Parallel universes

this can mean many things, i'll go over them

in physics
in physics a parallel universe is a theory that their are many realities, similar yet different from our own, as our planet is in a universe so to are the realities in a multiverse

on parallel dimensions
while used interchangeably with one another, dimensions refer to how many different directions their are, (i.e. 1-D, 2-D and 3-D) so while a parallel reality may also be a parallel dimension, it is not inherently

in vidia
in video games, one can only program numbers in a certain range (usually 255 to -255) if it goes over or under the top or bottom end of that range, it loops back around to the other end

in some games, this causes the terrain to replicate it'self, and this is called a parallel universe, simple

could you imagine being the idiot that couldn't understand that?