English: Structure of an example Wikidata item. Wikidata items are linked to one another and to outside databases via properties which describe the relationships between them. A) Some example links to and from the item human retinoic acid receptor alpha (Q254943). Items can have outgoing links; e.g. to the concept of a protein (Q8054), incoming links; e.g. from the human RAR-SRC1 complex (Q107514806), or both; e.g. to and from the human RARA gene (Q18031040). There can be multiple links out with the same property (e.g. multiple molecular functions) and links out to external websites and identifiers; e.g. it has the MeSH ID (P486) of D011506. The links formed by properties can be further annotated with qualifiers; e.g. its physical interaction with (P129) tretinoin (Q29417) is with the role of (P2868) being an agonist (Q389934). Now imagine this for a hundred million node items and many billions of property edges. B) The human-readable interface for this item is organised into the label, description and aliases, followed by a list of statements with their qualifications and references, with a final section listing any Wikipedia (and other wikimedia) pages for the item. C) Example labels, descriptions and aliases for virus (Q808) from the 410 currently supported languages.