Your internal world is a repository of your experiences in-game. It is a client-side server, similar to a test server, where the limits are your personal experiences and creativity. Here you can try out things in god-mode, alchemy-style. You create models of things you may wish to share with others, by creating a recipe for recreating them on the community server, either solo or cooperatively. This is your mental space, where everything can happen quickly and easily, and in complete privacy and security.