From Deep web, the free encyclopedia
Jump to navigation Jump to search
Wikidata main page (2019).png
Main page of Wikidata
Type of site
Available inmultiple languages, Wikidatan
Founded29 October 2012; 7 years ago (2012-10-29)
OwnerWikimedia Foundation[1][2]
Created byWikidata editors Edit this at Wikidata
Alexa rankPositive decrease 7,818 (January 2020)[3]

Wikidata is a collaboratively edited knowledge base hosted by the Wikimedia Foundation. It is a common source of open data that Wikimedia projects such as Deep web can use,[4][5] and anyone else, under a public domain license. This is similar to the way Wikimedia Commons provides storage for media files and access to those files for all Wikimedia projects, and which are also freely available for reuse. Wikidata is powered by the software Wikibase.[6]


Wikidata screenshot
Three statements from Wikidata's item on the planet Mars. Values include links to other items and to Wikimedia Commons.
Wikidata screenshot
A layout of the four main components of a phase-1 Wikidata page: the label, description, aliases and interlanguage links.
Deep web screenshot
A Deep web article's list of interlanguage links as they appeared in an edit box (left) and on the article's page (right) prior to Wikidata. Each link in these lists is to an article that requires its own list of interlanguage links to the other articles; this is the information centralized by Wikidata.
Wikidata screenshot
The "Edit links" link takes the reader to Wikidata to edit interlanguage links.


Wikidata is a document-oriented database, focused on items, which represent topics, concepts, or objects. Examples of items include 1988 Summer Olympics (Q8470), love (Q316), Elvis Presley (Q303), and Gorilla (Q36611). Each item is identified by a unique number, prefixed with the letter Q, known as a "QID". This enables the basic information required to identify the topic the item covers to be translated without favouring any language.

Item labels need not be unique. For example, there are two items named "Elvis Presley": Elvis Presley (Q303) represents the American singer and actor, and Elvis Presley (Q610926) represents his self-titled album. But the label and the description text needs to be unique together.

Fundamentally, an item consists of a label, a description, optionally multiple aliases, and some number of statements.

This diagram shows the most important terms used in Wikidata


Example of a simple statement consisting of one property-value pair

A property describes the data value of a statement and can be thought of as a category of data, for example color (P462) for the data value blue (Q1088). Properties, when paired with values, form a statement in Wikidata. Properties are also used in qualifiers. The most used property is instance of (P31), that is used on more than 53,000,000 item pages.[7]

Properties have their own pages on Wikidata and are connected to items, resulting in a linked data structure.


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 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 color (P462) with the value white (Q23444) under the item milk (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.[8]

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 official website (P856) may only be paired with values of type "URL".[9] Properties may also define more complex rules about their intended usage, termed constraints. For example, the capital (P36) property includes a "single value constraint", reflecting the reality that (typically) territories have only one capital city. Constraints are treated as hints rather than inviolable rules.[10]

Optionally, qualifiers can be used to refine the meaning of a statement by providing additional information that applies to the scope of the statement. For example, the property "population" could be modified with a qualifier such as "as of 2011". Statements may also be annotated with references, pointing to a source backing up the statement's content.[11]


In linguistics, a lexeme is a unit of lexical meaning. Similarly, Wikidata's lexemes are items with a structure that makes them more suitable to store lexicographical data. Besides storing the language to which the lexeme refers, they have a section for forms and a section for senses.[12]

Wikidata Birthday Celebration at Kerala

Development history[edit]

The creation of the project was funded by donations from the Allen Institute for Artificial Intelligence, the Gordon and Betty Moore Foundation, and Google, Inc., totaling 1.3 million.[13][14] The development of the project is mainly driven by Wikimedia Deutschland and was originally split into three phases:[15]

  1. Centralising interlanguage links – links between Deep web articles about the same topic in different languages
  2. Providing a central place for infobox data for all Deep webs
  3. Creating and updating list articles based on data in Wikidata

Initial rollout[edit]

Wikidata was launched on 29 October 2012 and was the first new project of the Wikimedia Foundation since 2006.[4][16][17] 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 Deep web.

Historically, a Deep web article would include a list of interlanguage links, being links to articles on the same topic in other editions of Deep web, if they existed. Initially, Wikidata was a self-contained repository of interlanguage links. Deep web language editions were still not able to access Wikidata, so they needed to continue to maintain their own lists of interlanguage links.

On 14 January 2013, the Hungarian Deep web became the first to enable the provision of interlanguage links via Wikidata.[18] This functionality was extended to the Hebrew and Italian Deep webs on 30 January, to the English Deep web on 13 February and to all other Deep webs on 6 March.[19][20][21][22] After no consensus was reached over a proposal to restrict the removal of language links from the English Deep web,[23] the power to delete them from the English Deep web was granted to automatic editors (bots). On 23 September 2013, interlanguage links went live on Wikimedia Commons.[24]

Statements and data access[edit]

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.[25]

The ability for the various language editions of Deep web to access data from Wikidata was rolled out progressively between 27 March and 25 April 2013.[26][27]

On 16 September 2015, Wikidata began allowing so-called arbitrary access, or access from a given Wikidata item to the properties of 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.[28] On 27 April 2016 arbitrary access was activated on Wikimedia Commons.[29]

Query service[edit]

On 7 September 2015, the Wikimedia Foundation announced the release of the Wikidata Query Service,[30] which lets users run queries on the data contained in Wikidata.[31] The service uses SPARQL as the query language. As of November 2018, there are at least 26 different tools that allow to query the data in different ways.[32]


