The difference is simple:
Play
starts the execution of aSoundEffect
from the beginning of the audio fileResume
is the dual ofPause
, and let you resume aSoundEffect
from the moment you calledPause
UPDATE
If you're using SoundEffectInstance
here's the answer to your question.
Play method plays or resumes a SoundEffectInstance
So the difference is that you can do both things only using Play
, Resume
of course can't be called if the sound effect is not paused.