In the interface 200, a new document 202 is displayed. The user has begun typing into the document, causing the user's input to appear in the document as text at the location of the cursor 204. In response to this typing, a system that created the interface 200 (e.g., the document system 108) can identify one or more factual entities that is described or referenced by the content of the document. In this case, the factual entity identified is a bear, which is described in the document. In another example, the same paragraph may be used to identify a yearly hibernation cycle factual entity. In general, a factual entity includes a single conceptual entity, such as a person, place, country, landmark, animal, historical event, organization, business, sports team, sporting event, movie, song, album, game, work of art, or any other entity. In some implementations, a factual entity is a concept, subject, or topic.

To identify a factual entity, the document system 108 can include an entity and context identifier 109. The entity and context identifier 109 can process the content of the document, e.g., text and images contained by the document, as well as metadata about the documents, e.g., document title, creation data, or access control lists. Using appropriate textual, semantic and other information processing algorithms, can identify one or more main subjects or entity of the document and the context in which the subjects are mentioned. The entity and context identifier 109 then generates, for example, a query for the knowledge panel system 110.