There is a hierarchy of config files that corresponds to the hierarchy of world definitions.
Sponge makes a distinction between a “dimension” and a "world"
A dimension is a type of world (e.g. overworld, nether) whereas a world is a particular instance of that dimension.
In vanilla, you have one world per dimension i.e:
However you may want to have multiple worlds of the same dimension, or have a plugin/mod that adds a new dimension.
dimension.conf controls the configuration for that dimension, whereas a
world.conf controls the config for that particular world instance.
Note that configs only take effect when
true, by default they are
false, meaning the default config is used (