Economies in virtual worlds have a large number of distinguishing characteristics. This ontology attempts to describe them in terms of two of the important ones: an open closed axis, and an externalized internalized axis — and then place a number of worlds into this structure.Open vs. ClosedAn open economy is one in which creators other than the original world (or platform) can contribute back to the world’s ecosystem in some meaningful way. A closed economy is one in which the abilit...