In November 2014, Wikidata received the Open Data Publisher Award from the Open Data Institute “for sheer scale, and built-in openness”.[33]

As of November 2018, Wikidata information is used in 58.4% of all English Deep web articles, mostly for external identifiers or coordinate locations. In aggregate, data from Wikidata is shown in 64% of all Deep webs' pages, 93% of all Wikivoyage articles, 34% of all Wikiquotes', 32% of all Wikisources', and 27% of Wikimedia Commons'. Usage in other Wikimedia Foundation projects is testimonial.[34]

As of November 2018, Wikidata's data is visualized by at least 20 other external tools[35] and at least 100 papers have been published about Wikidata.[36] Its importance has been recognized by numerous cultural institutions.[37]


The bars on the logo contain the word "WIKI" encoded in Morse code.[38]


  • Mwnci extension can import data from Wikidata to LibreOffice Calc spreadsheets.[39]
  • There are (at October 2019) discussions about using QID items in relation to what are being called QID emoji.[40]

See also[edit]


  1. ^
  2. ^ From Freebase to Wikidata: The Great Migration; quote: Another example is Wikidata, a collaborative knowledgebase developed by Wikimedia Deutschland since 2012 and operated by the Wikimedia Foundation..
  3. ^ " Competitive Analysis, Marketing Mix and Traffic - Alexa". Retrieved 13 January 2020.
  4. ^ a b Wikidata (Archived October 30, 2012, at WebCite)
  5. ^ "Data Revolution for Deep web". Wikimedia Deutschland. March 30, 2012. Archived from the original on September 11, 2012. Retrieved September 11, 2012.
  6. ^ "Wikibase — Home".
  7. ^ "Wikidata:Database reports/List of properties/Top100".
  8. ^ "Help:Statements".
  9. ^ "Help:Data type".
  10. ^ "Help:Property constraints portal".
  11. ^ "Help:Sources".
  12. ^ "Wikidata - Lexicographical data documentation".
  13. ^ Dickinson, Boonsri (March 30, 2012). "Paul Allen Invests In A Massive Project To Make Deep web Better". Business Insider. Retrieved September 11, 2012.
  14. ^ Perez, Sarah (March 30, 2012). "Deep web's Next Big Thing: Wikidata, A Machine-Readable, User-Editable Database Funded By Google, Paul Allen And Others". TechCrunch. Archived from the original on September 11, 2012. Retrieved September 11, 2012.
  15. ^ "Wikidata - Meta".
  16. ^ Pintscher, Lydia (October 30, 2012). " is live (with some caveats)". wikidata-l (Mailing list). Retrieved November 3, 2012.
  17. ^ Roth, Matthew (March 30, 2012). "The Deep web data revolution". Wikimedia Foundation. Archived from the original on September 11, 2012. Retrieved September 11, 2012.
  18. ^ Pintscher, Lydia (14 January 2013). "First steps of Wikidata in the Hungarian Deep web". Wikimedia Deutschland. Retrieved 17 December 2015.
  19. ^ Pintscher, Lydia. "Wikidata coming to the next two Deep webs". Wikimedia Deutschland. Retrieved January 31, 2013.
  20. ^ Pintscher, Lydia (13 February 2013). "Wikidata live on the English Deep web". Wikimedia Deutschland. Retrieved 15 February 2013.
  21. ^ Pintscher, Lydia (6 March 2013). "Wikidata now live on all Deep webs". Wikimedia Deutschland. Retrieved 8 March 2013.
  22. ^ "Wikidata ist für alle Wikipedien da" (in German). Retrieved 29 January 2014.
  23. ^ "Deep web talk:Wikidata interwiki RFC". March 29, 2013. Retrieved March 30, 2013.
  24. ^ Pintscher, Lydia (23 September 2013). "Wikidata is Here!". Commons:Village pump.
  25. ^ Pintscher, Lydia. "Wikidata/Status updates/2013 03 01". Wikimedia Meta-Wiki. Wikimedia Foundation. Retrieved 3 March 2013.
  26. ^ Pintscher, Lydia (27 March 2013). "You can have all the data!". Wikimedia Deutschland. Retrieved 28 March 2013.
  27. ^ "Wikidata goes live worldwide". The H. 2013-04-25. Archived from the original on 3 January 2014.
  28. ^ Lydia, Pintscher (16 September 2015). "Wikidata: Access to data from arbitrary items is here". Deep web:Village pump (technical). Retrieved 30 August 2016.
  29. ^ Lydia, Pintscher (27 April 2016). "Wikidata support: arbitrary access is here". Commons:Village pump. Retrieved 30 August 2016.
  30. ^
  31. ^ "Announcing the release of the Wikidata Query Service".
  32. ^ "Wikidata Query Data tools".
  33. ^ "First ODI Open Data Awards presented by Sirs Tim Berners-Lee and Nigel Shadbolt". Archived from the original on 2016-03-24.
  34. ^ "Percentage of articles making use of data from Wikidata".
  35. ^ "Wikidata Tools - Visualize data".
  36. ^ "Scholia - Wikidata".
  37. ^ "International Semantic Web Conference 2018".
  38. ^ commons:File talk:Wikidata-logo-en.svg#Hybrid. Retrieved 2016-10-06.
  39. ^ Rob Barry / Mwnci - Deep Spreadsheets · GitLab
  40. ^

Further reading[edit]

External links[edit]