A MOO is an on-line environment where people come to exist, as themselves, or to play any role they want.
MOOs are in use more and more on the virtual campus.
A MOO can be a useful feature for instructors wanting to experiment with a class discussion that did not have a visible authority figure in it. Still in the development stages, it is already functioning as a classroom for students of language in several Institutions. Some of its uses are, for holding virtual office hours, student-teacher conferences, seminars on writing, and small group projects. Harper's Tale is an online role-playing game, a simulation of the world of Pern. MUSEs support real-time interaction among many participants who collaborate to build their own world.