Wikidata is a free linked database that can be read and edited by both humans and machines.
Wikidata acts as central storage for the structured data of its Wikimedia sister projects including Wikipedia, Wikivoyage, Wikisource, and others.
Wikidata also provides support to many other sites and services beyond just Wikimedia projects! The content of Wikidata is available under a free license, exported using standard formats, and can be interlinked to other open data sets on the linked data web.
The answer: a lot of rich data in need of structure and new properties. But thanks to growing user contributions and the work of a new WikiProject, Wikidata is getting better at supporting name-related data—and can tell you that Juliet also goes by Julika, and Giulia, and Hülya, and Liana, and Uljana...
Check out Wikidata:Tools for some of our best tools and gadgets for using and exploring Wikidata.