I'd say its a document database with direct links between documents, which can be quickly and easily traversed like a graph database. The graph API that Orient

I'd say its a document database with direct links between documents, which can be quickly and easily traversed like a graph database. The graph API that OrientDB exposes (the TinkerPop api, basically) seems to be built almost as a convention of which links should exist, on top of the document database. OrientDB is very flexible and powerful because of this: representing your data as linked documents feels really natural. I've been using RethinkDB lately, and I love it, but having used OrientDB previously, I find the lack of direct links between documents makes for complex and awkward nested queries. I'll continue to happily use RethinkDB, but I'm also eagerly watching OrientDB's progress and expect I'll be using it some more soon.