At the level of the earth, we could speak about other countries, and we can see immediately that this concept tends to disappear so much the lifestyles tend to be standardized.
In the broad sense (which is the direction first), the other worlds are of any kind:
- physical worlds, represented by other civilizations in galaxies close or towards the infinite of the universe
- parallel worlds represented by the infinite paths which the future (thus our present) could take if one modified an element or an event
- immaterial, spiritual worlds which consist of all that one cannot touch (what does not want to say of course that they do not exist).