Parallel-Worlds
Parallel-Worlds
Parallel worlds exist in parallel, alternate universes where, although there are a great many similarities to our known universe, as in the case of Earth-1 with our Superman and the Superman of Earth-2.
This profound cosmological discovery was first made on Earth by The Flash when he inadvertently crossed over to Earth 2 and met his childhood comic book hero, Flash of Earth-2 (The Flash No. 123, Sep 1961: "Flash of Two Worlds!").
Often the Justice League of America would team with their dimensional counterparts, the Justice Society of Earth-2, in battling other evil dimensional variations.
Superboy once faced marauding intruders from not only the future 30th Century but a parallel world as well.
Some of the parallel-words are:
- Earth-1
 - Earth-2
 - Earth-3
 - Earth-E
 - Earth-Prime
 - Earth-S
 - Earth-T
 - Earth-X (Freedom Fighters)
 - Earth-X (Steelman)
 
