A World is a prominent item in the Disney multiverse.
The Disney Multiverse contains a huge (actualy nearly infinite) amount of Worlds. They are divided in Natural worlds and Magically-created worlds.
These Worlds are copies of our universes, with a little twist somewhere. Most of the twists are about these worlds's version of planet Earth, as in many cases, countries and persons that don't exist in our world exist there. Also, sometimes, the universes are a few years younger than ours, so the Earth looks medieval or even ancient. Most Disney movies and TV shows are set in these worlds, with each movie having its own. In cases where there is a crossover, interestingly, the two movies and their crossover produce 3 different worlds: a world for each movie in which the setting of each other doesn't exist, and the world in which the crossover takes place, that is one where the two movies happened. The crossover worlds are called Shared Worlds.
Magically created worldsEdit
These are worlds that are of limited size and are not quite like our world at all. Heaven can be considered a good example of that, just like the Other Side.