An emerging ontologyEdit
Unlike most databases, the way editors describe how items relate to each other is always changing. Wikidata has an emergent ontology because its community of editors is constantly adding new items and organizing them in relation to other items. Some concepts are well established and documented, while others could use more details. For example, lighthouses have a clear set of properties editors use to describe them on Wikidata. On the other hand, descriptions of the common parts of electrical grids are still in development.