech/2015-March/000740.html|title={{Square bracket open}}Wikidata-tech{{Square bracket close}} Wikidata Query Backend Update (take two!)|language=en|website=lists.wikimedia.org|accessdate=2018-08-29|archive-date=6 January 2021|archive-url=https://web.archive.org/web/20210106191817/https://lists.wikimedia.org/pipermail/wikidata-tech/2015-March/000740.html|url-status=live}} (The message also contains a link to the graph databases comparison performed by Wikimedia.){{GitHub |blazegraph/database/issues/86}}

In 2021, Wikimedia Deutschland released the Query Builder,{{Cite web|url=https://query.wikidata.org/querybuilder/|title=Wikidata Query Builder|website=query.wikidata.org}} "a form-based query builder to allow people who don't know how to use SPARQL" to write a query.

The bars on the logo contain the word "WIKI" encoded in Morse code.commons:File talk:Wikidata-logo-en.svg#Hybrid. Retrieved 2016-10-06. It was created by Arun Ganesh and selected through community decision.{{cite web|url=https://blog.wikimedia.de/2012/07/13/und-der-gewinner-ist/|title=Und der Gewinner ist...|date=13 July 2012|access-date=16 June 2020|archive-date=21 January 2021|archive-url=https://web.archive.org/web/20210121061656/https://blog.wikimedia.de/2012/07/13/und-der-gewinner-ist/|url-status=live}}

In November 2014, Wikidata received the Open Data Publisher Award from the Open Data Institute "for sheer scale, and built-in openness".{{cite web|url=http://theodi.org/news/first-odi-open-data-awards-presented-by-sir-tim-berners-lee-and-sir-nigel-shadbolt|archive-url=https://web.archive.org/web/20160324003214/http://theodi.org/news/first-odi-open-data-awards-presented-by-sir-tim-berners-lee-and-sir-nigel-shadbolt|archive-date=2016-03-24|title=First ODI Open Data Awards presented by Sirs Tim Berners-Lee and Nigel Shadbolt|work=Open Data Institute }}

In December 2014, Google announced that it would shut down Freebase in favor of Wikidata.{{cite web|url = https://plus.google.com/109936836907132434202/posts/bu3z2wVqcQc|title = Freebase|date = 16 December 2014|archive-url = https://web.archive.org/web/20190320195748/https://plus.google.com/109936836907132434202/posts/bu3z2wVqcQc|archive-date = 20 March 2019|website = Google Plus}}

{{As of|2018|November}}, Wikidata information was used in 58.4% of all English Wikipedia articles, mostly for external identifiers or coordinate locations. In aggregate, data from Wikidata is shown in 64% of all Wikipedias' pages, 93% of all Wikivoyage articles, 34% of all Wikiquotes', 32% of all Wikisources', and 27% of Wikimedia Commons.{{cite web|url=http://wdcm.wmflabs.org/WD_percentUsageDashboard/|title=Percentage of articles making use of data from Wikidata|access-date=15 November 2018|archive-date=15 November 2018|archive-url=https://web.archive.org/web/20181115114237/http://wdcm.wmflabs.org/WD_percentUsageDashboard/|url-status=dead}}

{{As of|2020|December}}, Wikidata's data was visualized by at least 20 other external tools{{cite web|url=https://www.wikidata.org/wiki/Wikidata:Tools/Visualize_data|title=Wikidata:Tools/Visualize data – Wikidata|website=www.wikidata.org|access-date=15 November 2018|archive-date=15 November 2018|archive-url=https://web.archive.org/web/20181115112950/https://www.wikidata.org/wiki/Wikidata:Tools/Visualize_data|url-status=live}} and over 300 papers have been published about Wikidata.{{cite web|url=https://scholia.toolforge.org/topic/Q2013|title=Scholia|website=Scholia|access-date=2 August 2021|archive-date=30 September 2021|archive-url=https://web.archive.org/web/20210930185838/https://scholia.toolforge.org/topic/Q2013|url-status=live}}

• Wikidata's structured dataset has been used by virtual assistants such as Apple's Siri and Amazon Alexa.{{Cite magazine |last1=Simonite |first1=Tom |date=2019-02-18 |title=Inside the Alexa-Friendly World of Wikidata |url=https://www.wired.com/story/inside-the-alexa-friendly-world-of-wikidata/ |access-date=2020-12-25 |magazine=Wired |language=en-us |issn=1059-1028}}{{Cite web |last1=Merhav |first1=Yuval |last2=Ash |first2=Steve |date=2018-08-08 |title=Automatic transliteration can help Alexa find data across language barriers |url=https://www.amazon.science/blog/automatic-transliteration-can-help-alexa-find-data-across-language-barriers |access-date=2025-02-03 |website=Amazon Science |language=en}}
• Mwnci extension can import data from Wikidata to LibreOffice Calc spreadsheets{{cite web|url=https://gitlab.com/muishkin/mwnci---deep-spreadsheets|title=Rob Barry / Mwnci – Deep Spreadsheets|website=GitLab|access-date=21 September 2019|archive-date=21 September 2019|archive-url=https://web.archive.org/web/20190921132219/https://gitlab.com/muishkin/mwnci---deep-spreadsheets/|url-status=live}}
• KDE Itinerary – a privacy conscious open source travel assistant that uses data from Wikidata{{Citation|last=Krause|first=Volker|title=KDE Itinerary – A privacy by design travel assistant|date=12 January 2020|url=https://media.ccc.de/v/36c3-59-kde-itinerary-a-privacy-by-design-travel-assistant#t=33|language=en|access-date=2020-11-10|archive-date=26 June 2020|archive-url=https://web.archive.org/web/20200626012643/https://media.ccc.de/v/36c3-59-kde-itinerary-a-privacy-by-design-travel-assistant#t=33|url-status=live}}
• Google originally started a frame semantic parser project that aims to parse the information on Wikipedia and transfer it into Wikidata by coming up with relevant statements using artificial intelligence.{{GitHub |google/sling}}
• MathQA – a mathematical question answering systemScharpf, P. Schubotz, M. Gipp, B. [https://www.gipp.com/wp-content/papercite-data/pdf/scharpf2022.pdf Mining Mathematical Documents for Question Answering via Unsupervised Formula Labeling] {{Webarchive|url=https://web.archive.org/web/20230210114012/https://www.gipp.com/wp-content/papercite-data/pdf/scharpf2022.pdf |date=10 February 2023 }} ACM/IEEE Joint Conference on Digital Libraries, 2022.

A systematic literature review of the uses of Wikidata in research was carried out in 2019.{{cite journal |last1=Mora-Cantallops |first1=Marçal |last2=Sánchez-Alonso |first2=Salvador |last3=García-Barriocanal |first3=Elena |title=A systematic literature review on Wikidata |journal=Data Technologies and Applications |date=2 September 2019 |volume=53 |issue=3 |pages=250–268 |doi=10.1108/DTA-12-2018-0110|s2cid=202036639 }}

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• {{citation |url=https://www.theatlantic.com/technology/archive/2012/04/the-problem-with-wikidata/255564/ |work=The Atlantic |location=US |date= 6 April 2012 |title=The Problem With Wikidata |author=Mark Graham }}
• Claudia Müller-Birn, Benjamin Karran, Janette Lehmann, Markus Luczak-Rösch: [http://eprints.soton.ac.uk/377397/1/paper-1.pdf Peer-production system or collaborative ontology development effort: What is Wikidata?] In, OpenSym 2015 – Conference on Open Collaboration, San Francisco, US, 19 – 21 Aug 2015 (preprint).

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